Trial Protocol of a Phase II Study of mFOLFOXIRI after Metastasectomy in Patients with Oligometastatic Colorectal Cancer (FANTASTIC Study).

Background: The survival benefit of adjuvant chemotherapy after surgical resection of oligometastases from colorectal cancer (CRC) remains unclear. The prognostic role of circulating-tumor DNA (ctDNA) was reported recently and a risk stratification strategy based on monitoring minimal/molecular residual disease (MRD) has been proposed, however, which drug regimen is most effective for ctDNA-positive patients is unknown. Methods/Design: Oligometastatic CRC patients planning to undergo surgery were registered in this study. After metastasectomy, the registered patients were enrolled in the treatment arm, in which 8 courses of modified-FOLFOXIRI (mFOLFOXIRI; irinotecan 150 mg/m2, oxaliplatin 85 mg/m2, l-leucovorin (l-LV) 200 mg/m2, and 46-h continuous infusion of 5-fluorouracil (5-FU) 2400 mg/m2 every 2 weeks) followed by 4 courses of 5-FU/l-LV are administered. The patients who did not meet the eligibility criteria for the treatment arm or did not consent to mFOLFOXIRI enrolled in the observation arm in which standard of care treatment is provided. Prospective blood collections for retrospective ctDNA analysis are scheduled pre-surgery, and at 28 days, 4 and 7 months after surgery. The primary endpoint is treatment compliance at 8 courses of mFOLFOXIRI and the key secondary endpoints are the ctDNA-positivity rate and survival outcomes in ctDNA-positive and -negative groups. A total of 85 patients will be enrolled from 11 institutions. First patient-in was on July 2020. Accrual completed in February 2024. Discussion: This study will potentially identify a better treatment strategy for patients with resectable oligometastatic CRC having postsurgical ctDNA positivity, compared to the current standard of care approaches.

Colorectal Cancer Recurrence Prediction Using a Tissue-Free Epigenomic Minimal Residual Disease Assay.

PURPOSE: Post-treatment detection of circulating tumor DNA (ctDNA) is strongly predictive of recurrence. Most molecular residual disease (MRD) assays require prior tissue testing to guide ctDNA analysis, resulting in lengthy time to initial results and unevaluable patients. PATIENTS AND METHODS: We assessed a tissue-free assay (Guardant Reveal) that bioinformatically evaluates >20,000 epigenomic regions for ctDNA detection in 1,977 longitudinally collected post-operative plasma samples from 342 patients with resected colorectal cancer (CRC). RESULTS: We observed sensitive and specific detection of MRD associated with clinically meaningful differences in recurrence-free interval at each timepoint evaluated with a median lead time of 5.3 months. Longitudinal sensitivity in stage II or higher colon cancer was 81%. Sensitivity increased with serial measurement and varied by recurrence site: higher for liver (100%) versus lung (53%) and peritoneal (40%). Sensitivity among rectal cancer patients was 60% owing to a high proportion of lung metastases. Specificity was 98.2% among 1,461 post-treatment samples (99.1% among those with follow-up longer than the upper interquartile range of the lead time observed in this study). CONCLUSIONS: Our data demonstrate the potential clinical utility of ctDNA as a tool to improve management of stage II and higher CRC with a methodology that is non-invasive, accessible, and allows for rapid evaluation to inform clinical decisions.

Long-term Outcome After Surgical Resection of Paraaortic Lymph Node Metastasis of Colorectal Cancer: A Multicenter Retrospective Study.

BACKGROUND: The significance of resection of paraaortic lymph node metastasis in colorectal cancer is controversial. OBJECTIVE: To clarify the prognosis of colorectal cancer after paraaortic lymph node metastasis resection. DESIGN: Multicenter retrospective study. SETTINGS: Thirty-six institutions in Japan participated in this study. PATIENTS: Patients with resected and pathologically proven paraaortic lymph node metastasis of CRC between 2010 and 2015. DATA SOURCES: Database and medical records at each institution. MAIN OUTCOME MEASURES: Overall survival after paraaortic lymph node metastasis resection, recurrence-free survival, and recurrence patterns after R0 resection of paraaortic lymph node metastasis. RESULTS: A total of 133 patients were included in the primary analysis population in this study. The 5-year overall survival rate (95% confidence interval [CI]) was 41.0% (32.0, 49.8), and the median survival (95% CI) was 4.1 (3.4, 4.7) years. Independent prognostic factors for overall survival were the pathological T stage (pT4 vs. pT1- 3, adjusted hazard ratio [aHR]: 1.91, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.98, p = 0.005), time to metastases (synchronous vs. metachronous, aHR: 2.02, p = 0.02), and number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.13, p = 0.001). The 5-year recurrence-free survival rate (95% CI) was 21.1% (13.5, 29.7), with a median (95% CI) of 1.2 (0.9, 1.4) years. The primary tumor location (left- vs. right-sided colon, aHR: 4.77, p = 0.01; rectum vs. right-sided colon, aHR: 5.27, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.90, p = 0.03), number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.20, p = 0.001), and hospital volume (<10 vs. ≥10, aHR: 2.18, p = 0.02) were identified as independent prognostic factors for recurrence-free survival. Paraaortic lymph node recurrence was the most common at 33.3%. LIMITATIONS: Selection bias cannot be ruled out because of the retrospective nature of the study. CONCLUSIONS: Less than three paraaortic lymph node metastasis was a favorable prognostic factor for both overall survival and recurrence-free survival. However, paraaortic lymph node metastases were considered to be a systemic disease and the significance of resection was limited. See Video Abstract.

Clinical features associated with NeoRAS wild-type metastatic colorectal cancer A SCRUM-Japan GOZILA substudy.

"NeoRAS WT" refers to the loss of RAS mutations (MTs) following first-line treatment in metastatic colorectal cancer (mCRC). We evaluate the incidence and clinicopathological characteristics of NeoRAS WT mCRC using next-generation sequencing of plasma circulating tumor DNA. Patients with mCRC enrolled in the GOZILA study initially diagnosed with tissue RAS MT mCRC and received subsequent systemic therapy are eligible. NeoRAS WT is defined as the absence of detectable RAS MT in plasma and assessed in all eligible patients (Group A) and in a subgroup with at least one somatic alteration detected in plasma (Group B). Overall, 478 patients are included. NeoRAS WT prevalence is 19.0% (91/478) in Group A and 9.8% (42/429) in Group B. Absence of liver or lymph node metastasis and tissue RAS MTs other than KRAS exon 2 MTs are significantly associated with NeoRAS WT emergence. Overall, 1/6 and 2/6 patients with NeoRAS WT treated with anti-EGFR monoclonal antibodies (mAbs) show partial response and stable disease for ≥6 months, respectively. NeoRAS WT mCRC is observed at a meaningful prevalence, and anti-EGFR mAb-based therapy may be effective.

QUATTRO-II randomized trial: CAPOXIRI+bevacizumab vs. FOLFOXIRI+bevacizumab as first-line treatment in patients with mCRC.

BACKGROUND: The QUATTRO-II trial examined the efficacy and safety of capecitabine+oxaliplatin+irinotecan (CAPOXIRI)+bevacizumab (BEV) vs. 5-fluorouracil+folinic acid+oxaliplatin+irinotecan (FOLFOXIRI)+BEV in metastatic colorectal cancer (mCRC). METHODS: In this phase II study (ClinicalTrials.gov: NCT04097444; jRCTs041190072), patients were randomized (1:1) to FOLFOXIRI+BEV or CAPOXIRI+BEV. The induction treatment in the FOLFOXIRI+BEV/CAPOXIRI+BEV arms was continued for 8/6 cycles (maximum 12/8 cycles if feasible), and the maintenance treatment was 5-fluorouracil/leucovorin+BEV or capecitabine+BEV at the investigators' discretion. The primary endpoint was progression-free survival (PFS), with the two arms deemed equivalent if the hazard ratio (HR) of the point estimate was 0.80 < HR < 1.25. Secondary endpoints were overall response rate (ORR), overall survival (OS), incidence of adverse events (AEs), and patient-reported outcomes. FINDINGS: Overall, 51 and 52 patients were randomized to FOLFOXIRI+BEV and CAPOXIRI+BEV, respectively. The study met its primary endpoint; PFS at median follow-up of 23.7 months was 10.6 months (95% confidence interval [CI], 7.7-13.3) in the FOLFOXIRI+BEV arm vs. 10.9 months (95% CI, 9.3-14.3) in the CAPOXIRI+BEV arm (HR 1.114 [0.80 < HR < 1.25], p = 0.654). In the FOLFOXIRI+BEV vs. CAPOXIRI+BEV arms, the 2-year OS rate (95% CI) was 65.5% (49.5%-77.6%) vs. 74.3% (59.8%-84.2%), and the ORR (95% CI) was 76.5% (62.5%-87.2%) vs. 84.6% (71.9%-93.1%). Major (grade ≥3) AEs in the FOLFOXIRI+BEV vs. CAPOXIRI+BEV arms were neutropenia (68.6% vs. 40.4%), febrile neutropenia (9.8% vs. 11.5%), diarrhea (7.8% vs. 17.3%), and appetite loss (7.8% vs. 17.3%). CONCLUSION: CAPOXIRI+BEV was well tolerated with reduced hematological toxicity and efficacy comparable to those of FOLFOXIRI+BEV, providing a potentially convenient first-line treatment alternative to FOLFOXIRI+BEV in patients with mCRC. FUNDING: Chugai Pharmaceutical Co., Ltd.

Risk factors of bleeding during rectal cancer surgery in obese patients in Japan.

BACKGROUND: According to several clinical trials for patients with rectal cancer, laparoscopic surgery significantly reduces intraoperative complications and bleeding compared with laparotomy and demonstrated comparable long-term results. However, obesity is considered one of the risk factors for increased surgical difficulty, including complication rate, prolonged operation time, and bleeding. METHODS: Patients with clinical pathological stage II/III rectal cancer and a body mass index of ≥25 kg/m2 who underwent laparotomy or laparoscopic surgery between January 2009 and December 2013 at 51 institutions participating in the Japan Society of Laparoscopic Colorectal Surgery were included. These patients were divided into major bleeding (>500 mL) group and minor bleeding (≤500 mL) group. The risk factors of major bleeding were evaluated by univariate and multivariate analyses. RESULTS: This study included 517 patients, of which 74 (19.9%) experienced major bleeding. Patient characteristics did not significantly differ between the two groups. The major bleeding group had a longer operative time (p < 0.001) and a larger tumor size than the minor bleeding group (p = 0.011). In the univariate analysis, age >65 years, laparotomy, operative time >300 min, and multivisceral resection were significantly associated with intraoperative massive bleeding. In the multivariate analysis, age >65 years (odds ratio [OR], 2.29; 95% confidence interval [CI], 1.13-4.82), laparotomy (OR, 20.82; 95% CI, 11.56-39.75), operative time >300 min (OR, 5.39; 95% CI, 1.67-132), and multivisceral resection (OR, 10.72; 95% CI, 2.47-64.0) showed to be risk factors for massive bleeding. CONCLUSION: Age >65 years, laparotomy, operative time >300 min, and multivisceral resection were risk factors for massive bleeding during rectal cancer surgery in patients with obesity.

Monitoring ctDNA RAS Mutational Status in Metastatic Colorectal Cancer: A Trial Protocol of RAS-trace and RAS-trace-2 Studies.

Background: Spatial and temporal heterogeneities of RAS and other molecular genes should be considered in the treatment of metastatic colorectal cancer (mCRC) treated with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs); acquired RAS mutation is sometimes observed at disease progression of treatment with the anti-EGFR mAb. At the same time, discrepancy of RAS status from tissues and circulating tumor DNA (ctDNA) in the same patient is sometimes observed. Based on this, we commenced two observational studies to clarify these heterogeneities of RAS and BRAF in mCRC, using next generation sequencing from liquid biopsy. Methods/Design: RAS-trace study is an observational study to monitor ctDNA RAS/BRAF/PIK3CA status every 4-12 weeks using the Plasma-SeqSensei™ CRC RUO Kit (Sysmex Inostics GmbH) in mCRC with RAS/BRAF wild-type (wt) on tumor tissue. The primary endpoint was the time to the acquired RAS mutations. A total of 42 patients has been accrued. RAS-trace-2 study is also an observational study aimed at comparing the efficacy of the anti-EGFR mAb in ctDNA RAS/BRAF wt with ctDNA RAS or BRAF mutant mCRC patients, whose RAS/BRAF are wt in tumor tissue. The primary endpoint was progression-free survival in patients with ctDNA RAS/BRAF wt and RAS or BRAF mutant. A total of 240 patients will be accrued over 2 years. Discussion: These trials will help us understanding the clinical significance of spatial and temporal heterogeneities of RAS, BRAF and other genes, while optimizing the anti-EGFR mAb treatment strategies in mCRC.

Prospective observational study comparing the perioperative outcomes of laparoscopic colectomy with or without epidural anesthesia: the Kanagawa Yokohama Colorectal Cancer Study Group (KYCC) 1806.

PURPOSE: There have been no adequate comparisons of the efficacy, safety, and efficiency of analgesia after laparoscopic colorectal resection (LAC), with and without epidural anesthesia (EDA). METHODS: This was a multicenter prospective observational study of patients undergoing LAC. The primary end point was the mean visual analog scale (VAS) score on postoperative days (PODs) 1-7. The secondary end points were the highest VAS, complication rate, days to first ambulation and fatigue, length of hospital stay, and time to commencement of surgery. RESULTS: We compared an EDA group (Group E, n = 48) and a no-EDA group (Group O, n = 48) after matching. The mean VAS was not significantly different between the groups (28.7 vs. 30.1, p = 0.288). On assessing the secondary end points, the highest VAS was not significantly different between the groups. In fact, the VAS was lower in Group E only on POD 2. There was no difference in the incidence of complications, the time to first postoperative evacuation was shorter in Group E, and postoperative hospitalization was similar. The time to surgery was shorter in Group O. CONCLUSION: These results suggest that LAC without EDA is a feasible option, but with the early and regular use of adjunctive measures to provide more stable analgesia.

Primary omental smooth muscle tumor in an adult male: a diagnostic dilemma for leiomyoma: a case report.

BACKGROUND: The greater omentum comprises peritoneal, adipose, vascular, and lymphoid tissues. Most omental malignancies are metastatic tumors, and the incidence of primary tumors is rare. We report on a prior omental smooth muscle tumor case in an adult male patient. CASE PRESENTATION: A 54-year-old Japanese male patient with no relevant medical history was diagnosed with an abdominal mass during a routine medical checkup. Subsequent contrast-enhanced computed tomography revealed a mass of approximately 3 cm in size in the greater omentum, and a laparotomy was performed. A 27 × 25 × 20 mm raised lesion was found in the omentum. Microscopically, spindle cells were observed and arranged in whorls and fascicles. Individual tumor cells had short spindle-shaped nuclei with slightly increased chromatin and were characterized by a slightly eosinophilic, spindle-shaped cytoplasm. The mitotic count was less than 1 per 50 high-power fields. The tumor cells showed positive immunoreactivity for α smooth muscle actin, HHF35, and desmin on immunohistochemical examination. The Ki-67 labeling index using the average method was 1.76% (261/14806). No immunoreactivity was observed for any of the other tested markers. We considered leiomyoma owing to a lack of malignant findings. However, primary omental leiomyoma has rarely been reported, and it can be difficult to completely rule out the malignant potential of smooth muscle tumors in soft tissues. Our patient was decisively diagnosed with a primary omental smooth muscle tumor considering leiomyoma. Consequently, the patient did not undergo additional adjuvant therapy and was followed up. The patient was satisfied with treatment and showed neither recurrence nor metastasis at the 13-month postoperative follow-up. DISCUSSION AND CONCLUSION: We encountered a primary smooth muscle tumor of the greater omentum with no histological findings suggestive of malignancy in an adult male patient. However, omental smooth muscle tumors are extremely difficult to define as benign, requiring careful diagnosis. Further case reports with long-term follow-up and case series are required to determine whether a true omental benign smooth muscle tumor (leiomyoma) exists. In addition, proper interpretation of the Ki-67 labeling index should be established. This case study is a foundation for future research.

Lymphatic spread patterns in young versus elderly patients with stage III colon cancer.

BACKGROUND: The anatomical pattern of lymph nodes spread differs between young (aged 45 years or younger) and elderly (aged 80 years or older) patients with stage III colon cancer and is poorly investigated. METHODS: Two groups of patients (young and elderly) with stage III colon cancer who underwent upfront extensive (D3) lymphadenectomy at eight Japanese centres between 1998 and 2018 were retrospectively analysed. The primary endpoint was the proportion of positive central lymph nodes. The lymph nodes spreading pattern and its prognostic impact on recurrence-free survival and overall survival in the two groups were also compared. RESULTS: Two hundred and ten young patients and 348 elderly patients were identified and compared. The total number of lymph nodes harvested and the total number of invaded lymph nodes were significantly higher in younger patients compared with elderly patients (median of 31.5 (3-151) versus 21 (3-116), P < 0.001 and median of 3 (1-21) versus 2 (1-25), P < 0.001 respectively). The proportion of positive central lymph nodes were higher in younger patients than in elderly patients (9.52% (95% c.i. 6.24 to 14.2%) versus 4.59% (95% c.i. 2.84 to 7.31%), P = 0.012). In multivariate models for recurrence-free survival, central lymph nodes invasion were identified as a poor prognostic factor in younger patients (HR 5.21 (95% c.i. 1.76 to 15.39)) but not in elderly patients (HR 1.73 (95% c.i. 0.80 to 3.76)). CONCLUSION: Young patients with stage III colon cancer have a higher risk of central lymph nodes invasion, suggesting a more aggressive disease biology. The presence of central lymph nodes invasion are associated with a worse outcome in young patients.

Temporal dynamics of RAS mutations in circulating tumor DNA in metastatic colorectal cancer: clinical significance of mutation loss during treatment.

PURPOSE: In metastatic colorectal cancer (mCRC), RAS mutation loss may occur during the standard-of-care regimen. In this study, we aimed to investigate the temporal dynamics of the RAS gene and its clinical significance. METHODS: This was a retrospective, single-center study that included 82 patients with tissue RAS-mutant (RAS-MT) mCRC who underwent circulating tumor DNA (ctDNA) RAS monitoring between January, 2013-April, 2023. Patients were analyzed for the rate of change over time to acquired RAS mutation loss (aRAS-ML) and clinicopathological factors. The prognostic relevance of mutation loss was assessed. RESULTS: aRAS-ML was detected in 33 (40.2%) patients, 32 of whom had a mutation loss in the first ctDNA RAS assay. Patients with a RAS mutation detected in the first assay had a median time of 8 months until the second ctDNA RAS assay, with 4.5% cases newly converted to aRAS-ML; no new conversions were detected at the third assay. The aRAS-ML group exhibited more single-organ metastases in the target organ during ctDNA measurement (aRAS-ML: 84.8% vs. RAS-MT: 59.2%, p = 0.02). Of the 33 patients with aRAS-ML, seven (21.2%) received anti-epidermal growth factor receptor (EGFR) therapy, with a median progression-free survival of 8 months. Multivariate analysis revealed that persistent ctDNA RAS mutation was an independent prognostic factor for overall survival (hazard ratio: 2.7, 95% confidence interval: 1.1-6.3, p = 0.02). CONCLUSION: The rate of ctDNA mutation loss in patients with RAS-MT mCRC decreases over time. Therefore, using a ctDNA RAS assay early in treatment will assist in challenging the use of EGFR regimens.

Dimension reduction of microbiome data linked Bifidobacterium and Prevotella to allergic rhinitis.

Dimension reduction has been used to visualise the distribution of multidimensional microbiome data, but the composite variables calculated by the dimension reduction methods have not been widely used to investigate the relationship of the human gut microbiome with lifestyle and disease. In the present study, we applied several dimension reduction methods, including principal component analysis, principal coordinate analysis (PCoA), non-metric multidimensional scaling (NMDS), and non-negative matrix factorization, to a microbiome dataset from 186 subjects with symptoms of  allergic rhinitis (AR) and 106 controls. All the dimension reduction methods supported that the distribution of microbial data points appeared to be continuous rather than discrete. Comparison of the composite variables calculated from the different dimension reduction methods showed that the characteristics of the composite variables differed depending on the distance matrices and the dimension reduction methods. The first composite variables calculated from PCoA and NMDS with the UniFrac distance were strongly associated with AR (FDR adjusted P = 2.4 × 10-4 for PCoA and P = 2.8 × 10-4 for NMDS), and also with the relative abundance of Bifidobacterium and Prevotella. The abundance of Bifidobacterium was also linked to intake of several nutrients, including carbohydrate, saturated fat, and alcohol via composite variables. Notably, the association between the composite variables and AR was much stronger than the association between the relative abundance of individual genera and AR. Our results highlight the usefulness of the dimension reduction methods for investigating the association of microbial composition with lifestyle and disease in clinical research.

True significance of the number of retrieved lymph nodes in stage II colon cancer resected by minimally invasive surgery: Influence of tumor sidedness.

BACKGROUND: In patients with stage II colon cancer (CC) undergoing minimally invasive surgery, the association between the clinical significance of lymph node yield and tumor localization remains unknown. We aimed to determine the optimal number of lymph nodes to be retrieved based on tumor localization in patients with stage II CC undergoing minimally invasive surgery. METHODS: This was a multicenter retrospective study. Overall, 263 patients with stage II CC who underwent laparoscopic surgery between January 1, 2008 and December 31 were enrolled. The primary outcome was the optimal number of lymph nodes retrieved based on tumor localization. RESULTS: The median number of retrieved lymph nodes was 30 and 26 in the right-(n = 125) and left-sided (n = 138) CC groups, respectively (p = .0007). Inadequate dissection (<12 nodes) occurred in 4.2% of patients: 1.6% in the right-sided CC group and 6.5% in the left-sided CC group. Multivariate Cox regression analysis showed a decreasing trend in adjusted hazard ratios with increasing nodes, with an optimal cutoff of 15 lymph nodes in the left-sided CC group (adjusted hazard ratio, 5.868; 95% confidence interval, 1.247-27.62; p = .02). Lymph node yield was not independently associated with survival in the right-sided CC group. CONCLUSIONS: For patients with left-sided stage II CC undergoing laparoscopic surgery, aiming for at least 15 retrieved lymph nodes may be optimal for accurate staging and prognostic assessment. The optimal lymph node yield likely varies based on tumor location, requiring further investigation in right-sided CC.

Safety and Efficacy of Encorafenib, Binimetinib, and Cetuximab for BRAFV600E-Mutant Metastatic Colorectal Cancer: Results of the Japanese Expanded Access Program.

BACKGROUND: The phase 3 BEACON CRC study demonstrated the survival benefits of encorafenib and cetuximab, with or without binimetinib (the BEACON triplet or doublet regimen), for BRAFV600E-mutant metastatic colorectal cancer (mCRC). This expanded access program (EAP) and subsequent follow-up study assessed the efficacy and safety of the BEACON triplet regimen in Japanese patients with BRAFV600E-mutant mCRC. MATERIALS AND METHODS: The EAP was an open-label, single-arm study including Japanese patients with BRAFV600E-mutant mCRC whose disease progressed after 1 to 2 prior regimens. The patients received the BEACON triplet regimen with 28-day cycles. The subsequent follow-up study assessed the survival outcomes following EAP completion. Safety was assessed only during the EAP. RESULTS: Among the 86 enrolled patients, 81 received the BEACON triplet regimen. The objective response rate and median progression-free survival were 27.6% (95% confidence interval [CI], 18.0%-39.1%) and 5.26 (95% CI, 4.14-5.52) months, respectively. Grade 3 to 4 adverse events and treatment-related adverse events occurred in 43.2% and 28.4% of patients, respectively. No new safety signals were observed during the EAP. Among 58 patients with confirmed survival at EAP completion, 57 were included in the follow-up study. With a median observation period of 9.17 months through the EAP and follow-up study, the median overall survival was 10.38 (95% CI, 9.00-16.16) months. CONCLUSION: The efficacy and safety of the BEACON triplet regimen in Japanese patients with BRAFV600E-mutant mCRC were consistent with those reported in the BEACON CRC trial, supporting its use as a standard treatment for pretreated patients with BRAFV600E-mutant mCRC.

Plasma Angiogenic Factors as Predictors of the Efficacy of Second-line Chemotherapy Combined with Angiogenesis Inhibitors in Metastatic Colorectal Cancer: Results From the GI-SCREEN CRC-Ukit Study.

BACKGROUND: The significance of angiogenic factors as predictors of second-line (2L) chemotherapy efficacy when combined with angiogenesis inhibitors for metastatic colorectal cancer (mCRC) remains unestablished. PATIENTS AND METHODS: In this multicenter prospective observational study, 17 angiogenic factors were analyzed in plasma samples collected at pretreatment and progression stages using a Luminex multiplex assay. Patients who received chemotherapy plus bevacizumab (BEV group), FOLFIRI plus ramucirumab (RAM group), or FOLFIRI plus aflibercept (AFL group) as the 2L treatment were included. Interactions between pretreatment and treatment groups for progression-free survival (PFS), overall survival (OS), and response rate (RR) were assessed using the propensity-score weighted Cox proportional hazards model. RESULTS: From February 2018 to September 2020, 283 patients were analyzed in the 2L cohort. A strong interaction was observed for PFS between BEV and RAM with HGF, sNeuropilin-1, sVEGFR-1, and sVEGFR-3. Interactions for RR between the BEV and RAM groups were observed for sNeuropilin-1 and sVEGFR-1. Contrarily, OS, PlGF, sVEGFR-1, and sVEGFR-3 differentiated the treatment effect between BEV and AFL. Plasma samples were evaluable for dynamic analysis in 203 patients. At progression, VEGF-A levels significantly decreased in the BEV group and increased in the RAM and AFL groups. CONCLUSION: The pretreatment plasma sVEGFR-1 and sVEGFR-3 levels could be predictive biomarkers for distinguishing BEV and RAM when combined with chemotherapy in 2L mCRC treatment. Based on the VEGF-A dynamics at progression, selecting RAM or AFL for patients with significantly elevated VEGF-A levels may be a 2L treatment strategy, with BEV considered for the third-line treatment. CLINICAL TRIAL NUMBER: UMIN000028616.

Baseline ctDNA gene alterations as a biomarker of survival after panitumumab and chemotherapy in metastatic colorectal cancer.

Certain genetic alterations and right-sided primary tumor location are associated with resistance to anti-epidermal growth factor (EGFR) treatment in metastatic colorectal cancer (mCRC). The phase 3 PARADIGM trial (n = 802) demonstrated longer overall survival with first-line anti-EGFR (panitumumab) versus antivascular endothelial growth factor (bevacizumab) plus modified FOLFOX6 in patients with RAS wild-type mCRC with left-sided primary tumors. This prespecified exploratory biomarker analysis of PARADIGM (n = 733) evaluated the association between circulating tumor DNA (ctDNA) gene alterations and efficacy outcomes, focusing on a broad panel of gene alterations associated with resistance to EGFR inhibition, including KRAS, NRAS, PTEN and extracellular domain EGFR mutations, HER2 and MET amplifications, and ALK, RET and NTRK1 fusions. Overall survival was prolonged with panitumumab plus modified FOLFOX6 versus bevacizumab plus modified FOLFOX6 in patients with ctDNA that lacked gene alterations in the panel (that is, negative hyperselected; median in the overall population: 40.7 versus 34.4 months; hazard ratio, 0.76; 95% confidence interval, 0.62-0.92) but was similar or inferior with panitumumab in patients with ctDNA that contained any gene alteration in the panel (19.2 versus 22.2 months; hazard ratio, 1.13; 95% confidence interval, 0.83-1.53), regardless of tumor sidedness. Negative hyperselection using ctDNA may guide optimal treatment selection in patients with mCRC. ClinicalTrials.gov registrations: NCT02394834 and NCT02394795 .

Clinical significance of the post/preoperative anti-p53 antibody ratio in predicting the prognosis of patients with colorectal cancer after curative surgery and its usefulness in combination with carcinoembryonic antigen.

[Introduction] Anti-p53 antibody (p53Ab) is useful for monitoring colorectal cancer (CRC) recurrence. We retrospectively analyzed the clinical impact of p53Ab ratio (p53R) before and after surgery to predict recurrence in patients with CRC. [Methods] In total, 1,223 patients with stage I-III CRC who underwent curative surgery between January 2005 and December 2019 were enrolled in this retrospective study. In patients with elevated p53Ab levels, p53R was calculated by measuring p53Ab levels within one month preoperatively and three months postoperatively. The optimal p53R level was determined, and its relationship with clinicopathological factors and prognosis was examined. We also evaluated the efficacy of the combination of p53R and preoperative carcinoembryonic antigen (CEA) values. [Results] Overall, 341 patients (27.9%) showed elevated p53Ab levels. Preoperative p53Ab levels were significantly associated with tumor location, lymphatic invasion, and venous invasion. The p53R level was significantly higher in patients with recurrent disease. Patients with high p53R levels had significantly shorter relapse-free survival (RFS) than those with low p53R levels (p < 0.001). When p53R was combined with preoperative CEA values, specificity improved to 0.97, with an accuracy of 0.88. [Conclusion] In patients with CRC and elevated preoperative p53Ab levels, p53R expression may be prognostically useful after radical resection. Furthermore, the combination of p53R and preoperative CEA levels may be useful for postoperative follow-ups.

Prognostic Relevance of Primary Tumor Sidedness in Early-stage Colorectal Cancer: An Integrated Analysis of 4 Randomized Controlled Trials (JCOG2003A).

OBJECTIVE: The aim of this study was to determine the genuine prognostic relevance of primary tumor sidedness (PTS) in patients with early-stage colorectal cancer (CRC). BACKGROUND: The prognostic relevance of PTS in early-stage CRC remains a topic of debate. Several large epidemiological studies investigated survival only and did not consider the risk of recurrence so far. METHODS: Patients with stage II/III adenocarcinoma of the colon and upper rectum from 4 randomized controlled trials were analyzed. Survival outcomes were compared according to the tumor location: right-sided (cecum to transverse colon) or left-sided (descending colon to upper rectum). RESULTS: A total of 4113 patients were divided into a right-sided group (N=1349) and a left-sided group (N=2764). Relapse-free survival after primary surgery was not associated with PTS in all patients and each stage [hazard ratio (HR) adjusted =1.024 (95% CI: 0.886-1.183) in all patients; 1.327 (0.852-2.067) in stage II; and 0.990 (0.850-1.154) in stage III]. Also, overall survival after primary surgery was not associated with PTS in all patients and each stage [HR adjusted =0.879 (95% CI: 0.726-1.064) in all patients; 1.517 (0.738-3.115) in stage II; and 0.840 (0.689-1.024) in stage III]. In total, 795 patients (right-sided, N=257; left-sided, N=538) developed recurrence after primary surgery. PTS was significantly associated with overall survival after recurrence (HR adjusted =0.773, 95% CI: 0.627-0.954). CONCLUSIONS: PTS had no impact on the risk of recurrence for stage II/III CRC. Treatment stratification based on PTS is unnecessary for early-stage CRC.

A multicenter prospective observational study of lymph node metastasis patterns and short-term outcomes of extended lymphadenectomy in right-sided colon cancer.

Background: The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer. Methods: This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery. Results: Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%). Conclusion: Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

Sidedness-Dependent Prognostic Impact of Gene Alterations in Metastatic Colorectal Cancer in the Nationwide Cancer Genome Screening Project in Japan (SCRUM-Japan GI-SCREEN).

The treatment strategies and prognoses of patients with metastatic colorectal cancer (CRC) differ according to the sidedness of the primary tumor. TP53 gain-of-function (GOF) and non-GOF variants have been reported to be differentially associated with prognosis by sidedness. We aimed to evaluate the sidedness-dependent prognostic impact of gene alterations in metastatic CRC. Patients enrolled between April 2017 and March 2019 were included in this study. Those excluded were individuals whose tumor tissues were obtained after chemotherapy and those who were enrolled in the study more than six months after starting first-line chemotherapy. Finally, we assessed 531 patients who underwent complete gene sequencing. The study revealed a significant difference in overall survival between individuals with left-sided CRC (n = 355) and right-sided colon cancer (CC) (n = 176) when considering the TP53 non-GOF variant, KRAS wild-type, NOTCH1 wild-type, NOTCH1 covariant, NOTCH3 sole variant, and MYC amplification. Multivariate analysis on each side revealed that the TP53 GOF and KRAS variants were independent poor prognostic factors for left-sided CRC (p = 0.03 and p < 0.01, respectively), and the TP53 non-GOF variant, BRAF V600E, and MYC amplification for right-sided CC (p < 0.05, p < 0.01, and p = 0.02, respectively). The NOTCH3 sole variant was an independent and favorable prognostic factor for left-sided CRC (p < 0.01). The prognostic significance of gene alterations differed between left-sided CRC and right-sided CC.