Utilization of tissue-free minimal residual disease testing in colorectal cancer patients from Asia and Middle East.

Introduction: The presence of minimal residual disease (MRD) after curative-intent surgery for early-stage cancers is associated with disease recurrence. Circulating tumour deoxyribonucleic acid (ctDNA) has emerged as a promising biomarker for MRD assessment in patients with colorectal cancer (CRC) who have undergone surgery or completed adjuvant therapy. MRD tests are already available for use in clinics; however, treatment decisions following MRD results obtained in routine practice are infrequently described. Methods: In this observational study, we report on the real-world clinical use of Guardant Reveal, a validated tissue-free MRD assay, in the first 215 consecutive patients (279 samples) with CRC tested in Asia and the Middle East. Results: Overall, 22% of patients had ctDNA detected in their first MRD test, and the frequency of ctDNA positivity increased with increasing tumour stage. 132 samples were tested with an earlier version of Guardant Reveal, one that assessed both genomic and epigenomic features. An updated version of the assay assesses only ctDNA methylation data and was used for the remaining 147 samples. In patients with stage II CRC, 71% of tests were ordered within 12 weeks after tumour resection, while for patients with stage III disease, 69% of tests were ordered after completion of all curative-intent treatment. Discussion: Clinical cases utilizing tissue-free MRD assessment are described.

Tumor Differentiation as a Prognostic Marker in Clinically Staged T1bN0 Esophageal Adenocarcinoma.

Current guidelines recommend that clinically staged T1N0 esophageal cancers are to be referred to surgery or endoscopic resection. Using the National Cancer Database, we identified 733 individuals with clinically staged T1N0 esophageal carcinoma, who underwent upfront surgery and did not receive any prior treatment. We assessed upstaging, which was defined as ≥ T2 disease or positive lymph nodes. Poorly differentiated adenocarcinomas were associated with upstaging, whereas squamous cell carcinomas were not. Specifically, the percentage of upstaging among individuals with clinically staged T1b and poorly differentiated tumor was 33.8%. Therefore, clinically staged T1bN0 poorly differentiated esophageal adenocarcinomas are at high risk for upstaging following surgery.

Benefit for single-agent adjuvant chemotherapy in elderly patients with locally advanced gastric adenocarcinoma.

BACKGROUND: Current NCCN guidelines exclude the possibility of using single-agent adjuvant chemotherapy in locally advanced gastric adenocarcinoma, while allowing doublet chemotherapy. However, single-agent adjuvant chemotherapy is a valid treatment option in other gastrointestinal malignancies, preferred for elderly and/or frail patients. The current study used a nationwide oncology database to assess the benefit of single-agent adjuvant chemotherapy, specifically in the elderly population. METHODS: Using the National Cancer Database (2004-2016) we identified 1953 individuals with non-metastatic gastric adenocarcinoma who underwent upfront D2 gastrectomy with pathologic stage ≥ T3 or Npos and free surgical margins, and had not received either preoperative chemotherapy or pre-/postoperative radiotherapy. We used IPTW analysis to compare overall survival between individuals receiving either single- or multi-agent adjuvant chemotherapy, or referred to observation alone. RESULTS: Individuals receiving single-agent chemotherapy had an overall survival benefit compared with observation alone, with an HR of 0.70 (95% CI 0.55-0.88, p < 0.001). Individuals over the age of 65 had an OS benefit with an HR of 0.61 (95% CI 0.46-0.82, p < 0.001). Comparing individuals over the age of 65 receiving single- vs. multi-agent chemotherapy, there was no overall survival difference with an HR of 0.87 (95% CI 0.64-1.18, p = 0.38). CONCLUSIONS: Single-agent adjuvant chemotherapy with a fluoropyrimidine in locally advanced gastric adenocarcinoma following D2 gastrectomy can improve overall survival in elderly patients. Clinicians may consider using either capecitabine or 5-FU as a treatment option in the adjuvant setting for this age group.

Targeting autocrine amphiregulin robustly and reproducibly inhibits ovarian cancer in a syngeneic model: roles for wildtype p53.

Ovarian cancer (OvCA) remains one of the most devastating malignancies, but treatment options are still limited. We report that amphiregulin (AREG) can serve as an effective and safe pharmacological target in a syngeneic murine model. AREG is highly abundant in abdominal fluids of patients with advanced OvCa. In immunocompetent animals, depletion or overexpression of AREG respectively prolonged or shortened animal survival. A new antibody we generated in AREG-knockout mice recognized murine AREG and reproducibly prolonged animal survival in the syngeneic model. The underlying mechanism likely involves binding of wildtype p53 to AREG's promoter and autocrine activation of the epidermal growth factor receptor (EGFR), a step blocked by the antibody. Accordingly, depletion of p53 downregulated AREG secretion and conferred tolerance, whereas blocking an adaptive process involving CXCL1, which transactivates EGFR, might increase therapeutic efficacy. Consistent with these observations, analysis of OvCa patients revealed that high AREG correlates with poor prognosis of patients expressing wildtype TP53. In conclusion, clinical tests of the novel antibody are warranted; high AREG, normal TP53, and reduced CXCL1 activity might identify patients with OvCa who may derive therapeutic benefit.

Repeat Cytoreductive Surgery and Intraperitoneal Chemotherapy for Colorectal Cancer Peritoneal Recurrences is Safe and Efficacious.

BACKGROUND: Cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC) for colorectal cancer peritoneal metastases (CRPM) is associated with improved survival in patients with historically dismal prognosis. Nonetheless, peritoneal recurrences remain common and represent a difficult challenge in these patients' management. Repeat CRS/HIPEC is associated with even greater morbidity and its survival benefit has not yet been clearly demonstrated. METHODS: We retrospectively reviewed our prospectively maintained database and aimed to assess the safety and oncological efficacy of repeat CRS/HIPEC. RESULTS: Two hundred thirty-two patients underwent an initial CRS/HIPEC, whereas 30 subsequently had repeat CRS/HIPEC for CRPM. Groups were similar in demographics, comorbidities, and peritoneal cancer index (PCI). No significant difference in morbidity, hospital stay, or reoperation rate was noted between initial and repeat procedures. Patients who underwent repeat CRS/HIPEC had a median overall survival of 68 months versus 51 months in patients who did not undergo repeat procedure for their peritoneal recurrence (p = 0.03). Disease-free survival (DFS) in patients after repeat and after initial procedure were similar with median of 9.6 versus 12 months, respectively (p = 0.083). Univariate analysis demonstrated that PCI, DFS, and repeat procedure displayed significant factors on outcomes in patients with peritoneal recurrences, whereas PCI > 16 and DFS remained independent predictors on multivariable analysis. CONCLUSIONS: Our analysis, which represents the largest series to date of repeat CRS/HIPEC for CRPM, indicates that this approach as a part of multimodal therapy is both safe and efficacious in appropriately selected patients.

Perioperative and Oncological Outcomes of Combined Hepatectomy with Complete Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Metastatic Colorectal Cancer.

BACKGROUND: Synchronous peritoneal and liver metastasis in colorectal cancer is a relative contraindication for curative surgery. We aimed to evaluate the safety and oncological outcomes of combined treatment of peritoneal and liver metastasis. METHODS: We conducted a retrospective analysis of metastatic colorectal cancer patients from two prospective databases: peritoneal surface malignancy (n = 536) and hepatobiliary (n = 286). We compared 60 patients treated with cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) and hepatectomy; 80 patients treated with cytoreduction and HIPEC only; and 63 patients treated with hepatectomy alone. RESULTS: No differences in demographics were observed between the groups. Median hospital and intensive care unit (ICU) stay was shorter in group C (7 and 1 days, respectively) versus groups A and B (13 and 1 days, and 12 and 1 days, respectively; p < 0.001). Postoperative complications were not significantly different. Median follow-up was 18.6, 23.1, and 30.6 months for groups A, B, and C, respectively. Estimated 5-year overall survival (OS) was 48.8% (group A), 55.4% (group B), and 60.2% (group C) [p = 0.043 for group A vs. group C], and estimated 5-year disease-free survival (DFS) was 14.2% (group A), 23.0% (group B), and 18.6% (group C). Five-year OS was superior in group C compared with group A (p = 0.043), and DFS was superior in group C compared with groups A and B (p = 0.043 and 0.03, respectively). The peritoneum was the site of first recurrence in groups A and B (23.3% and 32.5%, respectively), and the liver was the site of first recurrence in group C (44.4%). CONCLUSIONS: We report favorable perioperative and oncological outcomes in combined cytoreduction/HIPEC and hepatectomy for patients with peritoneal and liver metastasis. Surgical intervention after multidisciplinary discussion should be considered in patients with both peritoneal and hepatic lesions when complete cytoreduction is feasible.

Prognostic Implications of Tumor Differentiation in Clinical T1N0 Gastric Adenocarcinoma.

BACKGROUND: Current guidelines recommend neoadjuvant chemotherapy in patients with locoregional gastric adenocarcinoma. Patients diagnosed with early stage gastric adenocarcinoma are usually managed with upfront surgical intervention. However, pathologic staging in a subset of these clinically staged patients identifies more advanced locoregional disease requiring adjuvant treatment. Therefore, identifying these patients prior to surgical intervention is critical to ensure employment of the appropriate treatment paradigm. The aim of the current study was to define patient characteristics associated with clinical understaging in early gastric cancer. METHODS: Using the National Cancer Database (2004-2014) we identified 3,892 individuals with clinical T1N0 gastric adenocarcinoma who underwent upfront definitive surgery, had negative surgical margins, and did not receive preoperative chemotherapy or radiotherapy. Patient characteristics were compared between those with pathologic stage T1N0 disease and those who were upstaged upon surgery. RESULTS: Twenty-seven percent of clinical T1N0 gastric adenocarcinomas had a change in stage because of pathologically defined ≥T2 disease or positive lymph nodes. Individuals who were upstaged had a higher tumor grade compared with those with pathologic stage T1N0 disease. Specifically, 41.9% (530/1,264) of individuals with a poorly differentiated tumor were upstaged, compared with only 10.7% (70/656) with a well-differentiated tumor. Approximately 75% of cases involved upstaging because of T misclassification. The highest percentage of upstaging was shown for tumors located at the fundus and body of the stomach. CONCLUSION: Upstaging of clinical T1N0 gastric adenocarcinoma is characterized by higher tumor grade and is mostly a result of a change in T stage. These findings mandate thorough workup in order to identify patients with clinically staged T1N0 disease requiring preoperative chemotherapy. IMPLICATIONS FOR PRACTICE: Upstaging of clinical T1N0 gastric adenocarcinoma is characterized by higher tumor grade and is mostly a result of a change in T stage. These findings mandate thorough workup in order to identify patients with clinically staged T1N0 disease requiring preoperative chemotherapy.

Clinical Characteristics and Prognosis of Gastric Cancer Patients with BRCA 1/2 Germline Mutations: Report of Ten Cases and a Literature Review.

BACKGROUND: The prognosis of gastric cancer (GC) is poor with a median overall survival (OS) of less than 12 months in advanced-stage disease. The search for distinct genetic subgroups of GC patients and predictive biomarkers is ongoing. While BRCA1 or BRCA2 germline mutations (gBRCAm) have potential therapeutic implications in ovarian, breast and pancreatic cancers, their significance in GC patients has not been established. PATIENTS AND METHODS: A retrospective multi-center data analysis of GC patients with gBRCAm was conducted, detailing the clinical characteristics and disease course in this unique subset of patients. RESULTS: Ten GC patients with gBRCAm were identified, six of them with metastatic disease. The median OS of all ten GC patients was 47.5 (13-192) months. Median OS for patients diagnosed with operable disease was 55.5 (13-192) months and of the patients with metastatic disease (calculated from metastatic disease diagnosis) 32 (15-52) months with an exceptional 1-, 2- and 3-year survival rate of 100%, 83.3% and 50%, respectively. CONCLUSION: These preliminary data suggest that gBRCAm in GC patients are associated with a favorable prognosis. Furthermore, gBRCAm might be a predictive biomarker to DNA-damaging agents response in GC patients, similarly to its established role in other malignancies. Further research is needed to confirm our findings.

Assessing the effects of beta-blockers on pancreatic cancer risk: A nested case-control study.

PURPOSE: Both ß1- and ß2-adrenoceptor proteins were detected on the cell surface of pancreatic ductal adenocarcinoma. The current study evaluated the association between beta-blocker use and pancreatic cancer risk. METHODS: We conducted a nested case-control study in a large population representative database. Each pancreatic cancer case was matched with four controls based on age, sex, practice site, and duration of follow-up using incidence density sampling. Beta-blocker use was defined as any prescription prior to index date and was stratified into non-selective and selective ß1 -blockers. The odds ratios (ORs) and 95% confidence intervals (95% CIs) for pancreatic cancer risk associated with beta-blocker use was estimated using conditional logistic regression. RESULTS: The study included 4113 patients with pancreatic cancer and 16 072 matched controls. When compared to never users, there was no association between any beta-blocker use and pancreatic cancer risk (adjusted OR 1.06, 95% CI 0.97-1.16, P = .16). Analysis by receptor selectivity showed use of non-selective beta-blockers for more than 2 years was associated with a reduced pancreatic cancer risk (OR 0.75, 95% CI 0.57-1.00, P = .05). When compared to former users both users of selective ß1-blockers and non-selective beta-blockers had a reduced pancreatic cancer risk (OR 0.78, 95% CI 0.67-0.90, P = .001) and (OR 0.67, 95% CI 0.49-0.92, P = .01), respectively. CONCLUSION: Beta-blocker use was not associated with increased pancreatic cancer risk. However, long-term use of beta-blockers may be associated with decreased pancreatic cancer risk.

Distinguishing Features of Cetuximab and Panitumumab in Colorectal Cancer and Other Solid Tumors.

Cetuximab and panitumumab are two distinct monoclonal antibodies (mAbs) targeting the epidermal growth factor receptor (EGFR), and both are widely used in combination with chemotherapy or as monotherapy to treat patients with RAS wild-type metastatic colorectal cancer. Although often considered interchangeable, the two antibodies have different molecular structures and can behave differently in clinically relevant ways. More specifically, as an immunoglobulin (Ig) G1 isotype mAb, cetuximab can elicit immune functions such as antibody-dependent cell-mediated cytotoxicity involving natural killer cells, T-cell recruitment to the tumor, and T-cell priming via dendritic cell maturation. Panitumumab, an IgG2 isotype mAb, does not possess these immune functions. Furthermore, the two antibodies have different binding sites on the EGFR, as evidenced by mutations on the extracellular domain that can confer resistance to one of the two therapeutics or to both. We consider a comparison of the properties of these two antibodies to represent a gap in the literature. We therefore compiled a detailed, evidence-based educational review of the known molecular, clinical, and functional differences between the two antibodies and concluded that they are distinct therapeutic agents that should be considered individually during treatment planning. Available data for one agent can only partly be extrapolated to the other. Looking to the future, the known immune activity of cetuximab may provide a rationale for this antibody as a combination partner with investigational chemotherapy plus immunotherapy regimens for colorectal cancer.

Lung Metastasis Predicts Better Prognosis in Metastatic Colorectal Cancer With Mutated KRAS.

BACKGROUND: Previous studies have shown that prognosis in metastatic colorectal cancer (mCRC) might vary according to sites of metastasis. We evaluated prognosis in individuals with mCRC and single-site metastasis, according to several clinical and genetic variables. PATIENTS AND METHODS: Using the National Cancer Database we identified 58,044 mCRC patients with a synchronous single site of metastasis. We first examined the effect of metastasis site on prognosis. In a secondary analysis, among individuals who had not undergone surgery or received radiotherapy, we examined the prognostic value of chemotherapy intensity, Kirsten ras (KRAS) status, primary tumor location and carcinoembryonic antigen (CEA) levels. RESULTS: Individuals with lung metastasis had the best prognosis (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.77-0.83), followed by those with liver metastasis (HR, 1.11; 95% CI, 1.07-1.15), whereas those with bone or brain metastasis had the worse prognosis. In a subgroup analysis, we assessed prognosis among individuals who received multiagent chemotherapy and had not undergone surgery or received radiotherapy. Individuals with lung metastasis and mutant KRAS had better prognosis compared with those with liver metastasis (HR, 0.69; 95% CI, 0.54-0.88), regardless of primary tumor location or CEA levels. CONCLUSION: Single-site metastasis to the lungs is associated with better prognosis in mCRC, specifically among patients with KRAS mutant tumors.

Postoperative Radiation for Pathologic Stage T4 Colon Cancers Receiving Adjuvant Chemotherapy.

BACKGROUND: Previous small retrospective studies have suggested a benefit, mainly in preventing local recurrence, for postoperative radiation in nonmetastatic pathologic stage T4 colon cancers in patients who did not receive adjuvant chemotherapy. Current guidelines recommend postoperative radiation in nonmetastatic T4 colon cancers with penetration to a fixed structure, as well as for all patients with positive surgical margins. We aimed to assess the survival benefit of postoperative radiation in individuals with T4 colon cancers who received adjuvant chemotherapy. METHODS: Using the National Cancer Data Base (2004-2014), we identified 20,967 and 5882 individuals with nonmetastatic pathologic stage T4 colon cancer treated with adjuvant chemotherapy who had negative or positive surgical margins, respectively. We used multivariate Cox regression to evaluate the effect of postoperative radiation on overall survival. In a secondary analysis, we stratified individuals according to chemotherapy intensity, pathologic N stage, and primary tumor location. RESULTS: Postoperative radiation did not improve overall survival in individuals with positive surgical margins (hazard ratio = 1.05 [95% CI, 0.96-1.16]). This lack of survival benefit was noted regardless of chemotherapy regimen used, with adjusted hazard ratios of 1.11 (95% CI, 0.94-1.31) and 0.96 (0.85-1.09) for single-agent and doublet chemotherapy, respectively. Similarly, pathologic N stage and primary tumor location did not affect survival. In individuals with negative surgical margins, there was a detrimental effect for postoperative radiation, with an adjusted hazard ratio of 1.19 (95% CI, 1.10-1.29). CONCLUSION: Postoperative radiation did not improve overall survival in individuals with pathologic stage T4 colon cancer who had either negative or positive surgical margins and who received adjuvant chemotherapy.

Explaining the unexplainable: discrepancies in results from the CALGB/SWOG 80405 and FIRE-3 studies.

We propose a working hypothesis that integrates data from the CALGB/SWOG 80405 and FIRE-3 studies to explain apparent discrepancies in their results. Both trials assessed the combination of either cetuximab or bevacizumab with a different chemotherapy backbone: irinotecan in all patients in the FIRE-3 study, or oxaliplatin in 75% of the patients in the CALGB/SWOG 80405 study. The hypothesis is divided into three parts. Firstly, in addition to the biology or microenvironment of the tumour and the selection of the biologically targeted agents common to both trials, chemotherapy itself is an important variable that determines treatment efficacy because of a complex interplay between the biological therapy, the chemotherapy, and the microenvironment. Secondly, the tumour microenvironment, as defined by the Consensus Molecular Subtypes (CMS) classification, determines the interaction of chemotherapeutic agents with biologically targeted agents such as bevacizumab and cetuximab. Whereas irinotecan synergises with cetuximab across all CMS subtypes, oxaliplatin might have variable effects, synergising with cetuximab in fibroblast-poor microenvironments, such as CMS2 and CMS3, but activating fibroblast-rich microenvironments, such as CMS1 and CMS4, to release cytokines that might antagonise some of the cetuximab effects. Thirdly, the previous assumptions integrate into a final concept, which is that overall survival is determined not only by the biological therapy or the first-line treatment, but specifically by the sequence of first-line and second-line regimens, and the degree of synergism between them. In a clinical setting, the optimal first-line combination of biological therapy and chemotherapy predetermines the crossover to a specific second-line treatment, which affects the overall survival of a patient with a specific tumour subtype. Our working hypothesis suggests that the CALGB/SWOG 80405 and FIRE-3 studies are complementary rather than discrepant, and it provides an explanation for their opposing interpretations. In conclusion, proper interpretation of the CALGB/SWOG 80405 and FIRE-3 results requires an in-depth examination of the complex interplay, not only between the targeted biological agents and chemotherapeutic drugs, but also between therapies and the tumour biology and microenvironment, for each line of treatment.

Locally advanced rectal adenocarcinoma: Are preoperative short and long course radiotherapy truly equivalent?

In the neoadjuvant treatment of locally advanced rectal adenocarcinoma, long- and short-course radiotherapy are considered to be of equivalent efficacy based upon several randomized trials. The present study assessed the effect of radiotherapy dose on overall survival. Using the National Cancer Database (2006-2013) 458 individuals with clinical stage II/III rectal adenocarcinoma treated were identified, with either short- (25 Gy) or long- (45 or 50.4 Gy) course neoadjuvant radiotherapy followed by surgery, without neoadjuvant or adjuvant chemotherapy. Multivariate COX regression was employed to evaluate differences in overall survival according to radiotherapy regimen. An association with improved overall survival in individuals treated with long- compared with short-course radiotherapy was demonstrated (HR=0.50, 0.34-0.73). The 30- and 90-day post-surgery mortality rates were higher in the short-course group when compared with the long-course group (12.2 vs. 2.4%; and 18.5 vs. 5.4%, respectively). Following the exclusion of patients that succumbed within 90-days post-surgery, overall survival advantage in the long-course group compared with the short-course group was maintained [hazard ratio (HR)=0.62, 0.39-0.99], with a median overall survival of 25.3 months (IQR 16.9-41.6) for the short-course group compared with 43.5 months (IQR 25.6-67.9) for the long-course group. To the best of our knowledge, the present results suggest for the first time that long-course radiotherapy is associated with an improved overall survival compared with short-course radiotherapy in locally advanced rectal adenocarcinoma in the absence of chemotherapy usage. This possible advantage is clinically relevant mainly in patients who cannot tolerate systemic chemotherapy.

Surgical outcomes of two-stage hepatectomy for colorectal liver metastasis: comparison to a benchmark procedure.

BACKGROUND: Two-stage hepatectomy (TSH) with portal vein embolization (PVE) is associated with high morbidity and mortality and may result in liver failure due to insufficient future liver remnant. The objectives of this investigation were to evaluate the short-term outcomes of patients with colorectal cancer liver metastasis who underwent TSH with PVE, and to critically review the selection criteria for TSH-PVE. METHODS: A retrospective review of all patients who were operated due to bi-lobar CRLM during the years 2007-2017 was performed. Patients who underwent TSH-PVE were compared to those who underwent right hepatectomy (RH) only. RESULTS: Twenty-nine patient underwent TSH, 25 of whom (86.2%) completed both stages. These patients demonstrated a major complication rate of 17%, and a 90-day mortality rate of 3.4%. Most complications (80%) were related to the colonic resection, and one patient developed liver failure. Patients who suffered complications had a trend towards more baseline comorbidities and more liver lesions. Ablative techniques were utilized in 76%. When compared to 35 patients who underwent sole RH, no significant difference was demonstrated in major complication rate (20%) or mortality (0%). CONCLUSIONS: TSH is a relatively safe procedure in selected patients. Ablative techniques can reduce the occurrence of liver insufficiency and should be used liberally when possible. Factors such as number of lesions, comorbidities and the timing of colonic resection should be considered and evaluated in order to improve the outcomes of the procedure.

Refining the Use of Adjuvant Oxaliplatin in Clinical Stage II or III Rectal Adenocarcinoma.

BACKGROUND: Current guidelines include the use of adjuvant oxaliplatin in clinical stage II or III rectal adenocarcinoma. However, its efficacy is supported by a single phase II trial. We aimed to examine whether oxaliplatin confers survival benefit in this patient population. METHODS: Using the National Cancer Database (2006-2013) we identified 6,868 individuals with clinical stage II or III rectal adenocarcinoma treated with neoadjuvant chemoradiotherapy, surgery, and adjuvant chemotherapy. We used multivariate Cox regression to evaluate survival differences according to treatment intensity and change from clinical to pathological stage. RESULTS: We demonstrated an association with improved overall survival with the use of doublet adjuvant chemotherapy in pathological stage III rectal adenocarcinoma (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.67-0.92). This association was confirmed in patients with clinical stage III and subsequent pathological stage III disease (HR, 0.69; 95% CI, 0.57-0.83) and was not observed in patients who progressed from clinical stage II to pathological stage III disease. Doublet adjuvant chemotherapy was not associated with improved overall survival in patients with pathological stage 0 or I disease, regardless of their clinical stage. CONCLUSION: Adjuvant oxaliplatin following neoadjuvant chemoradiotherapy in rectal adenocarcinoma was confirmed in patients with clinical stage III and subsequent pathological stage III disease. Omission of oxaliplatin can be considered in pathological complete response or pathological stage I disease. IMPLICATIONS FOR PRACTICE: Current guidelines include the use of oxaliplatin as part of adjuvant chemotherapy (AC) in patients with clinical stage II or III rectal adenocarcinoma (RAC). However, its efficacy is supported only by a single phase II trial. This study found an association with improved overall survival with the use of doublet AC in patients diagnosed with clinical stage III and subsequent pathological stage III, and not in patients with pathological stage 0 or I, regardless of their clinical stage. Therefore, omission of oxaliplatin can be considered in patients with either pathological complete response or pathological stage I RAC, thereby avoiding oxaliplatin-induced neuropathy.

A new look at the International Duration Evaluation of Adjuvant therapy (IDEA) classification-Defining novel predictive and prognostic markers in stage III colon cancer.

BACKGROUND: The International Duration Evaluation of Adjuvant therapy (IDEA) pooled analysis compared 3 to 6 months of adjuvant chemotherapy for stage III colon cancer. The overarching goal was to reduce chemotherapy-related toxicity, mainly oxaliplatin-induced neuropathy. Patients were classified into low-risk and high-risk groups, suggesting that low-risk patients may be offered only 3 months of treatment. We aimed to evaluate the benefit of monotherapy versus doublet chemotherapy in low and high IDEA risk groups. METHODS: Using the National Cancer Database (2004-2014), we identified 56,728 low-risk and 47,557 high-risk individuals with stage III colon cancer, according to the IDEA classification. We used multivariate Cox regression to evaluate the magnitude of survival differences between IDEA risk groups, according to treatment intensity (doublet versus monotherapy). In a secondary analysis, we examined the prognostic and predictive value of subgroups of age, tumour sidedness and lymph node ratio (LNR). RESULTS: Low and high IDEA risk groups derived similar benefit from doublet adjuvant chemotherapy as compared with monotherapy, with hazard ratios (HRs) of 0.83 (95% confidence interval [CI] 0.79-0.86) and 0.80 (95% CI 0.78-0.83), respectively. The only subpopulations that did not benefit from doublet chemotherapy were low-risk patients older than 72 years (HR = 0.95, 95% CI 0.90-1.01) and high-risk patients older than 85 years (HR = 0.90, 95% CI 0.77-1.05). LNR and tumour sidedness were shown as additional prognostic, but not predictive, factors within the IDEA risk groups. CONCLUSIONS: IDEA risk classification per se does not predict for treatment benefit from doublet chemotherapy in stage III colon cancer. However, omission of oxaliplatin can be considered in IDEA low-risk patients older than 72 years.

Assessing the prognostic value of carcinoembryonic antigen levels in stage I and II colon cancer.

BACKGROUND: Previous studies have shown that elevated preoperative carcinoembryonic antigen (CEA) levels are associated with worse prognosis in patients with colon cancer. These studies compared the prognosis of patients with elevated versus normal CEA levels. We sought to assess the prognostic role of increasing levels of CEA in stage I and II patients who did not receive adjuvant chemotherapy. METHODS: Using the National Cancer Database (2004-2014), we identified 45,449 individuals with stage I and II colon cancer who did not receive adjuvant chemotherapy and had preoperative CEA levels available. We estimated the optimal cut-point of CEA levels to predict survival using the Youden Index. Cox proportional hazards were used to compare individuals with CEA levels above and below the defined cut-point. In a secondary analysis, we examined the prognostic value of stage, age and tumour location. RESULTS: The optimal preoperative CEA cut-point to predict survival was 2.35 ng/mL. The adjusted HR for overall survival among individuals with preoperative CEA levels at or above compared with below 2.35 ng/mL was 1.56 (95% CI, 1.49-1.64). Individuals with CEA levels below 2.35 ng/mL had higher 3-year survival rates compared with those with CEA levels above 2.35 ng/mL (79.7% vs 64.5%, respectively). CONCLUSIONS: Preoperative CEA levels at or above 2.35 ng/mL, found within the normal range, may be used to identify stage I and II colon cancer patients harbouring worse prognosis.