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PURPOSE Consensus molecular subtypes (CMSs) were evaluated as prognostic and predictive biomarkers of patients with RAS wild-type metastatic colorectal cancer (mCRC) receiving fluorouracil and folinic acid (FU/FA) with or without panitumumab (Pmab) after Pmab + mFOLFOX6 induction within the randomized phase II PanaMa trial. METHODS CMSs were determined in the safety set (ie, patients that received induction) and full analysis set (FAS; ie, randomly assigned patients who received maintenance) and correlated with median progression-free survival (PFS) and overall survival (OS) since the start of induction or maintenance treatment and objective response rates (ORRs). Hazard ratios (HRs) and 95% CI were calculated by univariate/multivariate Cox regression analyses. RESULTS Of 377 patients of the safety set, 296 (78.5%) had available CMS data: CMS1/2/3/4: 29 (9.8%)/122 (41.2%)/33 (11.2%)/112 (37.8%) and unclassifiable: 17 (5.7%). The CMSs were prognostic biomarkers in terms of PFS ( P < .0001), OS ( P < .0001), and ORR ( P = .02) since the start of induction treatment. In FAS patients (n = 196), with CMS2/4 tumors, the addition of Pmab to FU/FA maintenance therapy was associated with longer PFS (CMS2: HR, 0.58 [95% CI, 0.36 to 0.95], P = .03; CMS4: HR, 0.63 [95% CI, 0.38 to 1.03], P = .07) and OS (CMS2: HR, 0.88 [95% CI, 0.52 to 1.52], P = .66; CMS4: HR, 0.54 [95% CI, 0.30 to 0.96], P = .04). The CMS interacted significantly with treatment in terms of PFS (CMS2 v CMS1/3: P = .02; CMS4 v CMS1/3: P = .03) and OS (CMS2 v CMS1/3: P = .03; CMS4 v CMS1/3: P < .001). CONCLUSION The CMS had a prognostic impact on PFS, OS, and ORR in RAS wild-type mCRC. In PanaMa, Pmab + FU/FA maintenance was associated with beneficial outcomes in CMS2/4, whereas no benefit was observed in CMS1/3 tumors.

Purpose: To evaluate progression-free survival (PFS) as a potential surrogate endpoint (SEP) for overall survival (OS) in metastatic colorectal cancer (mCRC) with a focus on applicability to trials containing targeted therapy with anti-VEGF- or anti-EGF receptor (EGFR)–directed monoclonal antibodies.Experimental Design: A systematic literature search of randomized trials of first-line chemotherapy for mCRC reported from January 2000 to January 2012 was conducted. Adjusted weighted linear regression was used to calculate correlations within PFS and OS (endpoints; REP) and between treatment effects on PFS and on OS (treatment effects; RTE).Results: Fifty trials reflecting 22,736 patients met the inclusion criteria. Correlation between treatment effects on PFS and OS and between the endpoints PFS and OS was high across all studies (RTE = 0.87, REP = 0.86). This was also observed in chemotherapy-only trials (RTE = 0.93, REP = 0.81) but less so for trials containing monoclonal antibodies (RTE = 0.47; REP = 0.52). Limiting the analysis to bevacizumab-based studies (11 trials, 3,310 patients) again yielded high correlations between treatment effects on PFS and on OS (RTE = 0.84), whereas correlation within PFS and OS was low (REP = 0.45). In 7 trials (1,335 patients) investigating cetuximab- or panitumumab-based studies, contrasting correlations with very wide confidence intervals were observed (RTE = 0.28; REP = 0.96).Conclusions: PFS showed consistently high correlation with OS of an order that would justify its use as an SEP in chemotherapy regimens. For validation of surrogacy in anti-VEGF and anti-EGFR–directed therapies, further research and a larger set of trials is needed. Clin Cancer Res; 19(1); 225–35. ©2012 AACR.

PDF file - 82k, Trials included in the analysis

(1) Background: Sinusoidal obstruction syndrome (SOS) after oxaliplatin-based chemotherapy is associated with unfavorable outcomes after partial hepatectomy for colorectal liver metastases (CLM). Bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF), may prevent SOS development. We investigated the impact of VEGF-inhibition on the development of SOS in a murine model. (2) Methods: Male wild-type and CD39-null mice received oxaliplatin, additional anti-VEGF (OxAV), or controls, and were sacrificed or subjected to major partial hepatectomy (MH). Specimen were used for histological analysis of SOS. Liver damage was assessed by plasma transaminases. The VEGF pathway was elucidated by quantitative PCR of liver tissue and protein analysis of plasma. (3) Results: Mice treated with oxaliplatin developed SOS. Concomitant anti-VEGF facilitated a reduced incidence of SOS, but not in CD39-null mice. SOS was associated with increased plasma VEGF-A and decreased hepatocyte growth factor (HGF). After OxAV treatment, VEGF-R2 was upregulated in wild-type but downregulated in CD39-null mice. Oxaliplatin alone was associated with higher liver damage after MH than in mice with concomitant VEGF-inhibition. (4) Conclusions: We established a murine model of oxaliplatin-induced SOS and provided novel evidence on the protective effect of VEGF-inhibition against the development of SOS that may be associated with changes in the pathway of VEGF and its receptor VEGF-R2.

Background The XELAVIRI trial compared sequential (fluoropyrimidine and bevacizumab; irinotecan (Iri) at progression) versus initial combination therapy (fluoropyrimidine, bevacizumab, Iri) of treatment-naive metastatic colorectal cancer (mCRC). In the confirmatory analysis, the primary end-point (non-inferiority of sequential therapy regarding time to failure of strategy, TFS) was not met. Nevertheless, significant differences regarding treatment efficacy were observed according to RAS status. Here, we evaluate the consensus molecular subtypes (CMS) as additional biomarkers for sequential versus combination therapy. Material and methods Gene expression was measured using NanoString after mRNA extraction from formalin-fixed paraffin-embedded tumour specimens. CMS were predicted using multinomial regression and correlated with updated data for TFS, overall (OS) and progression-free survival. Results CMS were predicted in 337 of 421 (80.0%) patients (CMS1: 18.4%; CMS2: 51.6%; CMS3: 2.7%; CMS4: 27.3%). CMS2 together with RAS/BRAF wild-type status was identified as potential predictive marker of benefit from initial combination therapy for OS (HR 0.56, 95% CI 0.33–0.96, p = 0.036) and progression-free survival (HR 0.28, 95% CI 0.29–0.79, p = 0.004) and also trending in TFS (HR 0.63, 90% CI 0.41–0.95, p = 0.066). In patients with RAS-mutated mCRC, CMS1 was associated with longer OS after initial combination therapy (HR 0.43, 95% CI 0.20–0.95, p = 0.038). Interaction testing (two-sided) of CMS and RAS/BRAF status in favour of the combination treatment strategy was significant for OS (p = 0.012) Conclusions In patients with RAS/BRAF wild-type mCRC, CMS2 may serve as an additional biomarker of benefit from the initial combination therapy, including Iri. Trial registration Trial registration ID ( clinicaltrials.gov ) NCT01249638 .

Background and Objectives: After liver transplantation (LT), long-term immunosuppression (IS) is essential. IS is associated with de novo malignancies, and the incidence of colorectal cancer (CRC) is increased in LT patients. We assessed course of disease in patients with de novo CRC after LT with focus of IS and impact on survival in a retrospective, single-center study. Materials andMethods: All patients diagnosed with CRC after LT between 1988 and 2019 were included. The management of IS regimen following diagnosis and the oncological treatment approach were analyzed: Kaplan–Meier analysis as well as univariate and multivariate analysis were performed. Results: A total of 33 out of 2744 patients were diagnosed with CRC after LT. Two groups were identified: patients with restrictive IS management undergoing dose reduction (RIM group, n = 20) and those with unaltered regimen (maintenance group, n = 13). The groups did not differ in clinical and oncological characteristics. Statistically significant improved survival was found in Kaplan–Meier analysis for patients in the RIM group with 83.46 (8.4–193.1) months in RIM and 24.8 (0.5–298.9) months in the maintenance group (log rank = 0.02) and showed a trend in multivariate cox regression (p = 0.054, HR = 14.3, CI = 0.96–213.67). Conclusions: Immunosuppressive therapy should be reduced further in patients suffering from CRC after LT in an individualized manner to enable optimal oncological therapy and enable improved survival.

Secondary resection of metastases is recommended in metastatic colorectal cancer (mCRC). Data describing changes in mutational profiles of corresponding primary tumor and metastatic tissue after conversion treatment are limited. Next generation sequencing was performed in formalin-fixed mCRC samples from patients of the FIRE-3 trial (FOLFIRI plus cetuximab or bevacizumab) before treatment start (baseline) and after secondary resection of metastases (post baseline). Changes of mutational profiles and tumor mutational burden (TMB) were assessed within a post-hoc analysis. Median overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were compared between treatment arms. Paired tumor samples were obtained from 25 patients (19 RAS wild-type, 6 RAS mutant by pyrosequencing). ORR (92.0% vs 58.0%) and OS (60.8 vs 35.4 months, hazard ratio = 0.39 [95% CI 0.14-1.12], P = .08) were higher for patients receiving cetuximab. After conversion therapy, 56 alterations (42 in the cetuximab and 14 in the bevacizumab arm) were newly observed in 18 patients (9 each treated with cetuximab or bevacizumab). Gains (n = 21) and losses (n = 21) of alterations occurred during cetuximab-based treatment, while mainly gains of alterations occurred during bevacizumab (n = 10). Three of nine patients treated with cetuximab that presented a change of mutational profiles, developed resistance to cetuximab. Mutational profiles were largely comparable before and after treatment with anti-VEGF or anti-EGFR directed monoclonal antibodies after secondary resection. Mutations associated with resistance to anti-EGFR antibodies were observed in only one-third of patients.

CA extern Simple Summary The emergence of resistant cells remains a major obstacle for chemotherapy treatment of metastatic colorectal cancers. Improvement of the therapeutic response requires a thorough understanding of the mechanisms of resistance as well as informative biomarkers. In the REVEAL study, we have systematically compared the mutational patterns and expression profiles of primary tumor specimens before and after first-line chemotherapy treatment in the metastatic situation. In addition, we analyzed liquid biopsies pre, during, and after treatment. Alterations in gene expression appeared as the major drivers of chemotherapy resistance. We identified a gene expression signature differentiating primary tumors and metastases and validated this signature in two independent patient cohorts. Moreover, we evaluated the expression of two signature genes, SFRP2 and SPP1, as prognostic and potentially druggable biomarkers. Most metastatic colorectal cancer (mCRC) patients succumb to refractory disease due to secondary chemotherapy resistance. To elucidate the molecular changes associated with secondary resistance, we recruited 64 patients with mCRC and hepatic metastases before standard first-line chemotherapy between 2014 and 2018. We subjected DNA from primary tumor specimens (P), hepatic metastasis specimens after treatment (M), and liquid biopsies (L) taken prior to (pre), during (intra), and after (post) treatment to next generation sequencing. We performed Nanostring expression analysis in P and M specimens. Comparative bioinformatics and statistical analysis revealed typical mutational patterns with frequent alterations in TP53, APC, and KRAS in P specimens (n = 48). P and pre-L (n = 42), as well as matched P and M (n = 30), displayed a similar mutation spectrum. In contrast, gene expression profiles classified P (n = 31) and M (n = 23), distinguishable by up-regulation of immune/cytokine receptor and autophagy programs. Switching of consensus molecular subtypes from P to M occurred in 58.3% of cases. M signature genes SFRP2 and SPP1 associated with inferior survival, as validated in an independent cohort. Molecular changes during first-line treatment were detectable by expression profiling rather than by mutational tumor and liquid biopsy analyses. SFRP2 and SPP1 may serve as biomarkers and/or actionable targets.

Metastatic colorectal cancer (mCRC) is a heterogeneous disease with distinct molecular subtypes. The BRAFAnonymized data from BRAFForty-two patients were eligible for analysis (mean age 62.1 years, 47.6% female). At initial diagnosis, 20 patients (47.6%) were documented with right-sided tumors. Most patients (81.0%) were tested for BRAF before 1Combined chemotherapy+TT (anti-VEGF/VEGFR and anti-EGFR) played a predominant role in BRAF

Nach R0-Resektion eines Kolonkarzinoms im Stadium II und III gemas UICC (Union for International Cancer Control) soll die Indikation zur adjuvanten Therapie gepruft werden. Die Empfehlungen richten sich bislang nach klinischen und histopathologischen Kriterien. Im Stadium II soll die hochgradige Mikrosatelliteninstabilitat (MSI-H) bei der Therapieentscheidung einbezogen werden. Auserdem soll das Risiko fur eine erhohte Toxizitat, wie das Vorliegen von Begleiterkrankungen, eine eingeschrankte Dihydropyrimidindehydrogenase(DPD)-Funktion oder das Alter des Patienten beachtet werden. Immunonkologische Ansatze fur MSI-H-Tumoren oder molekular zielgerichtete Ansatze bei BRAF-mutierten Tumoren werden in lokalisierten Stadien perioperativ in Studien gepruft. Weitere molekulare Parameter, u. a. die zirkulierende Tumor-DNA (ctDNA), werden auf ihre prognostische und pradiktive Wertigkeit hin getestet. Die Gruppe der alteren Patienten wird perspektivisch das groste Kollektiv darstellen und sollte zunehmend beachtet werden.

Beim Kolonkarzinom handelt es sich um eines der haufigsten Malignome in Deutschland. Aufgrund des unterschiedlichen biologischen Verhaltens infolge der molekularen Heterogenitat der Kolonkarzinome ist die optimale Kombination und Sequenz der in der palliativen Behandlungssituation verfugbaren Systemtherapien Gegenstand der aktuellen wissenschaftlichen Diskussion. Die zur Behandlung des metastasierten Kolonkarzinoms verfugbaren Systemtherapien (Chemotherapie, monoklonale Antikorper, Immuntherapie) werden beschrieben, die optimale Kombination und Sequenz der Substanzen werden erortert. Relevante Studien und Expertenempfehlungen werden analysiert und aktuell in Rekrutierung befindliche Studien vorgestellt. In der Systemtherapie des metastasierten Kolonkarzinoms stehen unter Berucksichtigung der molekularen Tumorcharakterisierung (KRAS; NRAS; BRAF; Mikrosatelliteninstabilitat, MSI) monoklonale Antikorper, Immuncheckpointinhibitoren und klassische Chemotherapeutika zur Verfugung. Durch die Integration zielgerichteter Substanzen in die Behandlung des metastasierten Kolonkarzinoms kann das Uberleben der Patienten signifikant verlangert werden. Das Uberleben von Patienten mit metastasiertem Kolonkarzinom konnte in den vergangenen Jahren kontinuierlich verbessert werden. Die optimale Therapiekombination und -sequenz wird durch die molekularpathologische Tumorcharakterisierung und die in den nachfolgenden Therapielinien zur Verfugung stehenden Behandlungsoptionen bestimmt.

Durch die Etablierung multimodaler Konzepte wurde bei vielen gastrointestinalen Tumorentitaten eine Prognoseverbesserung erzielt. Allerdings bedarf es zur Realisierung interdisziplinarer Therapieansatze einer Minimierung moglicher Nebenwirkungen und Komplikationen. Ziel war die Zusammenfassung und Bewertung aktueller Entwicklungen zur Vermeidung therapieassoziierter Nebenwirkungen und Komplikationen. Der wissenschaftliche Stand wurde anhand vorliegender Literatur zusammengefasst und entsprechend eigenen Zentrumserfahrungen bewertet. Die Systemtherapie bei oligometastasierten gastrointestinalen Tumoren richtet sich auf verschiedene Ziele (Mikrometastasen, Verkleinerung der Lasionen, biologische Selektion), sodass die Toxizitat im Kontext der Zielsetzung betrachtet werden muss. Fur die meisten Konstellationen scheint eine Therapiedauer von 3(–6) Monaten suffizient. Die Hochprazisionsstrahlentherapie ermoglicht die effektive und schonende Behandlung von Metastasen im gesamten Korper. Durch diese nichtinvasive konsolidierende Lokaltherapie kann neben dem progressionsfreien Uberleben teilweise auch das Gesamtuberleben im Vergleich zur alleinigen Systemtherapie verbessert werden. Vorteile der laparoskopischen gegenuber der offenen Operationstechnik zeigen sich bei chirurgischen Eingriffen in verbesserten perioperativen Ergebnissen. Durch die Einbindung in perioperative ERAS-Programme („enhanced recovery after surgery“) konnen therapieassoziierte Komplikationen weiter minimiert werden. Die Minimierung von Nebenwirkungen und Komplikationen ist die Grundlage zur Realisierung interdisziplinarer Therapieansatze. Ein ganzheitliches Verstandnis und gute Kommunikation beteiligter Fachabteilungen ist unabdingbar fur ein erfolgreiches Management dieser hochkomplexen Falle.

Die qualitatsgesicherte, pratherapeutische Bildgebung des lokal fortgeschrittenen Rektumkarzinoms mittels Magnetresonanztomographie ermoglicht eine optimale Planung der perioperativen Therapie dieses Tumors. Im vorliegenden Beitrag werden Qualitatskriterien der Magnetresonanztomographie sowie deren potenzielle therapeutische Implikation sowie laufende Studien der Deutschen Rektumkarzinom-Studiengruppe von einem multidisziplinaren Autorenteam dargestellt.

Background Tumor assessments after first-line therapy of RAS wild-type mCRC with cetuximab (cet) versus bevacizumab (bev) in combination with FOLFIRI were evaluated for factors influencing resectability, conversion to resectability, and survival after best response. Methods Conversion to resectability was defined as conversion of initially unresectable to resectable disease at best response as determined by retrospective assessment. Univariate and multivariate logistic models were fitted with resectability at best response as response variable. A Cox model comparing the survival from best response was used to measure the influence of treatment, resectability at best response, and resection. Interaction of resection and treatment arm on survival was tested by likelihood ratio test. Results Overall, 270 patients were evaluable (127 cet-arm, 143 bev-arm). Lung metastases (odds ratio [OR] 0.35, 95% confidence response [CI] 0.19–0.63), BRAF mutation (OR 0.33, 95% CI 0.12–0.82), and elevated alkaline phosphatase (OR 0.42, 95% CI 0.18–0.9) before randomization were associated with less chance of successful conversion and were integrated into a nomogram. Early tumor shrinkage (OR 1.86, 95% CI 1.06–3.3; p 0.034) and depth of response (OR 1.02, 95% CI 1.01–1.03; p p = 0.039), predominantely in cet-treated patients (interaction test, p = 0.02). Conclusions Conversion to resectability is significantly associated with baseline characteristics that can be used in a nomogram to predict conversion. Moreover, early efficacy parameters (ETS and DpR) are associated with successful conversion therapy. In FIRE-3, resection of metastases was associated with improved post-best response survival, this effect originated predominantly from the cetuximab-based study arm.

ZusammenfassungZur Indikationsstellung und Stratifizierung der perioperativen Therapie des lokal fortgeschrittenen Rektumkarzinoms ist die Magnetresonanztomografie unverzichtbar. Im vorliegenden Beitrag werden der Stellenwert der MRT-Diagnostik und die qualitativen Voraussetzungen dargestellt.

Purpose In mCRC, disease dynamics may play a critical role in the understanding of long-term outcome. We evaluated depth of response (DpR), time to DpR, and post-DpR survival as relevant endpoints. Methods We analyzed DpR by central review of computer tomography images (change from baseline to smallest tumor diameter), early tumor shrinkage (≥ 20% reduction in tumor diameter at first reassessment), time to DpR (study randomization to DpR-image), post-DpR progression-free survival (pPFS = DpR-image to tumor progression or death), and post-DpR overall survival (pOS = DpR-image to death) with special focus on BRAF status in 66 patients and primary tumor site in 86 patients treated within the VOLFI-trial, respectively. Results BRAF wild-type (BRAF-WT) compared to BRAF mutant (BRAF-MT) patients had greater DpR (− 57.6% vs. − 40.8%, p = 0.013) with a comparable time to DpR [4.0 (95% CI 3.1–4.4) vs. 3.9 (95% CI 2.5–5.5) months; p = 0.8852]. pPFS was 6.5 (95% CI 4.9–8.0) versus 2.6 (95% CI 1.2–4.0) months in favor of BRAF-WT patients (HR 0.24 (95% CI 0.11–0.53); p p Conclusions BRAF-MT patients derive a less profound treatment response compared to BRAF-WT patients. The difference in outcome according to BRAF status is evident after achievement of DpR with BRAF-MT patients hardly deriving any further disease control beyond DpR. Our observations hint towards an aggressive tumor evolution in BRAF-MT tumors, which may already be molecularly detectable at the time of DpR.

Lebermetastasen stellen die haufigste sekundar maligne Erkrankung der Leber dar. Zahlen zur Inzidenz kolorektaler und nichtkolorektaler Lebermetastasen lassen sich aufgrund mangelnder Erfassung in Registern nur unzureichend untersuchen. Daten zur neoadjuvanten Therapie sind begrenzt und meist retrospektiv analysiert. Zusammenfassung und Bewertung der Sinnhaftigkeit neoadjuvanter Therapiekonzepte fur kolorektale und nichtkolorektale Lebermetastasen. Die Analyse erfolgte auf Grundlage der europaischen und US-amerikanischen Leitlinien und umfasste deutsche und englischsprachige Publikationen. Ergebnisse und Empfehlungen werden zusammengefasst und es wird ein Uberblick uber die Literatur gegeben. Die neoadjuvante Therapie von Lebermetastasen erfolgt in heterogener Intention, sowohl die Selektion biologisch gunstiger Tumoren als auch die Konversion eines inoperablen Befundes in einen resektablen Befund sind klassische Beweggrunde fur eine neoadjuvante Therapie. Die Sinnhaftigkeit neoadjuvanter Therapiekonzepte fur kolorektale und insbesondere nichtkolorektale Lebermetastasen ist dem aktuellen Stand der Literatur und Leitlinien folgend nicht durchgehend schlussig zu beantworten. Die Erstellung der Therapiestrategie in der klinischen Praxis folgt in der Regel folgenden Kriterien: Metastasierungsmuster, Komplexitat der Resektion und biologische Faktoren (metachrone/synchrone Metastasen, Prognosefaktoren). Beim metastasierten kolorektalen Karzinom ist die Neoadjuvans im Kontext einer Konversionstherapie Standard. Biologische Selektion gunstiger Tumoren als Basis der Neoadjuvans bei resektablen Lasionen ist beim kolorektalen Karzinom kein durchgehender Standard. Nichtkolorektale Lebermetastasen werden nur im Rahmen individueller Konzepte reseziert.

Biliary tract cancer (BTC), including intra- and extrahepatic cholangiocarcinoma and gallbladder cancer, is a rare and highly difficult to manage human malignancy. Besides late diagnosis and associated unresectability, frequently observed unresponsiveness toward and recurrence following chemotherapy or targeted therapy essentially contribute to the dismal prognosis of BTC patients.The review provides an update on individual mechanisms involved resistance of BTC toward conventional chemotherapy as well as targeted therapies. We review the distinct mechanisms of pharmacoresistance (MPRs) which have been defined in BTC cells on a molecular basis and examine the specific consequences for the various approaches of chemo-, targeted or immunomodulatory therapies.Based on currently available experimental and clinical data, the present knowledge about these MPRs in BTCs are summarized. While some possible tactics for overcoming these mechanisms of resistance have been investigated, a BTC-specific and efficient approach based on comprehensive

BACKGROUND/AIM Metastatic colorectal cancer (mCRC) is a heterogeneous disease with distinct molecular subtypes. The BRAFV600E-mutation found in approximately 8-12% of mCRC patients is associated with poor prognosis. Guideline recommendations for this population are mostly based on small cohorts due to lack of clinical data. This retrospective analysis was designed to evaluate (approved) therapeutic approaches and algorithms in BRAFV600E-mutant mCRC prior to approval of the targeted combination encorafenib plus cetuximab in Germany, Austria, and Switzerland. PATIENTS AND METHODS Anonymized data from BRAFV600E-mutant mCRC patients were analyzed retrospectively regarding 1st-, 2nd- and 3rd-line treatment using descriptive statistics. RESULTS Forty-two patients were eligible for analysis (mean age 62.1 years, 47.6% female). At initial diagnosis, 20 patients (47.6%) were documented with right-sided tumors. Most patients (81.0%) were tested for BRAF before 1st-line. Four patients (9.5%) showed high microsatellite instability (MSI-H). Based on 94 treatment lines, chemotherapy combined with targeted therapy (TT) was used mostly (61.7%), followed by chemotherapy alone (19.1%). Backbone therapies were most frequently FOLFOXIRI (27.7%), FOLFOX/CAPOX (22.3%), or FOLFIRI (20.2%). Anti-VEGF/VEGFR and anti-EGFR-treatments were used in 45.7% and 23.4% of patients, respectively. Across all treatment lines and types, the predominantly documented reason for discontinuation was lack of efficacy. CONCLUSION Combined chemotherapy+TT (anti-VEGF/VEGFR and anti-EGFR) played a predominant role in BRAFV600E-mutated mCRC treatment prior to approval of the targeted combination encorafenib plus cetuximab. Since lack of efficacy was the major reason for treatment discontinuation, newly approved therapies including encorafenib plus cetuximab and - for MSI-H tumors - pembrolizumab represent urgently needed options for future mCRC patients.

3536 Background: We evaluated the prognostic and predictive impact of DNA mutations related to anti-EGFR antibody resistance in patients of the PANAMA trial, which compared Panitumumab (Pmab) and FU/FA versus FU/FA maintenance therapy after Pmab-FOLFOX induction therapy in RAS wild-type (wt) mCRC. Methods: Next generation panel sequencing was conducted on 201 of 248 tumors obtained prior to study inclusion from the full analysis set using the Cancer Hotspot Panel v2 on an Illumina MiSeq system. Hyperselection covered mutations of the following genes: KRAS, NRAS, BRAF, HER2, PTEN, AKT1, PIK3CA. Median progression-free (PFS) and overall survival (OS) since start of maintenance were estimated by Kaplan-Meier and Cox-regression (log rank test). Objective response rates (ORR) of maintenance therapy were compared by Chi-square-test. Results: From 201 tumors, 41 (20.4 %) carried at least one mutation: KRAS: 7 (3.5%), BRAF: 23 (11.4%), PTEN: 4 (2.0%), AKT1: 2 (1.0%), PIK3CA: 12 (6.0%), with 6 tumors harboring co-occuring mutations. No mutations were found in NRAS and HER2. Negative hyperselection (wt for all genes) was associated with (numerically) favourable prognosis in terms of PFS (HR 0.79 (95% CI 0.55 – 1.12), p=0.184), OS (HR 0.61 (95% CI 0.40 – 0.95), p=0.028) and ORR (39.4% vs. 29.3%, p=0.279). The benefit of adding Pmab to FU/FA during maintenance was limited to the hyperselection wt subgroup, with significantly longer PFS (9.9 vs. 6.0 months, 0.64 (95% CI 0,46 – 0.90), p = 0.011), numerically longer OS and significantly higher ORR (49.4% vs 26.6%, p=0.009) compared to FU/FA (Table). Conclusions: Mutations related to resistance concerning anti-EGFR antibodies were detected in 41 of 201 (20.4%) of analysed tumors and associated with a worse prognosis compared to hyperselected wt tumors. Negative hyperselection may aid in the identification of patients with relevant benefit from maintenance therapy including Pmab. [Table: see text]

3626 Background: CRC still is one of the leading causes of cancer related death though prognosis has improved through guideline based management. The COVID-19 pandemic lead to re-allocation of resources subordinating all sections of care for CRC patients. We present data on changes of CRC care during the pandemic from 22 German AIO CC and our high volume Institute of Pathology (pathology). Methods: Data was collected retrospectively comparing the months (mo) of the first wave (fw) (4-6/2020) and second wave (sw) (11-12/2020) of the pandemic with corresponding periods (cp) in 2019 focusing on the number of precancerous (ICD-O/0+2) and malignant (ICD-O/3+6) colorectal lesions (CRL) diagnosed by our pathology, the number/stage of primary diagnoses (PD) and the number of surgeries (surg) at AIO CC. There, quality criteria of CRC care were also assessed (number of PD discussed within a multidisciplinary tumor board (tb), received social service (soc)/ psychological (psy) counseling or recruited into a clinical trial). Statistical analysis was performed using students t-test for paired data. Results: Numbers of CRL detected upon histology (row 1-3), number of cases, surg and quality criteria from AIO CC (row 4-9) are displayed in the table. We saw a dip in diagnosed CRL and number of surg (p=0.007) only during fw, whereas PD dipped significantly in both waves. A significant reduction in diagnosis of stage III CRC was detected for 2019 vs. 2020 (p=0.001), not for other stages. Quality criteria showed a significant reduction in clinical trial inclusion, a small dip in soc/psy counseling and persistently high tb presentation. Conclusions: We detected a significant decrease of premalignant lesions and primary cancers during the first year of the pandemic which may impact cancer mortality in the future. Certified German CC provided CRC care with significant reduction in clinical trial inclusion only, suggesting high stability of established certified cancer care infrastructure.[Table: see text]

PURPOSE The randomized PANAMA trial investigated the efficacy of panitumumab (Pmab) when added to maintenance therapy with fluorouracil and folinic acid (FU/FA) in patients with RAS wild-type metastatic colorectal cancer. METHODS Following first-line induction therapy with six cycles of FU/FA and oxaliplatin plus Pmab, responding patients (stable disease or partial or complete remission) were randomly assigned (1:1, open-label) to maintenance treatment with either FU/FA plus Pmab or FU/FA alone. The primary objective was to demonstrate superiority of progression-free survival (PFS, time from random assignment until progression or death) in favor of FU/FA plus Pmab with a hazard ratio (HR) of 0.75, a power of 80%, and a significance level of 10%. Secondary end points included overall survival, objective response rate of maintenance therapy, and toxicity. Survival end points were analyzed by the Kaplan-Meier method and compared by log-rank test and Cox regressions. Dichotomous variables were compared by Fisher's exact test; odds ratios were indicated when appropriate. The trial is registered with ClinicalTrials.gov ( NCT01991873 ). RESULTS Overall, 248 patients were randomly assigned and received maintenance therapy with either FU/FA plus Pmab (125 patients) or FU/FA alone (123 patients). At data cutoff, with 218 events (of 218 needed), PFS of maintenance therapy was significantly improved with FU/FA plus Pmab (8.8 months v 5.7 months; HR, 0.72; 80% CI, 0.60 to 0.85; P = .014). Overall survival (event rate 54%) numerically favored the FU/FA plus Pmab arm (28.7 months v 25.7 months; HR, 0.84; 95% CI, 0.60 to 1.18; P = .32). Objective response rates were 40.8% in patients receiving FU/FA plus Pmab versus 26.0% in patients receiving FU/FA alone (odds ratio, 1.96; 95% CI, 1.14 to 3.36; P = .02). The most frequent Common Terminology Criteria for Adverse Event grade ≥ 3 event during maintenance therapy was skin rash (7.2%). CONCLUSION In RAS wild-type metastatic colorectal cancer, maintenance therapy with FU/FA plus Pmab induced a significantly superior PFS compared with FU/FA alone. If active maintenance therapy is aspired following induction therapy with FU/FA and oxaliplatin plus Pmab, FU/FA plus Pmab appears to be the most favorable option.

This trial investigates the addition of panitumumab to chemotherapy with fluorouracil/folinic acid and oxaliplatin (FOLFOX) in a 2:1 randomised, controlled, open-label, phase II trial in RAS wild-type colorectal cancer patients with R0/1-resected liver metastases.The primary endpoint was progression-free survival (PFS) two years after randomisation. The experimental arm (12 weeks of biweekly mFOLFOX6 plus panitumumab followed by 12 weeks of panitumumab alone) was considered active if the two-year PFS rate was ≥65%. Based on historical data, a two-year PFS rate of 50% was estimated in the control arm (12 weeks of biweekly FOLFOX). The trial was performed with a power of 80% and an alpha of 0.05. Secondary endpoints included overall survival (OS) and toxicity. The trial is registered with ClinicalTrials.gov, NCT01384994.The full analysis set consists of 70 patients (pts) in the experimental arm and 36 pts in the control arm. The primary endpoint was missed with a two-year PFS of 35.7% with FOLFOX plus panitumumab and 30.6% in the control arm. In comparative analyses, trends towards improved PFS (HR 0.83; 95%CI, 0.52-1.33; P = 0.44) and OS (HR 0.70; 95% CI, 0.34-1.46; P = 0.34) were observed in favour of the panitumumab-based study arm. No new or unexpected safety signals were observed with FOLFOX plus panitumumab following liver resection.The PARLIM trial failed to demonstrate a two-year PFS rate of 65% after resection of colorectal liver metastases. The positive trends in survival endpoints may support future trials evaluating treatment with anti-EGFR agents after resection of liver metastases.

4 Background: Trifluridine/tipiracil (FTD/TPI) plus bevacizumab (Bev) demonstrated promising efficacy in a randomized phase 2 trial of heavily pretreated patients (pts) with metastatic colorectal cancer (mCRC). SUNLIGHT was conducted to confirm these findings. Methods: The global phase 3 SUNLIGHT study enrolled pts aged ≥18 years with histologically confirmed mCRC, ECOG PS 0/1, and treated with 1-2 prior chemotherapy regimens in an advanced setting, including fluoropyrimidines, irinotecan, oxaliplatin, an anti-VEGF monoclonal antibody (if medically considered) and/or anti-EGFR monoclonal antibody for RAS wild-type tumors. Pts were randomised (1:1) to receive FTD/TPI (35 mg/m2 twice daily on days 1–5 and 8–12 of each 28-day cycle) alone or combined with Bev (5 mg/kg on days 1 and 15). Primary endpoint was overall survival (OS). Results: Between Nov 2020 and Feb 2022, 492 pts were randomised to receive FTD/TPI + Bev (n = 246) or FTD/TPI (n = 246). Baseline characteristics were balanced between arms. FTD/TPI + Bev significantly extended OS over FTD/TPI, median OS was 10.8 months vs 7.5 months, respectively (HR, 0.61; 95% CI, 0.49, 0.77; P< 0.001). OS rates at 12 months were 43% in the FTD/TPI + Bev arm and 30% in the FTD/TPI arm. Median progression-free survival was 5.6 months in the FTD/TPI + Bev arm and 2.4 months in the FTD/TPI arm (HR, 0.44; 95% CI, 0.36,0.54; P< 0.001). Grade ≥3 adverse events (AEs) were not significantly increased in the FTD/TPI + Bev arm vs the FDT/TPI arm (72.4% vs 69.5%). No new safety signals were noted. Conclusions: FTD/TPI + Bev provided a statistically significant and a clinically meaningful 3.3-month improvement in OS, extending mOS up to 10.8 months, with a 39% reduction in the HR of death in pts with refractory mCRC and with a predictable and acceptable safety profile. Clinical trial information: NCT04737187 .

127 Background: Despite molecular selection, patients with RAS wildtype mCRC represent a heterogeneous population, including different metastatic patterns and number of organs involved. We investigated metastatic patterns for their prognostic and predictive impact on maintenance therapy with (FU/FA plus Pmab or FU/FA alone) in patients treated within the PanaMa trial. Methods: The study population was stratified according to number of organs involved and also to different patterns including liver metastases alone or in combination with additional organs. Kaplan-Meier method and Cox regressions were used to correlate efficacy endpoints (i.e. progression-free survival (PFS) and overall survival (OS) of maintenance therapy) in the aforementioned populations. Results: Of 248 patients (pts) receiving maintenance therapy, 133 pts had a one-metastatic site disease (53.6%). Of those, 102 pts had liver-only metastases. Furthermore, liver metastases plus one additional involved organ was observed in 61/248 patients (24.6%), and liver metastases plus two or more organs in 40/248 patients (16.1%). In general, one organ disease was associated with favourable PFS of maintenance therapy compared to patients with ≥2 organs involved (HR 0.68, 95% CI 0.52–0.88; P = 0.004). A predictive impact of disease spread in terms of pmab-containing maintenance therapy was present for the PFS of maintenance therapy in patients with ≥ 2 organ disease (HR 0.58, 95% CI 0.39–0.86; P = 0.006) unlike in patients with only one-organ disease (HR 0.83, 95% CI, 0.57-1.21; P = 0.332) and also specifically in patients with a 2-organ disease including the liver (HR 0.57, 95% CI 0.33–0.99; P = 0.046). Conclusions: Consistent with previous reports, organ spread has prognostic impact in mCRC. The efficacy of more intensive maintenance therapy (including pmab and 5-FU/FA) is predominantly seen in patients with more than one organ involved in the metastatic spread, while less striking effects were seen in patients with only one organ disease. These data may support clinical decisions when EGFR-based maintenance therapy is considered. Clinical trial information: NCT01991873 .

100 Background: FIRE-4 (AIO KRK-0114) is performed in RAS wild-type (wt) mCRC patients. This randomized study tests the efficacy of early switch maintenance during 1st-line therapy (part 1) and re-challenge with cetuximab (part 2) in later-line treatment. In part 1, all patients received first-line induction treatment with FOLFIRI plus cetuximab (FOLFIRI/Cet). In arm A, patients were randomized to continue FOLFIRI/Cet until progression or intolerable toxicity. In arm B, patients received FOLFIRI/Cet for 8-12 cycles, after which maintenance therapy with 5-FU/FA plus bevacizumab (5-FU/Bev) was applied. The first randomization evaluates the question if an early switch from cetuximab to bevacizumab during maintenance therapy may prolong PFS. The study protocol explicitly allowed a first cycle of chemotherapy to be applied before randomization. Methods: Within this randomized, controlled, open-label phase-III study, patients received FOLFIRI (irinotecan plus 5-FU/FA) plus cetuximab every two weeks at the standard dosing schedule. In arm A, FOLFIRI plus cetuximab was continued until progression or intolerable toxicity. De- and re-escalation was allowed according to the local standard of care. In arm B, patients received 8 cycles of FOLFIRI plus cetuximab (in case of tumor response) or 12 cycles (in case of stable disease) followed by maintenance with 5-FU/FA plus bevacizumab (5mg/kg) until disease progression or intolerable toxicity. Overall survival after second randomization (part 2) is evaluated as a primary endpoint. Here, we report PFS in first-line (part 1) as a secondary study endpoint of the study. Other secondary endpoints included ORR, OS, safety, and tolerability. Results: From August 2015 to January 2021, 672 patients were randomized, and 656 patients were assigned to treatment in 120 German and 10 Austrian centers (327 arm A and 329 in arm B). Of those, 205 patients received one cycle of FOLFIRI alone before randomization. In both arms, ORR was comparable for patients receiving cetuximab from the first cycle when compared to those receiving one cycle of chemotherapy only (arm A: 58.7% vs 62.9% (p = 0.54), arm B 60.2% vs 55.6% (p = 0.48). PFS was also not influenced in both arms (arm A: 10.8mo vs. 10.6mo (p = 0.91); arm B 11.2mo vs. 11.4mo (p = 0.62)). Preliminary results suggest that also OS (event rate 38.3%) was not influenced by one cycle applied without cetuximab (arm A: 33.7 mo vs. 29.1 mo (p = 0.20); arm B: 35.6 mo vs. 28.9 mo (p = 0.13)). Conclusions: Application of one initial cycle with chemotherapy alone did not influence the efficacy of a first-line strategy of FOLFIRI plus cetuximab. If RAS mutational analysis is not timely available, a start with FOLFIRI alone adding cetuximab in cycle 2 seems to be safe with respect of overall efficacy. Clinical trial information: NCT02934529 .

51 Background: The PANAMA study demonstrated superior progression-free survival (PFS) with the addition of panitumumab (Pmab) to fluorouracil and folinic acid (FU/FA) as maintenance therapy following first-line induction therapy with FOLFOX/Pmab in patients with RAS wild-type metastatic colorectal cancer. We report health-related quality of life (HRQOL) analyses of the PANAMA study. Methods: HRQOL was assessed by European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) at every cycle of therapy until disease progression. All patients who received at least one dose of induction therapy and completed at least one HRQOL assessment were included into the analysis. HRQOL outcomes were mean changes in EORTC QLQ-C30 from baseline (prior to cycle 1 of induction therapy) to each cycle of treatment (both induction and maintenance therapy). The trial is registered with ClinicalTrials.gov (NCT01991873). Results: In total, 349/377 (93%) of the induction and 237/248 pts (96%) of the maintenance group completed at least one HRQOL assessment and were included in the HRQOL analysis population. There were no significant differences in any of the EORTC QLQ-C30 items between both treatment arms before induction therapy and at randomization. From baseline to cycle 6 of induction therapy there was significant improvement in mean EORTC QLQ-C30 global health status (GHS)/QOL, functioning (except for cognitive functioning) and symptom (except for nausea and vomiting, dyspnea, appetite loss, constipation, and financial difficulties) scores in the randomized population. During maintenance therapy, no significant differences between FU/FA plus Pmab and FU/FA alone were observed. In both arms of the trial, GHS/QOL scores were maintained or trended to improve from baseline (start of induction therapy) to cycle 10 of maintenance therapy (FU/FA plus Pmab: mean difference 9.48 [95% CI 1.96-17.00]; p=0.014); FU/FA arm (mean difference 6.52 [95% CI –1.9-14.95]; p=0.128). Conclusions: Using the established EORTC QLQ-C30 assessment, the addition of Pmab to FU/FA as maintenance therapy in patients with RAS wild-type metastatic colorectal cancer did not impair the HRQOL endpoints analyzed compared to FU/FA alone. These results, along with previously reported improvement in PFS, may support clinical decision-making concerning maintenance treatments. Clinical trial information: NCT01991873 .

PURPOSE This trial investigated the addition of panitumumab to triplet chemotherapy with fluorouracil/folinic acid, oxaliplatin, and irinotecan (FOLFOXIRI) in a two-to-one randomized, controlled, open-label, phase II trial in patients with untreated RAS wild-type (WT) metastatic colorectal cancer. PATIENTS AND METHODS The primary end point was objective response rate (ORR) according to RECIST (version 1.1). The experimental arm (modified FOLFOXIRI [mFOLFOXIRI] plus panitumumab) was considered active if the ORR was ≥ 75%. The experimental ORR was compared with an estimated ORR of 60% based on historical data, verified by a randomized control group (FOLFOXIRI). The power of the trial was 80%, with a potential type I error of 0.05. Secondary end points included secondary resection rate, toxicity, progression-free survival, and overall survival. RESULTS A total of 63 patients were randomly assigned to the experimental arm and 33 patients to the control arm. The ORR of the mFOLFOXIRI plus panitumumab arm exceeded 75% and was higher when compared with that of FOLFOXIRI (87.3% v 60.6%; odds ratio, 4.469; 95% CI, 1.61 to 12.38; P = .004). The secondary resection rate was improved with the addition of panitumumab (33.3% v 12.1%; P = .02). Progression-free survival was similar in the study arms, whereas overall survival showed a trend in favor of the panitumumab-containing arm (hazard ratio for death, 0.67; 95% CI, 0.41 to 1.11; P = .12). CONCLUSION The addition of panitumumab to mFOLFOXIRI in patients with RAS WT metastatic colorectal cancer improved the ORR and rate of secondary resection of metastases and represents a treatment option in selected and fit patients in need of highly active first-line therapy. Future studies should determine whether the addition of panitumumab to mFOLFOXIRI prolongs survival.

BACKGROUND: FIRE-3 compared first-line therapy with FOLFIRI plus either cetuximab or bevacizumab in 592 KRAS exon 2 wild-type metastatic colorectal cancer (mCRC) patients. The consensus molecular subgroups (CMS) are grouping CRC samples according to their gene-signature in four different subtypes. Relevance of CMS for the treatment of mCRC has yet to be defined. PATIENTS AND METHODS: In this exploratory analysis, patients were grouped according to the previously published tumor CRC-CMSs. Objective response rates (ORR) were compared using chi-square test. Overall survival (OS) and progression-free survival (PFS) times were compared using Kaplan-Meier estimation, log-rank tests. Hazard ratios (HR) were estimated according to the Cox proportional hazard method. RESULTS: CMS classification could be determined in 438 out of 514 specimens available from the intent-to-treat (ITT) population (n = 592). Frequencies for the remaining 438 samples were as follows: CMS1 (14%), CMS2 (37%), CMS3 (15%), CMS4 (34%). For the 315 RAS wild-type tumors, frequencies were as follows: CMS1 (12%), CMS2 (41%), CMS3 (11%), CMS4 (34%). CMS distribution in right- versus (vs) left-sided primary tumors was as follows: CMS1 (27% versus 11%), CMS2 (28% versus 45%), CMS3 (10% versus 12%), CMS4 (35% versus 32%). Independent of the treatment, CMS was a strong prognostic factor for ORR (P = 0.051), PFS (P

ZusammenfassungDie onkologische Therapieführung des metastasierten Darmkrebs (mKRK) erfolgt in enger Kooperation mit anderen Fachdisziplinen, insbesondere der Chirurgie. Trotz Metastasierung können durch interdisziplinäre Behandlungen hier Langzeitverläufe ermöglicht werden, auch wenn die Erkrankung in der Mehrzahl der Fälle (unabhängig vom Behandlungspfad) nicht geheilt werden kann. Die rein onkologische Systemtherapie stützt sich derzeit vor allem auf Chemotherapiekombinationen und monoklonale Antikörper gegen VEGF (Vascular endothelial Growth Factor) und EGFR (Epidermal Growth Factor Receptor), die zu unterschiedlichen Regimen zusammengesetzt werden. Für die EGFR-Antikörper besteht mit den verschiedenen RAS-Mutationen ein negativer prädiktiver Biomarker, der aktuell durch die Beachtung der Primärtumorseite ergänzt wird. In späteren Therapielinien eröffnet sich derzeit die Möglichkeit einer personalisierten Therapie von Subgruppen. Hier sind insbesondere Patienten mit BRAF-V600E-Mutation (BRAF-inhibitorbasierte Kombinationen), Her2-positivem mKRK und Patienten mit MSI-H-Tumor (Checkpointinhibitoren) zu nennen.

Panitumumab is approved for RAS wild‐type metastatic colorectal cancer and was evaluated in Phase III (PRIME, NCT00364013) and Phase II (PEAK, NCT00819780) first‐line randomised studies. This retrospective analysis of these trials investigated efficacy and toxicity of panitumumab‐based maintenance after oxaliplatin discontinuation in RAS wild‐type patients. First‐line regimens were FOLFOX4 ± panitumumab in PRIME and mFOLFOX6 plus panitumumab or mFOLFOX6 plus bevacizumab in PEAK. Outcomes included median progression‐free survival (PFS) and overall survival (OS), from randomisation and oxaliplatin discontinuation, and toxicity. Overall, median duration of panitumumab plus 5‐fluorouracil/leucovorin (5‐FU/LV) maintenance was 21 (interquartile range: 11–41) weeks; that of 5‐FU/LV ± bevacizumab maintenance was 16 (6–31) weeks. Median OS from randomisation was 40.2 (95% confidence interval: 30.3–50.4) and 39.1 (34.2–63.0) months for panitumumab plus 5‐FU/LV maintenance and 24.1 (17.7–33.0) and 28.9 (21.0–32.0) months for 5‐FU/LV ± bevacizumab maintenance in PRIME and PEAK, respectively. Median PFS from randomisation was 16.6 (11.3–23.6) and 15.4 (11.6–18.4) months for panitumumab plus 5‐FU/LV maintenance and 12.6 (9.4–16.2) and 13.1 (9.5–16.6) months for 5‐FU/LV ± bevacizumab maintenance in PRIME and PEAK, respectively. From oxaliplatin discontinuation, median OS was 33.9 (24.7–42.8) and 33.5 (24.5–54.9) months for panitumumab plus 5‐FU/LV maintenance and 16.4 (12.4–24.1) and 23.3 (15.7–26.3) months for 5‐FU/LV ± bevacizumab maintenance in PRIME and PEAK, respectively; PFS was 11.7 (7.8–19.2) and 9.7 (5.8–14.8) months and 7.1 (5.6–10.2) and 7.0 (3.9–10.6) months, respectively. The most frequently reported adverse events were rash, fatigue and diarrhoea. Maintenance of panitumumab plus 5‐FU/LV after oxaliplatin discontinuation was well tolerated and may be an acceptable treatment paradigm for patients demonstrating a good response to first‐line treatment. Prospective studies are warranted., What's new? Panitumumab is an anti‐EGFR antibody used in the treatment of RAS wild‐type metastatic colorectal cancer. But is it useful for long‐term therapy in these patients, especially after more toxic therapies like oxaliplatin are discontinued? In this retrospective analysis, the authors found that a maintenance regimen including panitumumab was well tolerated and may be associated with better outcomes than non‐panitumumab strategies. Patients who received panitumumab‐based maintenance therapy were also more likely to have had a good response to first‐line treatment. The results from this study indicate that further, prospective studies are warranted.

Upfront KRAS and NRAS gene testing (‘RAS’) is the standard of care for metastatic colorectal cancer (mCRC), to guide first-line treatment. The presence of RAS mutation (MT) is a negative predictor for the efficacy of anti-EGFR antibodies and the use of cetuximab and panitumumab is restricted to RAS wild-type (WT) mCRC. Conversion from RAS WT to RAS MT mCRC after treatment with anti-EGFR antibodies is a known and well-described acquired resistance mechanism. The by far less frequent ‘NeoRAS wild-type’ phenomenon (reversion from RAS MT to RAS WT) has recently drawn attention. The proposed effect of chemotherapy on RAS status in mCRC patients is not fully understood. Because of the intriguing biological consequence of a RAS MT to RAS WT reversion, subsequent treatment of NeoRAS WT patients with anti-EGFR antibodies is increasingly being discussed. Here, we report three clinical cases of NeoRAS WT mCRC patients, which received standard-of-care regimens for RAS MT mCRC. Anti-EGFR antibodies were used in two out of three patients after progression of the disease. One of the patients had a long-term response. In line with our observations, NeoRAS WT phenomenon occurs in clinical practice. Retesting of RAS status during treatment should be discussed in patients with unusual long-term clinical courses of RAS MT mCRC to optimise treatment strategy and to evaluate the use of anti-EGFR antibodies.

BackgroundPrimary tumor location (left vs. right) has prognostic and predictive impact on the therapeutic management of metastatic colorectal cancer (mCRC) in particular in the context of anti-epithelial growth factor receptor (anti-EGFR) antibodies. This analysis evaluates the relevance of exact segment-by-segment tumor location in patients with metastatic colorectal cancer on outcome and efficacy of anti-EGFR-antibodies.MethodsThis is a retrospective, pooled analysis of five randomized clinical trials (FIRE-1, CIOX, FIRE-3, XELAVIRI and VOLFI) treating metastatic colorectal cancer patients in a first-line setting, published between 2011-2019. Each trial was a multicentre, phase 2 or phase 3 trial in which patients with untreated metastatic colorectal cancer received chemotherapy regimens with or without monoclonal antibodies (anti-VEGF, anti-EGFR). Eligible were patients with histologically confirmed metastatic colorectal cancer in good performance status who were at least 18 years old. Individual data of 1809 patients with available exact primary tumor location were included into this analysis. Prognostic and predictive effects of primary tumor location were evaluated in uni- and multivariate analyses using the Kaplan Meier method, log rank tests, Cox regressions and logistic regressionsResults Exact primary tumor location is an important determinant of overall survival (OS) in mCRC patients (PConclusions Primary tumor location of metastatic colorectal cancer affects prognosis. Anti-EGFR efficacy increases continuously from proximal to distal segments of the colorectum in metastatic colorectal cancer patients with RAS/BRAF wild-type and BRAF mutant tumors. Therefore, patients with BRAF mutant tumors of the distal segments may benefit from first-line Anti-EGFR-based therapy.Trial registrationFIRE1 trial registration ID n/aCIOX trial registration ID NCT00254137FIRE3 trial registration ID NCT00433927XELAVIRI trial registration ID NCT01249638VOLFI trial registration ID NCT01328171

Journal of Clinical Medicine 10(3), 490 (2021). doi:10.3390/jcm10030490 special issue: "Special Issue "Pancreatic Cancer: Challenges and Breakthroughs" / Special Issue Editor: Dr. Maria Del Pilar Acedo Nunez, Guest Editor", Published by MDPI, Basel

Background Cytoreductive surgery (CRS) in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) represents a multimodal treatment concept for patients with peritoneal surface malignancies. The use of intraperitoneal cisplatin (CDDP) is associated with a risk of acute kidney injury (AKI). The aim of this study is to evaluate the protective effect of perioperative sodium thiosulfate (STS) administration on kidney function in patients undergoing CRS and CDDP-based HIPEC. Patients and Methods We retrospectively analyzed clinical data of all patients who underwent CRS and CDDP-based HIPEC at our hospital between March 2017 and August 2020. Patients were stratified according to the use of sodium thiosulfate (STS vs. no STS). We compared kidney function and clinical outcome parameters between both groups and determined risk factors for postoperative AKI on univariate and multivariate analysis. AKI was classified according to acute kidney injury network (AKIN) criteria. Results Of 238 patients who underwent CRS and CDDP-based HIPEC, 46 patients received STS and 192 patients did not. There were no significant differences in baseline characteristics. In patients who received STS, a lower incidence (6.5% vs. 30.7%; p = 0.001) and severity of AKI (p = 0.009) were observed. On multivariate analysis, the use of STS (OR 0.089, p = 0.001) remained an independent kidney-protective factor, while arterial hypertension (OR 5.283, p p = 0.032) were predictors for postoperative AKI. Conclusions The present data suggest that STS protects patients from AKI caused by CRS and CDDP-based HIPEC. Further prospective studies are needed to validate the benefit of STS among kidney-protective strategies.

Secondary resection of metastases is recommended in metastatic colorectal cancer (mCRC). Data describing changes in mutational profiles of corresponding primary tumor and metastatic tissue after conversion treatment are limited. Next generation sequencing was performed in formalin-fixed mCRC samples from patients of the FIRE-3 trial (FOLFIRI plus cetuximab or bevacizumab) before treatment start (baseline) and after secondary resection of metastases (post baseline). Changes of mutational profiles and tumor mutational burden (TMB) were assessed within a post-hoc analysis. Median overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were compared between treatment arms. Paired tumor samples were obtained from 25 patients (19 RAS wild-type, 6 RAS mutant by pyrosequencing). ORR (92.0% vs 58.0%) and OS (60.8 vs 35.4 months, hazard ratio = 0.39 [95% CI 0.14-1.12], P = .08) were higher for patients receiving cetuximab. After conversion therapy, 56 alterations (42 in the cetuximab and 14 in the bevacizumab arm) were newly observed in 18 patients (9 each treated with cetuximab or bevacizumab). Gains (n = 21) and losses (n = 21) of alterations occurred during cetuximab-based treatment, while mainly gains of alterations occurred during bevacizumab (n = 10). Three of nine patients treated with cetuximab that presented a change of mutational profiles, developed resistance to cetuximab. Mutational profiles were largely comparable before and after treatment with anti-VEGF or anti-EGFR directed monoclonal antibodies after secondary resection. Mutations associated with resistance to anti-EGFR antibodies were observed in only one-third of patients.

3502 Background: FIRE-4.5 (AIO KRK-0116) compared FOLFOXIRI plus either cetuximab or bevacizumab in BRAF V600E-mutant metastatic colorectal cancer (mCRC) patients not treated for metastatic disease before. Methods: Within this 1:2 randomized, controlled, open-label phase-II study, patients received FOLFOXIRI every two weeks at the following schedule: irinotecan 150mg/m² (30-90min, day 1), folinic acid 400mg/m² (120min, day 1), oxaliplatin 85mg/m² (120 min, day 1), followed by 5-fluorouracil 3,000 mg/m², 48h. FOLFOXIRI was combined with either bevacizumab (arm A) at a dose of 5mg/kg body weight, every 2 weeks or cetuximab (arm B) at a loading dose of 400mg/m² and subsequent weekly doses of 250mg/m². FOLFOXIRI was applied for a maximum of 12 cycles before maintenance treatment was recommended. Primary endpoint was superiority of Arm B with respect to overall response rate (ORR) according to RECIST 1.1 criterions. Secondary endpoints included PFS, OS, and tolerability. Results: From November 2016 to December 2020 108 patients were randomized in 90 German and 10 French centers (35 arm A and 73 in arm B). No new or unexpected toxicities were observed. Primary endpoint was not met with an ORR of 66.7% and 52.0% (p =0.23) in the respective arms. Median PFS was significantly longer in arm A vs arm B (8.3 months vs 5.9 months; logrank p = 0.03; HR 1.8). While OS data is still immature, median OS time are comparable at the time of analysis. Patients with left-sided primary tumors had comparable results with either bevacizumab or cetuximab, whereas those with right-sided primary tumors showed a trend towards better efficacy of the bevacizumab combination. Updated results will be presented at the annual meeting. Conclusions: FIRE-4.5 is the first prospective and randomized study investigating efficacy of FOLFOXIRI combined with targeted therapy in the first-line treatment of BRAF V600E-mutant mCRC. FOLFOXIRI plus either bevacizumab or cetuximab have comparable efficacy with differential effects according to primary tumor sidedness supporting the heterogeneity of BRAF V600E-mutant subpopulation of mCRC. Clinical trial information: NCT04034459.

Pancreatic ductal adenocarcinoma (PDAC) represents one of the most fatal malignancies worldwide. It is suggested that survival in PDAC depends, among other things, on pattern of disease recurrence.We performed a pooled analysis of the adjuvant therapy studies CONKO-001, CONKO-005, and CONKO-006, including a total of 912 patients with regard to prognostic factors in patients with recurrent disease. Overall survival from disease recurrence (OS 2) and disease-free survival (DFS) from the day of surgery were expressed by Kaplan-Meier method and compared using log-rank testing and Cox regression.Of 912 patients treated within the previously mentioned CONKO trials, we identified 689 patients with disease recurrence and defined site of relapse. In multivariable analysis, the presence of isolated pulmonary metastasis, low tumour grading, and low postoperative level of CA 19-9 remained significant factors for improved OS 2 and DFS. Furthermore, completeness of adjuvant gemcitabine-based treatment (OS 2: P = 0.006), number of relapse sites (OS 2: P = 0.015), and type of palliative first-line treatment (OS 2: P 0.001) significantly affected overall survival after disease recurrence in PDAC.Determining tumour subgroups using prognostic factors may be helpful to stratify PDAC patients for future clinical trials. In case of disease recurrence, the site of relapse may have a prognostic impact on subsequent survival. Further investigations are needed to identify differences in tumour biology, reflecting relapse patterns and the differing survival of PDAC patients.

XELAVIRI compared sequential (Arm A) versus initial (Arm B) irinotecan in combination with fluoropyrimidine plus bevacizumab in patients with metastatic colorectal cancer, trial identification: NCT01249638. In the full analysis set of the study, non-inferiority of time to failure of strategy (TFS) was not shown. The present analysis was performed to evaluate the effect of gender on treatment outcome and tolerability.The study end-points overall response rate (ORR), progression-free survival (PFS), TFS and overall survival (OS) were evaluated in female versus male patients and in molecular subgroups (i.e. RAS mutational status). Interaction of treatment and gender was tested by likelihood ratio tests.In total, 281 male and 140 female patients (n = 421) were evaluated. Among the male patients, the ORR was 33.6% without and 58.3% with initial irinotecan (P 0.001). PFS (hazard ratio [HR] 0.54; 95% confidence interval [CI] 0.42-0.69; P 0.001) and OS (HR 0.63; 95% CI 0.47-0.85; P = 0.002) were also significantly better with initial irinotecan. Among the female patients, the ORR was 42.7% in Arm A and 43.1% in Arm B, PFS was similar (HR 1.09; 95% CI 0.76-1.55; P = 0.649) without and with initial irinotecan. A strong trend for inferior outcome with regard to OS with initial irinotecan was observed (HR 1.46; 95% CI 0.95-2.24; P = 0.081) and the trend reached significance in the multivariate analysis (HR 1.78; 95% CI 1.08-2.95; P = 0.02). Formal interaction of treatment and gender was observed for ORR (P = 0.018), PFS (P = 0.002) and OS (P = 0.001). Treatment-related adverse events were not significantly different between male and female patients.The present analysis suggests that gender interacts with efficacy of initial irinotecan when used in combination with fluoropyrimidines and bevacizumab. Although male patients derived a significant and clinically meaningful benefit from initial combination chemotherapy, this was not observed in female patients.

BackgroundB cells and tertiary lymphoid structures (TLS) are reported to be important in the improvement of survival of cancer patients. These secondary lymphoid organs have been associated with the generation of an anti-tumor response. Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancer types and the stromal architecture shapes the intratumoral heterogeneity. The stroma of PDAC is a complex system in which crosstalk takes place between cancer-associated fibroblasts, immune cells, endothelial cells and the cancer cells. Besides immune cells and fibroblasts, there is some limited data about the influence of nerve fibers on cancer progression.Patients and methodsNerve Fiber Density (NFD) was analysed in our cohort of 188 patients with Pancreatic Ductal Adenocarcinoma who underwent pancreatic surgery. We used immunohistochemistry and multiplex imaging to phenotype the immune cell infiltrate. The cell detection classifier measured distance from immune cell to cancer gland and with a heat map we could count TLS. By using Machine learning we were able to define the spatial distribution and counting Tertiary Lymphoid Structures.ResultsHigh NFD is significantly associated with prolonged overall survival (HR 1.676 (95%CI 1.126,2.495) for low vs. high NFD, p-value 0.0109). The immune cells surrounding the nerve fibers were phenotyped in B cells, T cells and dendritic follicular cells, matching a TLS. Here we show that small nerve fibers are located at the TLS in Pancreatic Cancer and a high Nerve Fiber Density combined with more than 5 TLS is associated with a better survival (HR 0.388 (95%CI 0.218, 0.689).ConclusionThe co-localization of small nerve fibers with TLS is a new finding which has not been described before. However the precise roles of these TLS and nerve fibers remains unknown. These findings unravel future pathways and has the potential to reach new directions into already existing targeted therapy.

Magnesium wasting is a frequent side effect of epidermal growth factor receptor (EGFR)-antibody treatment as magnesium-absorption mechanisms are dependent on EGFR signaling. EGFR-inhibition results in decreased renal reabsorption. There is evidence that hypomagnesemia during cetuximab treatment correlates with response. The prognostic role of hypomagnesemia during bevacizumab treatment has not been studied yet. Here, we evaluate the prognostic value of hypomagnesemia in patients with metastatic colorectal cancer treated with FOLFIRI plus cetuximab or bevacizumab as first-line therapy. A total of 391 of 752 patients of the firstline irinotecan study population had magnesium levels measured at baseline and for the first three cycles (6 weeks) of treatment. Of those, 240 had Rat Sarkoma wildtype tumors. Overall hypomagnesemia was more common in the cetuximab compared to the bevacizumab arm (80 vs. 43%, P < 0.005). During therapy, magnesium showed a time-dependent decrease to 80% of baseline in the cetuximab and to 89% in the bevacizumab arm. Whereas magnesium continued to decrease over time in the cetuximab-treated patients, it remained stable in the bevacizumab-treated. Overall response rate (ORR) was associated with higher magnesium at week 6 (20.9 vs. 79.1%, P = 0.041). Bevacizumab-treated patients with magnesium levels below the median value at week 6 had a significantly longer progression-free survival (PFS; 11.7 vs. 9.9 months, P = 0.034; hazard ratio 0.73) and a trend towards longer overall survival (OS) (29.6 vs. 23.2 months, P = 0.089; hazard ratio 0.77). Hypomagnesemia at predefined time points and magnesium nadir had no significant effect on ORR, OS and PFS in the cetuximab arm. Our data show different magnesium kinetics in patients with metastatic colorectal cancer treated with cetuximab or bevacizumab. For patients treated with cetuximab, hypomagnesemia did not have an impact on response and survival. Hypomagnesemia might have a prognostic value in bevacizumab treatment.