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Introduction: Regorafenib is a multi-kinase inhibitor approved for patients with metastatic colorectal cancer (mCRC) who were previously treated with standard therapies. A few reports showed the impact of KRAS mutation on therapeutic efficacy of regorafenib. Only one study reported poor prognoses for patients treated with regorafenib who had large amounts of circulating cell-free DNA (cfDNA). In the present study, we evaluated the impact of KRAS mutations in tissue or plasma and amounts of cfDNA on prognoses of mCRC patients treated with regorafenib. Method: This is a biomarker investigation of the RECC study, which evaluated efficacy of regorafenib dose-escalation therapy. Plasma samples were obtained just before initiation of treatment with regorafenib. KRAS mutations were evaluated using tissue and plasma samples. cfDNA was extracted from plasma samples and quantified. Results: Forty-five patients were enrolled in this biomarker study. Median progression-free survival (PFS) and overall survival (OS) of patients without KRAS mutations in tissues were 1.9 months (95% confidence interval [CI] 1.7–2.0) and 8.9 months (95% CI: 6.5–11.2), and those of patients with KRAS mutations were 1.4 months (95% CI: 1.3–1.5) and 6.8 months (95% CI: 5.0–8.5). Median PFS and OS of patients with plasma KRAS mutations were 1.9 months (95% CI: 1.8–1.9) and 7.0 months (95% CI: 5.3–8.7), respectively. Median PFS and OS of patients without plasma KRAS mutations were 1.7 months (95% CI: 1.1–2.3) and 8.9 months (95% CI: 6.7–11.2), respectively. Prior to administration of regorafenib, KRAS mutations were detected in 6 of 16 (37.5%) patients who had no tissue KRAS mutations. Median OS of patients with high cfDNA concentration (>median) was significantly poorer than that of patients with low cfDNA. Conclusion: KRAS mutations in the tissue or plasma have no impact on efficacy of regorafenib. KRAS emerging mutations were observed in quite a few patients. Large amounts of cfDNA may indicate poorer prognoses for patients receiving late-line regorafenib chemotherapy.

Several studies have demonstrated that diverse systemic inflammatory-based prognostic parameters predict a poor prognosis in patients with gastric cancer. However, few studies have focused on the relationships between postoperative complications and systemic inflammatory-based prognostic parameters after curative gastrectomy. We investigated the relationships between postoperative complications and these parameters and assessed the clinical utility of the parameters as predictors of postoperative complications in patients with stage I–III gastric cancer. We retrospectively reviewed 300 patients who underwent curative gastrectomy for stage I–III gastric cancer. All postoperative complications were classified as infectious or noninfectious. We evaluated the relationships between postoperative complications and clinical factors, including systemic inflammatory-based prognostic parameters. In total, 101 patients (33.7%) had postoperative Clavien–Dindo grade II–IV complications, and 54 (18.0%) patients developed infectious complications including pancreatic fistula, pneumonia, anastomotic leak, intra-abdominal abscess, and cholecystitis. The relationships between postoperative complications and systemic inflammatory-based prognostic parameters were evaluated by the areas under the receiver operating characteristic curves. Postoperative pneumonia was identified as the most sensitive complication to the systemic inflammatory-based prognostic parameters. Multivariate analysis revealed that preoperative neutrophil-to-lymphocyte ratio (odds ratio, 14.621; 95% confidence interval, 1.160–184.348; p = 0.038) was an independent predictor of pneumonia. Preoperative neutrophil-to-lymphocyte ratio may be a useful predictor of postoperative pneumonia in patients with stage I–III gastric cancer after curative gastrectomy.

TAS-102 improves overall survival (OS) of patients with refractory colorectal cancer (CRC), resulting in median progression-free survival (PFS) of 2.0 months (RECOURSE trial). Subsequently, a combination of TAS-102 and bevacizumab was shown to extend median PFS by 3.7 months. However, approximately half of these patients experience grade 3/4 neutropenia. In this study, we evaluated whether biweekly TAS-102 and bevacizumab therapy has efficacy equal to that of conventional TAS-102 and bevacizumab therapy and whether it reduces adverse hematological effects.This phase II, investigator-initiated, open-label, single-arm, multicenter study was conducted in Japan. Eligible patients had previously received first- and second-line chemotherapy for metastatic CRC. TAS-102 (35 mg/m44 patients with metastatic colorectal cancer were enrolled in this study. Median PFS was 4.6 months (95% confidence interval [95% CI] 3.6-5.3) and median OS was 10.5 months (95% CI 9.6-11.4). A partial response was observed in 2 patients (4.5%, 95% CI 0.4-16.0%). The most common adverse event above grade 3 was neutropenia (7 patients, 15.9%, 95% CI 7.6-29.7%).Biweekly TAS-102 and bevacizumab therapy as third-line chemotherapy appears as effective as conventional TAS-102 and bevacizumab therapy, and this approach reduces adverse hematological effects.

TAS-102 improved the overall survival of metastatic colorectal cancer (CRC) patients with a median progression-free survival (PFS) in the RECOURSE trial. Subsequently, the combination of TAS-102 and bevacizumab was shown to extend the median PFS (C-TASK FORCE study). However, the study included patients who received second- and third-line treatment. Our study exclusively examined patients receiving this combination as a third-line treatment to investigate the clinical impact beyond cytotoxic doublets. This investigator-initiated, open-label, single-arm, multi-centered phase II study was conducted in Japan. Eligible CRC patients were refractory or intolerant to fluoropyrimidine, irinotecan, and oxaliplatin in first- and second-line therapy. TAS-102 (35 mg/m2) was given orally twice daily on days 1–5 and 8–12 in a 4-week cycle, and bevacizumab (5 mg/kg) was administered by intravenous infusion every 2 weeks. The primary endpoint was PFS and the secondary endpoints were time-to-treatment failure, response rate, overall survival (OS), and safety. Between June 2016 and August 2017, 32 patients were enrolled. All patients previously received bevacizumab. The median PFS was 4.5 months; the median overall survival was 9.3 months. Partial response was observed in two patients. The most common adverse events above grade 3 were neutropenia followed by thrombocytopenia. There were no non-hematological adverse events above grade 3 and no treatment-related deaths occurred. This study met its primary endpoint of PFS, which is comparable to the results of the C-TASK FORCE study. The TAS-102 and bevacizumab combination has the potential to be a therapeutic option for third-line treatment of metastatic CRC.

Anastomotic leak is one of the most serious postoperative complications, and intraoperative adequate perfusion plays a key role in preventing its development in gastric cancer surgery. This study aimed to investigate the relationships between anastomotic leak and the parameters defined by an assessment of intraoperative anastomotic perfusion using a near-infrared indocyanine green (ICG) fluorescence system and to evaluate the usefulness of this ICG fluorescence assessment in gastric cancer surgery. We retrospectively reviewed data of 100 patients who underwent gastric cancer surgery. In a visual assessment based on fluorescence intensity, we classified ICG fluorescence image patterns as homogeneous, heterogeneous, or faint. In a chronological assessment, the first or second time point of ICG fluorescence appearance on one or the other side of the anastomosis was defined as FT or ST, respectively. The time difference in ICG fluorescence appearance between FT and ST was defined as TD. The relationships between anastomotic leak and the evaluated clinical factors, including the parameters identified by the ICG fluorescence assessment, were evaluated using univariate or multivariate analysis. Although no signs of leak were found by surgeons’ subjective judgments, four patients developed postoperative anastomotic leak of Clavien–Dindo grade III or IV. Multivariate analysis revealed that TD was an independent predictor of anastomotic leak (odds ratio 35.361, 95% confidence interval 1.489–839.923, p = 0.027). A novel parameter identified using near-infrared ICG fluorescence assessment may be useful to predict anastomotic leak in gastric cancer surgery. UMIN Clinical Trials Registry: #UMIN000030747 ( https://www.umin.ac.jp/ctr/index.htm ).

Regorafenib significantly improves overall survival in previously treated metastatic colorectal cancer patients. However, various toxicities, such as hand-foot skin reaction (HFSR), fatigue, and liver dysfunction have limited the use of regorafenib. These toxicities appear soon after treatment initiation. The ReDOS study demonstrated the effectiveness of a weekly dose-escalation therapy of regorafenib starting with a lower daily dose; however, its usefulness in Asian subjects is unknown. We conducted a phase II study to evaluate the safety and survival benefit of regorafenib dose-escalation therapy for Japanese patients.Patients with sufficient organ function, who had previously received more than two lines of chemotherapy were included. Regorafenib was started at 80 mg/day and escalated to 120 mg/day in Week 2 and 160 mg/day in Week 3, if no severe drug-related toxicities were observed. The primary endpoint was cancer progression-free survival (PFS). Tumor response and progression were assessed radiologically every 8 weeks. This study was registered in the University Hospital Medical Information Network (UMIN#UMIN000028933).57 patients were enrolled and all started regorafenib at 80 mg/day. 32 patients (56.1%) were subsequently escalated to 120 mg/day and 19 (33.3%) to 160 mg/day. Only 8 patients (14.0%) discontinued treatment because of adverse events. Median PFS was 1.9 months. Median overall survival was 8.9 months, the response rate was 0%, and the disease control rate was 31.6%. The most frequent adverse event greater than grade 3 was hypertension (19.3%), followed by HFSR (14.0%).Regorafenib dose-escalation therapy is well tolerated with PFS-like regorafenib standard therapy.

Background: Several studies have demonstrated that diverse systemic inflammatory-based prognostic parameters predict poor prognosis in patients with gastric cancer. However, few studies focused on the relationships between postoperative complications and systemic inflammatory-based prognostic parameters after curative gastrectomy. We investigated the relationships between postoperative complications and these parameters to identify parameter-specific postoperative complications, and assessed the clinical utility of the parameters as predictors of postoperative complications in stage I–III gastric cancer patients.Methods: We retrospectively reviewed 300 patients who underwent curative gastrectomy for stage I–III gastric cancer. A postoperative complication sensitive to the systemic inflammatory-based prognostic parameters was identified using a receiver operating characteristic curve, and we evaluated the relationships between the identified postoperative complication and other clinical factors.Results: In total, 101 patients (33.7%) had postoperative Clavien–Dindo grade II–IV complications, namely anastomotic complications, such as leak, stenosis, or hemorrhage (35 patients, 11.7%); pancreatic fistula (16 patients, 5.3%); and pneumonia (14 patients, 4.7%). Postoperative pneumonia had the most sensitive relationship to five systemic inflammatory-based prognostic parameters, and was associated with poor prognosis in stage I–III gastric cancer patients after curative gastrectomy. Multivariate analysis revealed that preoperative neutrophil-to-lymphocyte ratio (odds ratio: 5.228, 95% confidence interval: 1.269–21.541; P=0.022) was an independent predictor of postoperative pneumonia.Conclusions: Preoperative neutrophil-to-lymphocyte ratio may be a useful predictor of postoperative pneumonia in stage I–III gastric cancer patients after curative gastrectomy.

The aim of this phase II study was to evaluate the efficacy and safety of combination therapy with five-cycle CAPOX (capecitabine plus oxaliplatin) plus bevacizumab, followed by five-cycle maintenance therapy with capecitabine plus bevacizumab and reintroduction of CAPOX plus bevacizumab for five cycles, with a preplanned intermittent oxaliplatin strategy in metastatic colorectal cancer (mCRC). Patients with untreated mCRC were administered CAPOX (130 mg/m2 oxaliplatin on day 1, 2000 mg/m2/day capecitabine on days 1–14, every 21 days) + bevacizumab (7.5 mg/kg) every 3 weeks for five cycles, maintenance treatment without oxaliplatin for five cycles, and CAPOX + bevacizumab reintroduction for five cycles or upon tumor progression. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were the time to treatment failure (TTF), overall survival, response rate (RR), and safety. Forty-seven patients who fulfilled the inclusion criteria were enrolled in the evaluation of efficacy and safety. Median PFS was 14.1 months (95% confidence interval [CI], 8.6–19.5), and median TTF was 12.3 months (95% CI, 10.3–14.3). The objective RRs were 51.1% (24/47) during induction therapy, 58.3% (21/36) during maintenance therapy, and 63.6% (14/22) during reintroduction therapy. The frequency of patients with neutropenia, diarrhea, peripheral sensory neuropathy, venous thromboembolism, or grade ≥ 3 allergic reactions was 2.1%. CAPOX plus bevacizumab therapy with a preplanned intermittent oxaliplatin strategy consisting of brief five-cycle induction therapy, five-cycle maintenance therapy with capecitabine plus bevacizumab, and five-cycle reintroduction therapy consisting of CAPOX plus bevacizumab is safe and effective for mCRC patients. UMIN ID: 000,005,732, date of registration: June 7, 2011. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000006695

We herein describe a case of laparoscopic surgery for an esophageal duplication cyst using a near‐infrared indocyanine green fluorescence system. A 64‐year‐old woman with a cystic tumor adjacent to the esophagogastric junction was referred to our hospital for treatment. Esophagogastroduodenoscopy and abdominal CT revealed a 70‐mm submucosal tumor derived from the abdominal esophagus. We performed laparoscopic resection and then evaluated the tissue perfusion of the abdominal esophagus by using a near‐infrared indocyanine green fluorescence system. A Dor fundoplication was performed to prevent postoperative gastroesophageal reflux disease and reinforce the mucosal layer defect. The postoperative course was uneventful, and pathological evaluation confirmed that the tumor was an esophageal duplication cyst. The patient did not develop recurrence in the 24 months after surgery. We have demonstrated that laparoscopic resection of an esophageal duplication cyst may be performed effectively with intraoperative assessment of tissue perfusion using a near‐infrared indocyanine green fluorescence system.

Approximately 30% patients with stage III colon cancer (CC) develop local recurrence and/or distant metastasis, even if postoperative adjuvant chemotherapy with oxaliplatin plus 5-fluorouracil and leucovorin (5-FU/LV) has been completed. In the present study, molecular analysis was performed to identify molecular markers of tumor recurrence in patients with stage III CC receiving oxaliplatin-based adjuvant chemotherapy. The FACOS study was conducted as a phase II study to evaluate the safety and efficacy of oxaliplatin-based treatment for stage III CC patients. Of the 132 CC patients enrolled in the present study, gene expression analysis using a microarray was conducted in 51 patients. Of these 51 patients, 6 developed recurrence within 5 years. The topmost 5% genes that showed differential expressions between cases that developed/did not develop recurrence were selected, and a set of predictive molecular markers for recurrence was identified. Of the 34,694 genes in the microarray, 1,734 genes were extracted as topmost 5% genes showing differential expressions between cases with and without recurrence. Among these, 10 genes, includingADH1A, ADH1C, CA12, CHP2, HMGCS2, SNAR-A1, TPI1, MS4A12, PLA2G10 and PTPRO, were identified as markers that could clearly divide patients with and without recurrence. Although several prediction models of tumor recurrence have been reported for CC, the set of 10 genes that the present study identified may be useful to predict the risk of recurrence in stage III CC patients receiving oxaliplatin-based adjuvant chemotherapy. Based on these results, high-risk patients with CC should be carefully observed to detect tumor recurrence during the follow-up period.

Low anterior resection syndrome (LARS) commonly develops after an anal sphincter-preserving operation (SPO). The etiology of LARS is not well understood, as the anatomical components and physiological function of normal defecation, which may be damaged during the SPO, are not well established. SPOs may damage components of the anal canal (such as the internal anal sphincter, longitudinal conjoint muscle, or hiatal ligament), either mechanically or via injury to the nerves that supply these organs. The function of the rectum is substantially impaired by resection of the rectum, division of the rectococcygeus muscle, and/or injury of the nervous supply. When the remnant rectum is small and does not function properly, an important functional role may be played by the neorectum, which is usually constructed from the left side of the colon. Hypermotility of the remnant colon may affect the manifestation of urge fecal incontinence. To develop an SPO that minimizes the risk of LARS, the anatomy and physiology of the structures involved in normal defecation need to be understood better. LARS is managed similarly to fecal incontinence. In particular, management should focus on reducing colonic motility when urge fecal incontinence is the dominant symptom.

Background: In the first-line treatment of metastatic colorectal cancer (mCRC) patients with CAPOX plus bevacizumab, the optimal duration of maintenance treatment without oxaliplatin to avoid discontinuation of therapy due to peripheral sensory neuropathy (PSN) remains unknown. The aim of this phase II study was to evaluate the efficacy and safety of combination therapy with five-cycle CAPOX (capecitabine plus oxaliplatin) plus bevacizumab, followed by five-cycle maintenance therapy with capecitabine plus bevacizumab and reintroduction of CAPOX plus bevacizumab for five cycles, with a preplanned oxaliplatin intermittent strategy in mCRC.Methods: Patients with untreated mCRC were administered CAPOX [oxaliplatin 130 mg/m2 and capecitabine (2000 mg/m2 daily) as intermittent treatment for 14 days, followed by a 7-day treatment-free interval, every 3 weeks] + bevacizumab (7.5 mg/kg) every 3 weeks for five cycles, maintenance treatment without oxaliplatin for five cycles, and CAPOX + bevacizumab reintroduction for five cycles or upon tumor progression. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were the time to treatment failure (TTF), overall survival, response rate (RR), and safety.Results: Forty-seven patients who fulfilled the inclusion criteria were enrolled in the evaluation of efficacy and safety. The relative dose intensity and the cumulative dose of oxaliplatin during the overall treatment period were 649.1 mg/m2 and 1132.5 mg, respectively. Median PFS was 14.1 months (95% confidence interval [CI], 8.6–19.5), and median TTF was 12.3 months (95% CI, 10.3–14.3). The objective RRs were 51.1% (24/47) during induction therapy, 58.3% (21/36) during maintenance therapy, and 63.6% (14/22) during reintroduction therapy. The frequency of patients with neutropenia, diarrhea, PSN, venous thromboembolism, or grade ≥ 3 allergic reactions was 2.1%.Conclusion: CAPOX plus bevacizumab therapy with a preplanned intermittent oxaliplatin strategy consisting of brief five-cycle induction therapy, five-cycle maintenance therapy with capecitabine plus bevacizumab, and five-cycle reintroduction therapy consisting of CAPOX plus bevacizumab is safe and effective for mCRC patients.Trial registration: This trial was registered with the University Hospital Medical Information Network on 7 June 2011 (UMIN ID: 000005732).

This randomized phase II trial compared tegafur–uracil/leucovorin (UFT/LV) plus oxaliplatin (TEGAFOX) to UFT/LV as adjuvant chemotherapy for patients with high-risk stage II/III colorectal cancer. From 2010 to April 2015, 159 patients who underwent curative resection were randomly assigned to receive TEGAFOX (85 mg/m2 oxaliplatin on days 1 and 15, 300 mg/m2/day UFT and 75 mg/day LV on days 1–28, every 35 days for five cycles) or UFT/LV. The primary study endpoint was disease-free survival. The 3-year disease-free survival rate was 84.2% in the TEGAFOX arm, versus 62.1% for UFT/LV. The stratified hazard ratio for disease-free survival for TEGAFOX compared to UFT/LV was 0.338 (P < 0.01). The incidence of any-grade adverse events was significantly higher in the TEGAFOX arm (96.1%) than in the UFT/LV arm (76.6%; P < 0.01). The rates of any-grade neutropenia, thrombocytopenia, aspartate aminotransferase/alanine aminotransferase elevation, and peripheral sensory neuropathy were higher in the TEGAFOX group, whereas the incidence of grade ≥ 3 adverse events did not differ between the groups. TEGAFOX is an additional adjuvant chemotherapy option for high-risk stage II/III colorectal cancer. UMIN ID: 000007696, date of registration: April 10, 2012

This randomized phase II trial compared tegafur-uracil/leucovorin (UFT/LV) plus oxaliplatin (TEGAFOX) to UFT/LV as adjuvant chemotherapy for patients with high-risk stage II/III colorectal cancer.From 2010 to April 2015, 159 patients who underwent curative resection were randomly assigned to receive TEGAFOX (85 mg/mThe 3-year disease-free survival rate was 84.2% in the TEGAFOX arm, versus 62.1% for UFT/LV. The stratified hazard ratio for disease-free survival for TEGAFOX compared to UFT/LV was 0.338 (P0.01). The incidence of any-grade adverse events was significantly higher in the TEGAFOX arm (96.1%) than in the UFT/LV arm (76.6%; P0.01). The rates of any-grade neutropenia, thrombocytopenia, aspartate aminotransferase/alanine aminotransferase elevation, and peripheral sensory neuropathy were higher in the TEGAFOX group, whereas the incidence of grade ≥ 3 adverse events did not differ between the groups.TEGAFOX is an additional adjuvant chemotherapy option for high-risk stage II/III colorectal cancer.UMIN ID: 000007696, date of registration: April 10, 2012.

Chemotherapy with oxaliplatin is known to induce sinusoidal obstruction syndrome (SOS). In a previous single-center study, we reported that oxaliplatin-induced increase in splenic volume (SV) is strongly indicative of SOS, and that this increase in SV persisted for 1 year after completing chemotherapy. The aim of this study was to confirm the oxaliplatin-induced SV change in a multicenter study in patients with stage III colon cancer in Japan.We enrolled 59 patients who underwent curative resection for stage III colon cancer in the FACOS study in a phase II multi-center clinical study. Participants received mFOLFOX6 or CAPOX as adjuvant chemotherapy. SV change was assessed three times by computed tomographic volumetry: before surgery, on completion of adjuvant chemotherapy, and 1 year after completing adjuvant chemotherapy.SV on completing and 1 year after chemotherapy was significantly higher than that before surgery (P 0.001). Oxaliplatin-induced SOS persisted for 1 year after the completion of adjuvant chemotherapy in half of the patients. There was no difference in 3-year disease-free survival with respect to the presence or absence of increased SV. An increase in SV was observed in 72% of patients treated with mFOLFOX6 and 94% of patients treated with CAPOX (P = 0.13).This study can be verified the findings observed in our previous single-center study, oxaliplatin-based adjuvant chemotherapy was associated with an increase in SV. Furthermore, this increase can persist for 1 year. The continuous presence of SOS may have a negative impact on prognosis in patients that develop recurrent disease.

Laparoscopic transverse colectomy is technically difficult. In mini-laparotomy surgery, colectomy for midtransverse colon cancer can easily be performed, but exact D2 lymph node dissection is very difficult for a variety of vessels in the transverse colon. Using 3D-CT imaging, we present a case of D2 lymph node dissection where mini-laparotomy transverse colectomy was performedby a small incision similar to that usedin laparoscopic surgery.The patient was a 60-yearoldwoman with early transverse colon cancer, which was locatedin the mid-transverse colon. Surgical treatment was plannedfor pT1b(1.5mm)andpVM1 in pathological findings after EMR. Using CT colonography(CTC), the location of the primary tumor was identified. Using simulation CTC(sCTC), composedof CTC and 3D imaging of the arteries andveins, the dominant artery was identified and D2 lymph node dissection was simulated. In addition, body surface 3D imaging and permeable surface 3D imaging of the abdominal trunk were performed. Using body surface 3D-sCTC, composedof sCTC and body surface 3D imaging, the minimum incision to enable D2 lymph node dissection was simulated.Using sCTC, it was identified that the dominant artery was the right branch of the middle colic artery(MCA Rt)andthe accompanying vein was branchedfrom the gastrocolic trunk(GCT). D2 lymph node dissection to separate the branching root of MCA Rt and the accompanying vein was simulated. Next, surgical incision was simulated using body surface 3D-sCTC. Because the branching roots of MCA Rt andGCT were locatedabout 5 cm cranial from the upper rim of the navel, a 7 cm upper abdominal midline incision was designed in addition to a 2 cm umbilical incision. Mini-laparotomy transverse colectomy with a 7 cm incision was performedin accordance with the simulation. The operation time was 2 hours and5 1 minutes, andbloodloss was due to occult bleeding. The patient was discharged 7 days after surgery without complications, and the final diagnosis was pT1bN0M0, StageⅠwith no recurrence for 4 years and2 months after surgery. The cranial incision from the upper rim of the navel has shrank about 3 cm, and the umbilical incision is not noticeable.D2 lymph node dissection of minilaparotomy transverse colectomy can be a treatment option for early transverse colon cancer through using body surface 3DsCTC.

Adjuvant chemotherapy with oxaliplatin combined with a fluoropyrimidine derivative is widely accepted as standard therapy for patients with stage III colon cancer, since few clinical data are available for Japanese patients. The FACOS trial investigated the tolerability of modified FOLFOX6 (mFOLFOX6) and XELOX regimens in Japanese colon cancer patients. Twelve cycles of mFOLFOX6 or 8 cycles of XELOX were given to patients with eligibility: stage III curatively resected colon cancer, performance status of 0–1, age from 20 to 75 years, and adequate organ function. The primary endpoint was 3-year disease-free survival. Secondary endpoints were the incidence of adverse events (AEs) and the completion rate of study therapy. From April 2010 to April 2014, a total of 132 patients were enrolled. Safety was analyzed in 130 patients, with finalized data from 73 patients receiving mFOLFOX6 and 57 patients receiving XELOX. A total of 130 patients (100%) experienced AEs (any grade), and 52 patients (40.0%) experienced AEs of grade ≥ 3. No significant difference in the frequency of grade ≥ 3 AEs was observed between mFOLFOX6 and XELOX groups. Continuation of the planned cycle rate of protocol treatment was 69.9% in the mFOLFOX6 group and 68.4% in the XELOX group. Treatment was discontinued because of AEs in 14 patients (19.2%) in the mFOLFOX6 group and 8 (14.0%) in the XELOX group. Mean relative dose intensity for oxaliplatin was 78.0% in the mFOLFOX6 group and 82.8% in the XELOX group. As adjuvant chemotherapy for stage III colon cancer, mFOLFOX6/XELOX regimens are acceptable.

Diverticular disease of the colon occurs quite frequently in developed countries, and its prevalence has recently increased in Japan. The appearance of diverticulosis increases with age, although mostly remaining asymptomatic. Approximately 20% of cases require treatment. As the Western lifestyle and number of elderly people increase, the need for medical treatment also increases. Computed tomography (CT) is the gold standard for diagnosing diverticulitis. Complicated diverticulitis is classified by the size and range of abscess formation and the severity of the peritonitis. Each case should be classified based on clinical and computed tomography (CT) findings and then treated appropriately. Most patients with uncomplicated diverticulitis (stages 0–Ia) can be treated conservatively. Diverticulitis with a localized abscess (stages Ib–II) is generally resolved with conservative treatment. If the abscess is larger or conservative treatment fails, however, percutaneous drainage or surgery should be considered. Operative treatment is considered standard therapy for severe diverticulitis with perforation and generalized peritonitis (stages III–IV). Colonic diverticulitis treated conservatively frequently recurs. Elective surgery after recovery should be considered carefully and decisions made on a case‐by‐case basis. Because cases of colonic diverticulitis will undoubtedly increase in Japan, it is likely that we will be confronted with increasing numbers of treatment decisions. We therefore need to have a systematic strategy for treating the various stages of colonic diverticulitis appropriately. We herein review the management of complicated diverticulitis.

It is reported that simulation computed tomography colonography(S-CTC), which combines CTC and 3-dimensional(3D)vascular imaging, is useful in colorectal cancer surgery. However, it is difficult to create 3D vascular images using non-contrast CT. Laparoscopic transverse colectomy is said to be technically difficult. Mini-laparotomy surgery for mid-transverse colon cancer is quite easy to perform. However, exact D2 lymph node dissection is very difficult. We present a case of D2 lymph node dissection during mini-laparotomy transverse colectomy performed using S-CTC, which involves the creation of 3D vascular images using non-contrast CT.The patient was a 77-year-old man with transverse colon cancer located in the mid-transverse colon, cT2N0M0, Stage Ⅰ. He had coexisting chronic renal failure. Non-contrast CT was performed prior to surgery, and the images were processed using workstation Zaiostation2.Both the artery and the vein created from non-contrast CT could be visualized clearly until the marginal vessels. Using noncontrast S-CTC in combination with CTC and 3D artery imaging, it was identified that the dominant artery was the left branch of the middle colic artery(MCA Lt), while the right branch of the MCA(MCA Rt)and accessory MCA(AMCA)were 10 cm or more apart. The fusion of 3D artery and vein imaging made it evident that the vein accompanying MCA Lt branched from the superior mesenteric vein. Using non-contrast S-CTC, D2 lymph node dissection, dissection of the branching root of MCA Lt and the vein at the same level was simulated. Thus, mini-laparotomy transverse colectomy was performed through a 7 cm incision, in accordance with the simulation.Non-contrast S-CTC was useful for performing D2 lymph node dissection during mini-laparotomy transverse colectomy.

The aim of this study was to assess the impact of partial gastrectomy on postoperative outcomes in elderly patients with gastric cancer. Sixty -three consecutive elderly patients aged 75 years and older with histologically proven Stage ⅠA gastric adenocarcinoma who underwent partial gastrectomy(PG, n=7)or normal gastrectomy(NG, n=56)were investigated. PG was performed by segmental gastrectomy or local gastrectomy due to poor performance status, severe comorbidities, and social background instead of normal gastrectomy(distal, proximal, and total gastrectomy). Both body mass index(BMI)and body weight changes 12 months postoperatively were significantly higher in those who underwent PG(20.5 kg/m2 vs 18.4 kg/m2, p=0.043; and 96.6% vs 86.4%, p=0.016)despite being statistically similar preoperatively. The 5-year cause-specific survival rate of those who underwent PG was 100% excluding relapse cases. The 5-year overall survival rates were 86% in those who underwent PG and 67%in those who underwent NG, although they differed significantly. Partial gastrectomy may be a valid surgical procedure that may yield better prognosis compared to that with normal gastrectomy for elderly patients with Stage ⅠA gastric cancer.

Perfusion computed tomography (PCT) is a less invasive imaging modality that provides information about tissue hemodynamics at the capillary level. The present study aimed to investigate the correlation between hepatic perfusion and gastric cancer progression. A total of 136 patients with gastric adenocarcinoma were evaluated in the present study. Prior to initial treatment, liver PCT was performed across the hepatic hilar plane and the hepatic blood flow (HBF) was measured using the dual-input deconvolution method. HBF was compared with clinicopathological factors, patient prognosis and circulating serum proangiogenic cytokines. The median HBF was 217 ml/min/100 g tissue. Patients with high HBF had larger tumors (43 mm vs. 71, P

Background The neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) are associated with poor prognoses in patients with gastric cancer; however, few studies have focused on the dynamic changes in these ratios during the treatment of patients with gastric cancer. Here, we assessed the clinical utility of changes in these ratios as prognostic indicators in patients with stage II or III gastric cancer who received adjuvant chemotherapy. Methods We retrospectively reviewed 100 patients who received S-1 adjuvant chemotherapy at ≥70% of the relative dose intensity, and their NLRs and PLRs were evaluated at different times: prior to gastrectomy and upon commencement and termination of adjuvant chemotherapy. To assure the clinical utility of the changes in NLR and PLR as prognostic indicators, other clinical factors were assessed as well. Results Disease recurred in 35 patients as follows: lymph node metastasis (17 patients, 17.0%), peritoneal metastasis (12 patients, 12.0%), and hematogenous metastasis (6 patients, 6.0%); 24 patients died. An increase in the NLR during adjuvant chemotherapy with S-1 was identified as an independent indicator associated with overall survival (hazard ratio [HR] 6.736, 95% confidence interval [CI] 2.420–18.748; P

224 Background: The combination regimen of TAS-102 and bevacizumab as salvage-line therapy for metastatic colorectal cancer (mCRC) was established based on its high clinical effectiveness (C-TASK FORCE). Recently, our current phase II TAS-CC3 study demonstrated comparable median progression-free survival (PFS: 4.5m) and overall survival (OS: 9.2m) with exclusive inclusion of 3rd line therapy patients. However, practical predictors for its efficacy are lacking. This study evaluated inflammation-based scores as potential predictors for this combination therapy. Methods: This is a post hoc analysis of investigator-initiated, open-label, single-arm, multicentered phase II study (TAS-CC3) in Japan with 32 mCRC patients treated with the combination therapy. We investigated the predictive and prognostic values of pretreatment blood inflammation-based scores, including neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), and lymphocyte-monocyte ratios (LMR), on disease-control (DC), PFS and OS. These were divided into two groups (high and low) using cut-off of each median values. This study was registered at the University Hospital Medical Information Network, as UMIN#000022438. Results: ROC curve analyses of 3 inflammation-based scores versus DC showed a best predictive performance in LMR, followed by NLR and PLR (AUC: 0.89, 0.85, and 0.68, respectively). The high LMR group had a significantly higher DC rate than the low group (87.5 vs. 43.8%, P= 0.023). Two patients showing partial responses were in the high group. The high LMR group showed significantly longer survivals compared with the low group (4.9 vs. 2.3m, respectively for median PFS, P= 0.014) (20.5 vs. 5.1m, respectively for median OS, P< 0.001). The values of LMR were significantly correlated with PFS and OS (r = 0.56: P< 0.001 and 0.62: P< 0.001, respectively). Conclusions: Pretreatment LMR is a valid predictive and prognostic biomarker for mCRC patients with TAS-102 and bevacizumab treatment and might be clinically useful for selecting patients of the responder. Clinical trial information: 000022438.

116 Background: Regorafenib, a multi-kinase inhibitor, significantly improved overall survival in previously treated metastatic colorectal cancer (mCRC) patients in the phase 3 CORRECT trial. Despite its significant benefits, various toxicities such as hand-foot skin reaction (HFSR), fatigue, and liver dysfunction have limited regorafenib use. The toxicities occur soon after treatment initiation, typically within the first cycle, and later improve. Although the standard daily dose of regorafenib is 160 mg, physicians have adopted various dosing regimens in clinical practice, indicating the need to optimize the dosing strategy to maintain the antitumor benefits. The ReDOS study demonstrated the effectiveness of a weekly dose-escalating strategy (WDES) of regorafenib starting with a lower daily dose. We conducted the phase II RECC study to evaluate the safety and efficacy of WDES for regorafenib in an Asian population. Methods: Patients with sufficient organ function who had previously received more than two lines of chemotherapy were included. Regorafenib was started at 80 mg/day and escalated to 120 mg/day in Week 2 and 160 mg/day in Week 3 if no severe drug-related toxicities were observed. The primary endpoint was progression-free survival (PFS) and secondary endpoints were time to treatment failure (TTF), response rate (RR), overall survival (OS), and safety. Tumor response and progression were assessed radiologically every 8 weeks. Results: From March 2017 to November 2018, 57 eligible patients were enrolled and all started regorafenib at 80 mg/day. Thirty-five patients (61%) were subsequently escalated to 120 mg/day and 16 (28%) to 160 mg/day. Forty patients (70.2%) finished Cycle 2 at 8 weeks. Only 8 patients (14%) discontinued treatment because of adverse events. The median PFS was 1.9 months, RR was 0%, and disease control rate was 32%. The most frequent adverse event ≥grade 3 was hypertension (17.5%), followed by HFSR (14%). No treatment-related deaths occurred. Conclusions: Regorafenib dose escalation was well tolerated with PFS similar to that reported in the CORRECT study, indicating that WDES may represent an option for regorafenib administration. Clinical trial information: UMIN000028933.

We report a case of rectal metastasis from breast cancer.Colorectal metastasis from breast cancer is sometimes difficult to diagnose before surgery.A transanal needle biopsy was thought to be useful for a diagnosis and selection of treatment method.

The aim of this single-arm phase II clinical trial was to evaluate whether the alternate-day administration of S-1 plus irinotecan would reduce the incidence of severe diarrhea in comparison to consecutive-day S-1 administration (standard IRIS regimen) in second-line treatment for patients with metastatic colorectal cancer. Patients with metastatic colorectal cancer after failure with first-line treatment of oxaliplatin and fluoropyrimidine were enrolled. Irinotecan (150 mg/m2) and bevacizumab (5 mg/kg) were given intravenously on day 1. Oral S-1 was administered on alternate days at a dose of 40–60 mg twice a day. Cycles were repeated every 2 weeks. The primary endpoint was the incidence of grade ≥ 3 diarrhea. Our hypothesis set 21% as a threshold incidence and 10% as an expected incidence from previous studies with one-sided alpha 0.05. The secondary endpoints included the relative dose intensity, progression-free survival, overall survival and other adverse events. A total of 51 patients were enrolled. The incidence of grade ≥ 3 diarrhea was 15.7% (8/51). Other common grade ≥ 3 adverse events were neutropenia, anemia, thrombocytopenia and fatigue were 13.7% (7/51), 5.9% (3/51), 2.0% (1/51) and 5.9% (3/51), respectively. The relative dose intensities of irinotecan, bevacizumab, and S-1 were 80.0, 86.8, and 77.7%, respectively. The median progression-free survival and overall survival were 8.4 months (5.8–9.8) and 17.1 months (11.8–22.3). The alternate-day S-1 administration does not have significant effectiveness to reduce diarrhea in patients who received second-line treatment for metastatic colorectal cancer.

The clinical outcomes of patients who have undergone total pelvic exenteration (TPE) for locally advanced primary colorectal cancer have not been satisfactory. For the last 13 years, we have performed layer-oriented, en bloc resection of tumor for which TPE is indicated, in the hope of improving postoperative outcomes. The clinical outcomes of these cases were retrospectively analyzed.A total of 54 patients who underwent TPE from 1986 to 2013 were retrospectively analyzed. Since 2002, a layer-oriented removal for clinical T4 colorectal cancer, as in T3 or less invasive tumors removed by total mesorectal excision, was applied to 23 cases for which TPE was indicated. Postoperative mortality, morbidity, overall survival (OS), and disease-free survival (DFS) were evaluated.On univariate analysis, good postoperative OS and DFS were associated with the layer-oriented operative maneuver, blood loss less than 2000 mL, negative nodal metastasis, and no preoperative radiation therapy. Male sex was the marginal determinant correlated with good OS and DFS. Depth of invasion to T3 was the marginal determinant correlated with good DFS. On multivariate analysis using the 4 factors identified on univariate analyses, the layer-oriented operative procedure was a significant determinant for both good OS and DFS, together with negative nodal metastases. Postoperative mortality and morbidity in the layer-oriented excision were acceptable.For primary colorectal cancers for which TPE is indicated, layer-oriented excision was a safe and effective procedure, and it may be recommended as one of the standard surgical approaches in TPE.

Ryohei Itagaki, Keiji Koda, Masato Yamazaki, Kiyohiko Shuto, Chihiro Kosugi, Atsushi Hirano, Hidehito Arimitsu, Risa Shiragami, Yukino Yoshimura, Masato Suzuki Department of Surgery, Teikyo University Chiba Medical Center, Anesaki, Ichihara, Chiba, Japan Purpose: Serotonin (5-hydroxytryptamine [5-HT])3 receptor antagonists are effective for the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), in which exaggerated intestinal/colonic hypermotility is often observed. Recent studies have suggested that the motility disorder, especially spastic hypermotility, seen in the neorectum following sphincter-preserving operations for rectal cancer may be the basis of the postoperative defecatory malfunction seen in these patients. We investigated the efficacy of 5-HT3 receptor antagonists in patients suffering from severe low anterior resection syndrome. Patients and methods: A total of 25 male patients with complaints of uncontrollable urgency or fecal incontinence following sphincter-preserving operations were enrolled in this study. Defecatory status, assessed on the basis of incontinence score (0–20), urgency grade (0–3), and number of toilet visits per day, was evaluated using a questionnaire before and 1 month after the administration of the 5-HT3 antagonist ramosetron. Results: All the parameters assessed improved significantly after taking ramosetron for 1 month. The effect was more prominent in cases whose anastomotic line was lower, ie, inside the anal canal. Defecatory function was better in patients who commenced ramosetron therapy within 6 months postoperatively, as compared to those who were not prescribed ramosetron for more than 7 months postoperatively. Conclusion: These results suggest that 5-HT3 antagonists are effective for the treatment of low anterior resection syndrome, as in diarrhea-predominant irritable bowel syndrome. The improvement in symptoms is not merely time dependent, but it is related to treatment with 5-HT3 antagonists. Keywords: low anterior resection syndrome, serotonin receptor antagonist, ISR, defecatory malfunction

Postoperative anastomotic leaks and subsequent mediastinal abscess are serious complications. The purpose of this study was to assess the efficacy of naso-esophageal extraluminal drainage after thoracic esophagectomy with gastric conduit reconstruction using a posterior mediastinal route. About 50 of 365 patients (13.7%) with esophageal cancer and postoperative anastomotic leak after curative esophagectomy was investigated. Beginning in June 2009, naso-esophageal extraluminal drainage by inserting a naso-esophageal aspiration tube into the abscess cavity when percutaneous abscess drainage was introduced which was ineffective or technically impossible. Twenty-five patients underwent naso-esophageal extraluminal drainage concomitantly with enteral nutrition. Twenty-one (84%) patients had major leaks, one (4%) minor leak and three (12%) had endoscopically proven conduit necrosis. None of the naso-esophageal extraluminal drainage cases (100%) required reintervention or reoperation and all experienced complete cure (100%) during hospitalization. Endoscopic balloon dilatation was performed for four patients after discharge because of anastomotic stricture. Patients with leaks were divided into two groups: current group (n = 32), treated after June 2009, and preceding group (n = 18), treated prior to the introduction of naso-esophageal extraluminal drainage. Significantly more patients in the preceding group suffered respiratory failure (28% vs. 61%, p = 0.024), and higher reoperation rate (0% vs. 17%, p = 0.042) and hospital mortality (0% vs. 22%, p = 0.013). In the current group, 31 (97%) patients experienced complete cure during hospitalization. Naso-esophageal extraluminal drainage and concomitant enteral nutritional support are less invasive, and effective and powerful methods to treat even major leakage after esophagectomy. These methods may be an alternative management to improve mortality for patients with esophageal cancer.

Postoperative anastomotic leaks and subsequent mediastinal abscess are serious complications. The purpose of this study was to assess the efficacy of naso-esophageal extraluminal drainage after thoracic esophagectomy with gastric conduit reconstruction using a posterior mediastinal route. About 50 of 365 patients (13.7%) with esophageal cancer and postoperative anastomotic leak after curative esophagectomy was investigated. Beginning in June 2009, naso-esophageal extraluminal drainage by inserting a naso-esophageal aspiration tube into the abscess cavity when percutaneous abscess drainage was introduced which was ineffective or technically impossible. Twenty-five patients underwent naso-esophageal extraluminal drainage concomitantly with enteral nutrition. Twenty-one (84%) patients had major leaks, one (4%) minor leak and three (12%) had endoscopically proven conduit necrosis. None of the naso-esophageal extraluminal drainage cases (100%) required reintervention or reoperation and all experienced complete cure (100%) during hospitalization. Endoscopic balloon dilatation was performed for four patients after discharge because of anastomotic stricture. Patients with leaks were divided into two groups: current group (n = 32), treated after June 2009, and preceding group (n = 18), treated prior to the introduction of naso-esophageal extraluminal drainage. Significantly more patients in the preceding group suffered respiratory failure (28% vs. 61%, p = 0.024), and higher reoperation rate (0% vs. 17%, p = 0.042) and hospital mortality (0% vs. 22%, p = 0.013). In the current group, 31 (97%) patients experienced complete cure during hospitalization. Naso-esophageal extraluminal drainage and concomitant enteral nutritional support are less invasive, and effective and powerful methods to treat even major leakage after esophagectomy. These methods may be an alternative management to improve mortality for patients with esophageal cancer.

Background TAS-102 improved overall survival of metastatic colorectal cancer (mCRC) patients with median progression-free survival (PFS) of 2.0 months (RECOURSE trial). Subsequently, the combination of TAS-102 and bevacizumab (BV) has been shown to extend median PFS to 3.7 months (C-TASK FORCE). However, this study included patients with 2nd line and 3rd line chemotherapy. Furthermore, combination chemotherapy of TAS-102 plus BV was reportedly associated with grade ≥3 neutropenia in 72% of treated patients. This study was designed for patients being treated as 3rd line chemotherapy to investigate the clinical impact of this combination and whether neutropenia could be suppressed by altering the TAS-102 administration protocol (biweekly method). Methods This phase II study was conducted in investigator-initiated, open-label, single-arm, multicenter manner in Japan. Eligible patients were 20-80 years old and had to have an ECOG performance status of 0 or 1; had confirmed unresectable mCRC with histologically diagnosed adenocarcinoma; had previously administrated first- and second-line chemotherapy for mCRC and whose tumors were diagnosed as progression of disease (PD). TAS-102 (35 mg/ m²) was given orally twice daily on days 1 -5 and 15 -19 in a 4-weeks cycle, and BV (5 mg/ kg) was administered by intravenous infusion for 30 min in every 2 weeks. The primary endpoint was PFS, and the secondary endpoints were response rate (RR), disease control rate (DCR), overall survival (OS), and safety. This study was registered at the University Hospital Medical Information Network, as UMIN#000030030. Results Between January 1, 2018, and March 31, 2019, 45 patients with mCRC were enrolled in this study (median age, 63; male, 51%). The median PFS was 121 days. The RR and DCR were 4.4% and 73.3%, respectively. Grade 3 or higher adverse events were hypertension (20.0%), neutropenia (15.5 %), leukopenia (6.7 %), fatigue (6.7 %), anemia (4.4 %), anorexia (2.2 %), nausea (2.2 %), creatinine increased (2.2 %) and proteinuria (2.2 %). No treatment-related deaths occurred. Conclusions Biweekly administration of TAS-102 and BV prevents neutropenia and could be one of the treatment options for 3rd line chemotherapy for mCRC. Clinical trial identification UMIN000030030. 2018/March/01. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

614 Background: TAS-102 improved overall survival of metastatic colorectal cancer (mCRC) patients with median progression free survival (PFS) of 2.0 months (RECOURSE trial). Subsequently, the combination of TAS-102 and bevacizumab has been shown to extend median PFS with 3.7 months (C-TASK FORCE). However, this study included patients with 2nd line and 3rd line chemotherapy. Our study was planned exclusively for patients receiving this combination as a 3rd line chemotherapy to investigate clinical impact of this combination beyond cytotoxic doublet. Methods: This phase II study was conducted in investigator-initiated, open-label, single-arm, multicentered manner in Japan. Eligible patients were 20-80 years old, and had to have an ECOG performance status of 0 or 1; had confirmed unresectable mCRC with histologically diagnosed adenocarcinoma; were refractory or intolerant to fluoropyrimidine, irinotecan, and oxaliplatin in the 1st and the 2nd line chemotherapy. TAS-102 (35 mg/ m²) was given orally twice daily on days 1–5 and 8–12 in a 4-weeks cycle, and bevacizumab (5 mg/ kg) was administered by intravenous infusion for 30 minutes in every 2 weeks. The primary endpoint was progression free survival (PFS), and the secondary endpoints were time to treatment failure (TTF), response rate (RR), overall survival (OS), and safety. Results: Between June 2016 and August 2017, 32 pts were enrolled. The median PFS was 4.5 months, and the median OS was 9.3 months. Partial response was observed in 2 patients. The most common adverse events above grade 3 were neutropenia (15 patients) followed by thrombocytopenia (4 patients). Treatment-related serious adverse events were reported in 1 patient. There were no non-hematologic adverse events above grade 3. No treatment-related deaths occurred. Conclusions: This is the first study which involves the combination TAS-102 and bevacizumab as the 3rd line chemotherapy in the setting beyond cytotoxic doublet for the patients with mCRC. This study met its primary endpoint PFS, which is comparable to the results of C-TASK FORCE study. This combination has a potential to be one of therapeutic options of the 3rd line chemotherapy for mCRC. Clinical trial information: 000022438.

546 Background: Oxaliplatin reduces the recurrence rate after curative surgery for stage III colorectal cancer. However, it can cause hepatic sinusoidal obstruction syndrome (SOS), an adverse effect that creates morbidity after liver resection for recurrence. SOS has conventionally been diagnosed by liver biopsy, which is invasive. We have reported that a 10% increase in splenic volume (SV) indicates SOS (J Surg Oncol 2017). In this multi-center study, we measured SV to evaluate SOS caused by adjuvant chemotherapy. Methods: This multi-center study included the participants of the FACOS study, which included patients with Stage III colon cancer. Participants received 12 cycles of mFOLFOX6 or eight cycles of XELOX as adjuvant chemotherapy. We used multi-detector raw CT to measure SV three times; before surgery, on completion of adjuvant chemotherapy, and 1-year after completing adjuvant chemotherapy. CT images were taken in 5-mm slices. SV was calculated by using a volume calculator SYNAPSE VINCENT v3.0(Fujifilm, Japan). Results: The FACOS study included 130 patients, 16.9% of whom discontinued treatment. The mean relative dose intensity (RDI) of oxaliplatin was 80.3%. Grade 3 neutropenia, thrombocytopenia, and neuropathy were observed in 28.5%, 6.2%, and 4.6% of patients, respectively. The 3 year DFS was 82.2%. We analyzed data of 75 patients (57.7%) for whom the three CT studies were available. SV on completing chemotherapy (median 181 cm3) and SV 1-year after completing chemotherapy (141 cm3) were significantly higher than that before surgery (128 cm3) (P < 0.001). SV increased by more than 10% after chemotherapy in 72% and was still increased 1 year after chemotherapy in 51% of patients. Conclusions: In our previous single center study, SV had increased in 84% on completing chemotherapy and was still increased in 47% 1 year after completing chemotherapy. Adjuvant chemotherapy without oxaliplatin induced SV increases in only 20% of patients on completing chemotherapy. Thus, these results are reproducible and show the potential of oxaliplatin to induce SOS. Oxaliplatin frequently induces SOS and this SOS persists for over 1 year in half of affected patients. Clinical trial information: UMIN000005427.

Background: It has not been elucidated whether the clinical efficacy of oral fluoropyrimidines for adjuvant chemotherapy of colorectal cancer varies with tumor biological characteristics. Patients and Methods: A multicenter randomized trial was performed comparing oral tegafur/gimeracil/oteracil (S-1) and uracil-tegafur/ leucovorin (UFT/LV) as adjuvant therapy for stage III colorectal cancer. Postoperative survival was compared based on the 5-FU-related mRNA levels in cancer tissues. Results: Among patients with tumor expressing dihydropyrimidine dehydrogenase (DPD) mRNA within the 66.7th percentile (lower 2/3) of all cases, overall survival (OS) was significantly better in the S-1 than in the UFT/LV group. In the S-1 group, patients with low DPD-expressing tumors had significantly better OS than those with highly expressing tumors. Patients with low thymidine synthase (TS)-expressing tumors had significantly better OS than those with highly expressing tumors. Conclusion: The efficacy of oral fluoropyrimidines as adjuvant chemotherapy for colorectal cancer may be influenced by the level of 5-FU-related mRNA in cancer tissues.

The efficacy and safety of neoadjuvant chemotherapy in patients with highly advanced rectal cancer for whom radical surgery was considered difficult were evaluated.From June 2007 to February 2011, 10 advanced lower rectal cancer patients with factors contraindicative of curative surgery with total mesenteric excision were eligible for this study. Neoadjuvant chemotherapy consisting of modified OPTIMOX1 (mFOLFOX6 and sLV5FU2 alternating administration) plus bevacizumab was administered.Adverse events seen with chemotherapy consisted of grade 2 leukopenia in 1 patient, but there were no cases of delayed administration or dosage reduction due to grade 2 neurotoxicity. The surgical procedures were anus-preserving resection in 8 patients, total pelvic exenteration in 1 patient, and posterior pelvic exenteration in 1 patient. A positive radial margin was confirmed in 3 patients, but radical surgery was performed, histologically as well, in the other patients. Upon comparing the clinical and postoperative histological stages, primary tumor and node downstaging was achieved in 20.0% and 70.0% of the patients, respectively.These findings suggest the potential utility of neoadjuvant chemotherapy consisting of modified OPTIMOX1 plus bevacizumab prior to permitting radical resection or anus-preserving surgery in patients with highly advanced rectal cancer.