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Background and Purpose: Neoadjuvant short-course radiotherapy (SCRT) followed by full-dose systemic chemotherapy is an established treatment modality in locally advanced rectal cancer (LARC). Until recently, SCRT has been exclusively delivered with photons. Proton beam therapy (PBT) may minimize acute toxicity, which in turn likely impacts favorably on the tolerability to subsequent chemotherapy. The aim of this study is a dosimetric comparison between SCRT with photons and protons in the randomized phase II trial PRORECT (NCT04525989)., Materials and Methods: From June 2021 to June 2022, twenty consecutive patients with LARC have been treated according to study protocol. For each patient, both a VMAT and a PBT treatment plans have been generated and compared pairwise., Results: Dose-volume histogram (DVH) analysis revealed that SCRT with protons significantly reduced radiation dose to pelvic organs at risk including bladder, bones, and bowel in comparison to SCRT with photons. Photon and proton treatment plans had equivalent conformity and homogeneity indexes., Conclusion: Preoperative SCRT with protons offers a significant reduction of radiation dose to normal tissues compared with current photon-based radiotherapy technique. Demonstrated dosimetric advantages may translate into measurable clinical benefits in patients with LARC. Clinical implications of the dosimetric superiority of SCRT with protons will be presented in the coming reports from the PRORECT trial., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Background: Preoperative chemoradiotherapy (CRT) followed by total mesorectal excision is widely accepted as the standard of care for high-risk rectal cancer. Adjuvant chemotherapy is advised in several international guidelines, although the survival benefit remains unclear and compliance is poor. The current multidisciplinary approach has led to major improvements in local control, yet the occurrence of distant metastases has not decreased accordingly. The combination of short-course radiotherapy (SCRT) and chemotherapy in the waiting period before surgery might have several benefits, including higher compliance, downstaging and better effect of systemic therapy., Methods: This is an investigator-initiated, international multicentre randomized phase III trial. High-risk rectal cancer patients were randomized to SCRT followed by chemotherapy (6 cycles CAPOX or alternatively 9 cycles FOLFOX4) and subsequent surgery, or long-course radiotherapy (25-28 × 2-1.8 Gy) with concomitant capecitabine followed by surgery and optional postoperative chemotherapy (8 cycles CAPOX or 12 cycles FOLFOX4) according to local institutions' policy. The primary endpoint is time to disease-related treatment failure. Here, we report the compliance, toxicity and postoperative complications in both study groups., Findings: Between June 2011 and June 2016, 920 patients were enrolled. Of these, 901 were evaluable (460 in the experimental arm and 441 in the standard arm). All patients in the experimental arm received 5 × 5 Gy radiotherapy, and 84% of all patients received at least 75% of the prescribed chemotherapy. In the standard arm, the compliance for CRT was 93% and 58% for postoperative chemotherapy. Toxicity ≥grade 3 occurred in 48% of patients in the experimental arm, compared to 25% of patients in the standard arm during preoperative treatment and 35% of patients during postoperative chemotherapy. No statistically significant differences in surgical procedures or postoperative complications were observed., Interpretation: High compliance (84%) of preoperative systemic treatment could be achieved with the experimental approach. Although considerable toxicity was observed during preoperative therapy, this did not lead to differences in surgical procedures or postoperative complications. Longer follow-up time is needed to assess the primary endpoint and related outcomes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Radiotherapy (RT) for rectal cancer can have adverse effects on testicular function resulting in azoospermia and low testosterone levels. Variability of testicular dose (TD) due to differences in position of testes has been assessed with scrotal dosimeters and resulted in substantial variability of delivered TD. The aim of this study was to estimate planned and delivered TD using a treatment planning system (TPS)., Methods: In 101 men treated with RT for rectal cancer the cumulative mean TD (mTD) was calculated by TPS based on plan-computed tomography (CT) to evaluate the effect of different predictors on planned TD. The delivered TD was estimated by TPS based on repeated cone-beam CTs in 32 of 101 men to assess within-person variability of planned and delivered TD in a longitudinal analysis., Results: The median planned mTD for short course RT was 0.57 Gy (range 0.06-14.37 Gy) and 0.81 Gy (range 0.36-10.80 Gy) for long course RT. The median planned mTD was similar to the median delivered mTD in the 32 men analysed over the entire course of RT (p=0.84). The mTD did not change significantly over time of planning and delivering RT. The variation in proximity between testes and planning target volume (PTV) was related to within-person variability of mTD in men on the 50th and 75th percentile of mTD and as expected the absolute difference between planned and delivered mTD increased with higher mTD., Conclusion: Testicular doses calculated based on plan-CT are an accurate estimation of delivered TD based on repeated cone beam (CB)CT. The within-person variability of TD is related to variation in proximity between testes and PTV in men with moderate to high TD.

Background: Polymorphisms of genes encoding the Fcy receptors (Fc fragment of IgG receptor 2A (FCGR2A) and 3A (FCGR3A)), which influence their affinity for the Fc fragment, have been linked to the pharmacodynamics of monoclonal antibodies. Most studies have been limited by small samples sizes and have reported inconsistent associations between the FCGR2A and the FCGR3A polymorphisms and clinical outcome in metastatic colorectal cancer (mCRC) patients treated with cetuximab. We investigated the association of these polymorphisms and clinical outcome in a large cohort of mCRC patients treated with first-line 5-fluorouracil/folinic acid and oxaliplatin (Nordic FLOX) +/- cetuximab in the NORDIC-VII study (NCT00145314)., Methods: 504 and 497 mCRC patients were evaluable for the FCGR2A and FCGR3A genotyping, respectively. Genotyping was performed on TaqMan ABI HT 7900 (Applied Biosystems, Foster City, CA, USA) with pre-designed SNP genotyping assays for FCGR2A (rs1801274) and FCGR3A (rs396991)., Results: The response rate for patients with the FCGR2A R/R genotype was significantly increased when cetuximab was added to Nordic FLOX (31% versus 53%, interaction P = 0.03), but was not significantly different compared to the response rate of patients with the FCGR2A H/H or H/R genotypes given the same treatment. A larger increase in response rate with the addition of cetuximab to Nordic FLOX in patients with KRAS mutated tumors and the FCGR2A R/R genotype was observed (19% versus 50%, interaction P = 0.04). None of the FCGR3A polymorphisms were associated with altered response when cetuximab was added to Nordic FLOX (interaction P = 0.63). Neither of the FCGR polymorphisms showed any significant associations with progression-free survival or overall survival., Conclusion: Patients with KRAS mutated tumors and the FCGR2A R/R polymorphism responded poorly when treated with chemotherapy only, and experienced the most benefit of the addition of cetuximab in terms of response rate.

Purpose: The NORDIC-VII multicenter phase III trial investigated the efficacy of cetuximab when added to bolus fluorouracil/folinic acid and oxaliplatin (Nordic FLOX), administered continuously or intermittently, in previously untreated metastatic colorectal cancer (mCRC). The influence of KRAS mutation status on treatment outcome was also investigated., Patients and Methods: Patients were randomly assigned to receive either standard Nordic FLOX (arm A), cetuximab and FLOX (arm B), or cetuximab combined with intermittent FLOX (arm C). Primary end point was progression-free survival (PFS). Overall survival (OS), response rate, R0 resection rate, and safety were secondary end points., Results: Of the 571 patients randomly assigned, 566 were evaluable in intention-to-treat (ITT) analyses. KRAS and BRAF mutation analyses were obtained in 498 (88%) and 457 patients (81%), respectively. KRAS mutations were present in 39% of the tumors; 12% of tumors had BRAF mutations. The presence of BRAF mutations was a strong negative prognostic factor. In the ITT population, median PFS was 7.9, 8.3, and 7.3 months for the three arms, respectively (not significantly different). OS was almost identical for the three groups (20.4, 19.7, 20.3 months, respectively), and confirmed response rates were 41%, 49%, and 47%, respectively. In patients with KRAS wild-type tumors, cetuximab did not provide any additional benefit compared with FLOX alone. In patients with KRAS mutations, no significant difference was detected, although a trend toward improved PFS was observed in arm B. The regimens were well tolerated., Conclusion: Cetuximab did not add significant benefit to the Nordic FLOX regimen in first-line treatment of mCRC.

Background: Preoperative radiotherapy for rectal cancer decreases local recurrence rates, but increases postoperative complications. Impaired postoperative leukocyte reaction after preoperative short-course radiotherapy has been reported. The aim was to assess postoperative morbidity and mortality in relation to leukocyte reaction and the time interval between radiotherapy and surgery., Materials and Methods: A retrospective analysis of patients included in the Stockholm I and II trials, randomising patients to surgery alone or to 5 x 5 Gy with immediate surgery, identified pre- and postoperative leukocyte values for 274 patients., Results: In the surgery alone group (n=144), all but three patients (2%) reacted with leukocytosis (ratio post/preoperative >1.0) on day 1 and all but 9 (6%) on day 5. In the radiotherapy group (n=130), 40 (31%) became leukopenic (<4 x 10(9) cells/L) after radiotherapy, 29 (22%) reacted abnormally (leukopenia or ratio < or =1.0) on day 1 and 66 (51%) on day 5 (all p<0.001). Preoperative leukocyte counts did not influence postoperative morbidity, but a poor response on day 1 increased the risk of sepsis (p<0.05) and mortality (6/29 (21%) vs. 6/101 (6%), p<0.05). An interval of 10 days or more between the start of radiotherapy and surgery also had an impact on mortality; 6/17 (35%) vs. 6/113 (5%), p=0.001. In a logistic regression analysis, the time interval and age were independent predictors of mortality., Conclusions: Impaired postoperative leukocyte reaction is frequent after short-course radiotherapy and increases the risk of postoperative complications and death. A longer than recommended radiotherapy-surgery interval also appears to be detrimental for postoperative death, independently of leukocyte response.

Purpose: This Nordic multicenter phase II study evaluated the efficacy and safety of oxaliplatin combined with the Nordic bolus schedule of fluorouracil (FU) and folinic acid (FA) as first-line treatment in metastatic colorectal cancer., Patients and Methods: Eighty-five patients were treated with oxaliplatin 85 mg/m(2) as a 2-hour infusion on day 1, followed by a 3-minute bolus injection with FU 500 mg/m(2) and, 30 minutes later, by a bolus injection with FA 60 mg/m(2) every second week. The same doses of FU and FA were also given on day 2., Results: Fifty-one of 82 assessable patients achieved a complete (n = 4) or partial (n = 47) response, leading to a response rate of 62% (95% CI, 52% to 72%). Nineteen patients showed stable disease, and 12 patients had progressive disease. Thirty-eight of the 51 responses were radiologically confirmed 8 weeks later (confirmed response rate, 46%; 95% CI, 36% to 58%). The estimated median time to progression was 7.0 months (95% CI, 6.3 to 7.7 months), and the median overall survival was 16.1 months (95% CI, 12.7 to 19.6 months) in the intent-to-treat population. Neutropenia was the main adverse event, with grade 3 to 4 toxicity in 58% of patients. Febrile neutropenia developed in seven patients. Nonhematologic toxicity consisted mainly of neuropathy (grade 3 in 11 patients and grade 2 in another 27 patients)., Conclusion: Oxaliplatin combined with the bolus Nordic schedule of FU+FA (Nordic FLOX) is a well-tolerated, effective, and feasible bolus schedule as first-line treatment of metastatic colorectal cancer that yields comparable results compared with more complex schedules.

A retrospective analysis of 99 patients treated at Radiumhemmet, Karolinska Hospital 1979-1990 with palliative radiotherapy for brain metastases from breast cancer was performed. A relief of symptoms was obtained in 45% of patients. Median time from diagnosis of breast cancer until CNS metastases was 33 months. Median survival time with CNS metastases after diagnosis was 5 months. Prognostic indicators for survival were studied. Patients operated for a singular brain metastasis and irradiated postoperatively had a mean survival of 21 months while patients with multiple brain metastases and meningeal spread displayed a short median survival. Extracranial disease status influenced prognosis significantly. Radiation dose (CRE) did not correlate with survival.

Ras proteins have been implicated in transducing cellular responses to DNA damaging agents. We used BZA-5B, an inhibitor of Ras-farnesylation, to examine the role of Ras in cellular sensitivity to cisplatin. A human melanoma cell line (224) with a Gln61Arg mutation in N-ras was used for these studies. We report that BZA-5B treated cells show an increased resistance to cisplatin. BZA-5B treatment decreased the number of cells showing in situ DNA fragmentation and increased cell viability and clonogenic survival after cisplatin treatment. Further experiments showed that cisplatin induction of the immediate early genes c-jun and p21cip1 was not affected by BZA-5B. Finally, we show that cisplatin causes only weak activation of Jun N-terminal kinase (JNK) in a human melanoma cell line. We conclude that inhibition of Ras function decreases the sensitivity of human melanoma cells to cisplatin-induced cell death.