Adjuvant Therapy for Stage II Colon Cancer: ASCO Guideline Update

Use of Circulating Tumor DNA to Guide Decision-making in Adjuvant Colon Cancer

PURPOSE OF REVIEW

The use of circulating tumor DNA (ctDNA) assays to guide clinical decision-making in early-stage colon cancer is an area of rapidly advancing active research. With assays clinically available, clinicians must be informed how to best use this novel tool to treat patients.

RECENT FINDINGS

Recent observational and prospective studies have suggested that ctDNA has potential to guide clinical decision-making in early-stage colon cancer by detecting minimal residual disease (MRD) and predicting recurrence risks. MRD-negative patients may be able to de-escalate or forgo adjuvant chemotherapy (ACT) without compromising disease-free survival or overall survival, while MRD-positive patients may benefit significantly from ACT. Recent and ongoing studies have given reason for optimism about the future of ctDNA as a useful biomarker for clinicians treating early-stage colon cancer. Data thus far are mostly limited to observational studies; inconsistent results highlight the need for caution. As more evidence emerges, ctDNA may become standard of care for colon cancer patients.

A review of trials investigating ctDNA-guided adjuvant treatment of solid tumors: The importance of trial design

Circulating tumor DNA (ctDNA) holds promise as a biomarker for guiding adjuvant treatment decisions in solid tumors. This review systematically assembles ongoing and published trials investigating ctDNA-directed adjuvant treatment strategies. A total of 57 phase II/III trials focusing on ctDNA in minimal residual disease (MRD) detection were identified, with a notable increase in initiation over recent years. Most trials target stage II or III colon/colorectal cancer, followed by breast cancer and non-small cell lung cancer. Trial methodologies vary, with some randomizing ctDNA-positive patients between standard-of-care (SoC) treatment and intensified regimens, while others aim to de-escalate therapy in ctDNA-negative patients. Challenges in trial design include the need for randomized controlled trials to establish clinical utility for ctDNA, ensuring adherence to standard treatment in control arms, and addressing the ethical dilemma of withholding treatment in high-risk ctDNA-positive patients. Longitudinal ctDNA surveillance emerges as a strategy to improve sensitivity for recurrence, particularly in less proliferative tumor types. However, ctDNA as longitudinal marker is often not validated yet. Ultimately, designing effective ctDNA interventional trials requires careful consideration of feasibility, meaningful outcomes, and potential impact on patient care.

Risk Without Reward: Differing Patterns of Chemotherapy Use Do Not Improve Outcomes in Stage II Early-Onset Colon Cancer

PURPOSE

Rising rates of early-onset colon cancer (EOCC) present challenges in deciding how to optimally treat patients. Although standard of care for stage II CC is surgical resection, adding chemotherapy for high-risk disease, evidence suggests treatment selection may differ by age. We investigated whether adjuvant chemotherapy (AC) administration rates differ between patients with early- and later-onset stage II CC.

METHODS

Data originated from the nationwide Flatiron Health electronic health record (EHR)-derived deidentified database spanning January 1, 2003, to August 1, 2021. Adults with stage II CC were grouped as age 18-49 years (EOCC) and those age 50 years or older (later-onset colon cancer [LOCC]). Demographics, Eastern Cooperative Oncology Group score, tumor stage and site, and chemotherapy were included. Primary outcomes included rates of AC administration by age and ethnicity; secondary outcomes included overall survival (OS) and time to metastatic disease (TTMD). Univariate and multivariable logistic regression models evaluated relationships between chemotherapy administration, age, and ethnicity, adjusting for significant covariates.

RESULTS

One thousand sixty-five patients were included. Median age of patients with EOCC was 45.0 years versus 69.0 years for patients with LOCC. Adjusted multivariate analysis showed patients with EOCC received AC significantly more often than patients with LOCC. Non-Hispanic patients received AC at significantly lower rates than Hispanic patients in both cohorts. Subanalysis of stage IIA patients showed that patients with EOCC were more likely to receive AC than patients with LOCC. No significant differences in OS or TTMD were observed by age regardless of AC administration in stage II overall; however, patients with stage IIA EOCC receiving AC had significantly longer TTMD than those not receiving AC.

CONCLUSION

AC was given preferentially in stage II EOCC, even in stage IIA, despite deviation from guidelines. This may expose low-risk patients to unnecessary toxicities and suggests bias toward treating younger patients more aggressively, despite unclear evidence for better outcomes.

Colorectal cancer

Despite decreased incidence rates in average-age onset patients in high-income economies, colorectal cancer is the third most diagnosed cancer in the world, with increasing rates in emerging economies. Furthermore, early onset colorectal cancer (age ≤50 years) is of increasing concern globally. Over the past decade, research advances have increased biological knowledge, treatment options, and overall survival rates. The increase in life expectancy is attributed to an increase in effective systemic therapy, improved treatment selection, and expanded locoregional surgical options. Ongoing developments are focused on the role of sphincter preservation, precision oncology for molecular alterations, use of circulating tumour DNA, analysis of the gut microbiome, as well as the role of locoregional strategies for colorectal cancer liver metastases. This overview is to provide a general multidisciplinary perspective of clinical advances in colorectal cancer.

Targeted panel sequencing of pharmacogenes and oncodrivers in colorectal cancer patients reveals genes with prognostic significance

BACKGROUND

Colorectal cancer is still the second leading cause of cancer-related deaths and thus biomarkers allowing prediction of the resistance of patients to therapy and estimating their prognosis are needed. We designed a panel of 558 genes with pharmacogenomics records related to 5-fluorouracil resistance, genes important for sensitivity to other frequently used drugs, major oncodrivers, and actionable genes. We performed a target enrichment sequencing of DNA from tumors and matched blood samples of patients, and compared the results with patient prognosis stratified by systemic adjuvant chemotherapy.

RESULTS

The median number of detected variants per tumor sample was 18.5 with 4 classified as having a high predicted functional effect and 14.5 moderate effect. APC, TP53, and KRAS were the most frequent mutated genes (64%, 59%, and 42% of mutated samples, respectively) followed by FAT4 (23%), FBXW7, and PIK3CA (16% for both). Patients with advanced stage III had more frequently APC, TP53, or KRAS mutations than those in stages I or II. KRAS mutation counts followed an increasing trend with grade (G1 < G2 < G3). The response to adjuvant therapy was worse in carriers of frameshift mutations in APC or 12D variant in KRAS, but none of these oncodrivers had prognostic value. Carriage of somatic mutations in any of the genes ABCA13, ANK2, COL7A1, NAV3, or UNC80 had prognostic relevance for worse overall survival (OS) of all patients. In contrast, mutations in FLG, GLI3, or UNC80 were prognostic in the same direction for patients untreated, and mutations in COL6A3, LRP1B, NAV3, RYR1, RYR3, TCHH, or TENM4 for patients treated with adjuvant therapy. The first association was externally validated. From all germline variants with high or moderate predicted functional effects (median 326 per patient), > 5% frequency and positive Manhattan plot based on 3-year RFS, rs72753407 in NFACS, rs34621071 in ERBB4, and rs2444274 in RIF1 were significantly associated with RFS, OS or both.

CONCLUSIONS

The present study identified several putative somatic and germline genetic events with prognostic potential for colorectal cancer that should undergo functional characterization.

Longitudinal impact of screening colonoscopy on greenhouse gas emissions

BACKGROUND AND AIM

Colonoscopy is the gold-standard screening test for colorectal cancer. However, it has come under scrutiny for its carbon footprint and contribution to greenhouse gas (GHG) emissions compared to other medical procedures. Notwithstanding, screening colonoscopies may have a positive effect on GHG emissions that is unknown. This study estimated the carbon emissions prevented by screening colonoscopies in the U.S.

METHODS

Using the reported number of screening colonoscopies performed annually in the U.S. and the absolute risk reduction (ARR) reported in the NorDICC trial, we calculated the expected minimum number of cancer treatment and surveillance visits prevented through screening based on the cancer stage. The average carbon emission averted per mile traveled was computed using the Environmental Protection Agency's (EPA) GHG equivalencies calculator. The final estimate of carbon emissions averted over a decade by screening colonoscopies performed in one year was determined.

RESULT

6.3 million screening colonoscopies performed in one year prevent 1,134,000 colorectal cancers over a ten-year period. Of these, 38∙3% (434,254) are localized, 38∙8% (440,281) are regional, and 22∙9% (259,465) are metastatic disease. The minimum number of post-diagnosis visits prevented is 11 for stage I, ≥ 21 for stage II, ≥25 for stage III, and ≥ 20 for stage IV disease, comprised of diagnostic, surgical evaluation, chemotherapy, and surveillance visits. The total number of visits prevented by screening is 2,388,397 for stage I, 5,254,421 for stage II, 13,120,369 for stage III, and 9,210,972 for stage IV disease. Approximately 395 million miles of travel and 158,263 metric tons of CO2, equivalent to 177 million pounds of coal burned, 19 billion smartphones charged, or 18 million gallons of gasoline consumed, were saved over ten years through screening.

CONCLUSION

Colorectal cancer screening decreases cancer-related GHG emissions and minimizes the environmental impact of cancer treatment.

Immunohistochemical analysis of tumor budding in stage II colon cancer: exploring zero budding as a prognostic marker

Tumor budding, a biomarker traditionally evaluated using hematoxylin and eosin (H&E) staining, has gained recognition as a prognostic biomarker for stage II colon cancer. Nevertheless, while H&E staining offers valuable insights, its limitations prompt the utilization of pan-cytokeratin immunohistochemistry (IHC). Consequently, this study seeks to evaluate the prognostic significance of tumor budding using IHC in a contemporary cohort of stage II colon cancer patients, aiming to deepen our understanding of this critical facet in cancer prognosis. We conducted a retrospective, population-based cohort study including 493 patients with stage II colon cancer and evaluated tumor budding using IHC, following the H&E-based guidelines proposed by the International Tumor Budding Consensus Conference Group. Correlation between H&E-based and IHC-based tumor budding was assessed using a four-tiered scoring system that included a zero budding (Bd0) category. Survival analyses explored the prognostic significance of tumor budding assessed by IHC and H&E. As expected, IHC-based tumor budding evaluation yielded significantly higher bud counts compared to H&E (p < 0.01). Interestingly, 21 patients were identified with no tumor budding using IHC. This was associated with significantly improved recurrence-free survival (HR = 5.19, p = 0.02) and overall survival (HR = 4.47, p = 0.04) in a multivariate analysis when compared to tumors with budding. The Bd0 category demonstrated a 100% predictive value for the absence of recurrence. In conclusion, IHC-based tumor budding evaluation in stage II colon cancer provides additional prognostic information. The absence of tumor budding is associated with a favorable prognosis and may serve as a potential marker for identifying patients with no risk of recurrence.

Clinical significance of combined tumour-infiltrating lymphocytes and microsatellite instability status in colorectal cancer: a systematic review and network meta-analysis

BACKGROUND

Microsatellite instability (MSI) status and tumour-infiltrating lymphocytes (TIL) are established prognostic factors in colorectal cancer. Previous studies evaluating the combination of TIL and MSI status identified distinct colorectal cancer subtypes with unique prognostic associations. However, these studies were often limited by sample size, particularly for MSI-high (MSI-H) tumours, and there is no comprehensive summary of the available evidence. We aimed to review the literature to compare the survival outcomes associated with the subtypes derived from the integrated MSI-TIL classification in patients with colorectal cancer.

METHODS

In this systematic review and network meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Library without language restrictions, for articles published between Jan 1, 1990, and March 13, 2024. Patient cohorts comparing different combinations of TIL (high or low) and MSI status (MSI or microsatellite stable [MSS]) in patients with surgically resected colorectal cancer were included. Studies were excluded if they focused on neoadjuvant therapy or on other immune markers such as B cells or macrophages. Methodological quality assessment was done with the Newcastle-Ottawa scale; data appraisal and extraction was done independently by two reviewers. Summary estimates were extracted from published reports. The primary outcomes were overall survival, disease-free survival, and cancer-specific survival. A frequentist network meta-analysis was done to compare hazard ratios (HRs) and 95% CI for each outcome. The MSI-TIL subgroups were prognostically ranked based on P-score, bias, magnitude, and precision of associations with each outcome. The protocol is registered with PROSPERO (CRD42023461108).

FINDINGS

Of 302 studies initially identified, 21 studies (comprising 14 028 patients) were included in the systematic review and 19 (13 029 patients) in the meta-analysis. Nine studies were identified with a low risk of bias and the remaining ten had a moderate risk of bias. The MSI-TIL-high (MSI-TIL-H) subtype exhibited longer overall survival (HR 0·45, 95% CI 0·34-0·61; I2=77·7%), disease-free survival (0·43, 0·32-0·58; I2=61·6%), and cancer-specific survival (0·53, 0·43-0·66; I2=0%), followed by the MSS-TIL-H subtype for overall survival (HR 0·53, 0·41-0·69; I2=77·7%), disease-free survival (0·52, 0·41-0·64; I2=61·6%), and cancer-specific survival (0·55, 0·47-0·64; I2=0%) than did patients with MSS-TIL-low tumours (MSS-TIL-L). Patients with the MSI-TIL-L subtype had similar overall survival (0·88, 0·66-1·18; I2=77·7%) and disease-free survival (0·93, 0·69-1·26; I2=61·6%), but a modestly longer cancer-specific survival (0·72, 0·57-0·90; I2=0%) than did the MSS-TIL-L subtype. Results from the direct and indirect evidence were strongly congruous.

INTERPRETATION

The findings from this network meta-analysis suggest that better survival was only observed among patients with TIL-H colorectal cancer, regardless of MSI or MSS status. The integrated MSI-TIL classification should be further explored as a predictive tool for clinical decision-making in early-stage colorectal cancer.

FUNDING

German Research Council (HO 5117/2-2).

Characteristics and outcomes of large (≥5 cm) colonic adenocarcinomas and comparing outcomes of minimally invasive and open surgery for stage I to III disease

BACKGROUND

Colon cancer prognosis is primarily dependent on the stage at diagnosis, but tumor size and location may also impact prognosis. This study aimed to assess the characteristics and outcomes of patients with ≥5 cm colonic adenocarcinomas and compare outcomes of open and minimally invasive surgery for stage I to III large colonic adenocarcinomas.

METHODS

The National Cancer Database (2010-2019) was searched for patients with colonic adenocarcinomas ≥5 cm. Outcomes of patients who underwent minimally invasive surgery or open surgery were compared after propensity-score matching. The primary outcome was 5-year overall survival and, secondarily, hospital stay, surgical margins, and short-term mortality.

RESULTS

A total of 126,959 patients were included (22.1% of all diagnosed adenocarcinomas). 56% of tumors were right-sided, 32.6% were left-sided, and 11.4% were in the transverse colon. Stage IV disease was recorded in 34.6% of patients. Lymphovascular invasion, perineural invasion, and Kirsten rat sarcoma viral oncogene homolog mutations were recorded in 35.7%, 14.9%, and 41.6% of patients. The rate of positive surgical margins was 9.8%. Median hospital stay was 6 (interquartile range: 4-8) days. 30- and 90-day mortality rates were 4.1% and 7.5%, respectively. After matching, 15,228 patients in the open surgery group were matched to a similar number in the minimally invasive surgery group. The minimally invasive surgery group was associated with significantly lower rates of 30- and 90-day mortality, positive surgical margins, shorter hospital stay, and longer median overall survival (110.6 vs 86.6 months, P < .001) than did open surgery.

CONCLUSION

Large colonic adenocarcinomas are mostly right-sided or transverse and present at a more advanced stage with adverse pathologic features. Minimally invasive surgery was associated with better overall survival and short-term benefits when compared with open surgery.

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.

Cabazitaxel-Loaded Thermosensitive Hydrogel System for Suppressed Orthotopic Colorectal Cancer and Liver Metastasis

The treatment of colorectal cancer is always a major challenge in the field of cancer research. The number of estimated new cases of colorectal cancer worldwide in 2020 is 1 148 515, and the estimated number of deaths is 576 858, revealing that mortality accounted for approximately half of the disease incidence. The development of new drugs and strategies for colorectal cancer treatment is urgently needed. Thermosensitive injectable hydrogel PDLLA-PEG-PDLLA (PLEL) loaded with cabazitaxel (CTX) is used to explore its anti-tumor effect on mice with orthotopic colorectal cancer. CTX/PLEL is characterized by a solution state at room temperature and a hydrogel state at physiologic temperature. The excipients MPEG-PCL and PDLLA-PEG-PDLLA have good biocompatibility and biodegradability. The simple material synthesis and preparation process renders this system cost-effective and more conducive to clinical transformation. An orthotopic colorectal cancer model is established by transplantation subcutaneous tumors onto the cecum of mice. According to the results of experiments in vivo, CTX/PLEL significantly inhibits orthotopic colorectal cancer and liver metastasis in mice. The results indicate that CTX/PLEL nanoparticle preparations have high security and excellent anti-tumor effects, and have great application potential in colorectal cancer therapy.

SEOM-GEMCAD-TTD clinical guidelines for the adjuvant treatment of colon cancer (2023)

Colorectal cancer (CRC) has a 5-year overall survival rate of over 60%. The decrease in the rate of metastatic disease is due to screening programs and the population's awareness of healthy lifestyle. Similarly, advancements in surgical methods and the use of adjuvant chemotherapy have contributed to a decrease in the recurrence of resected disease. Before evaluating a patient's treatment, it is recommended to be discussed in a multidisciplinary tumor board. In stage II tumors, the pathologic characteristics of poor prognosis must be known (T4, number of lymph nodes analyzed less than 12, lymphovascular or perineural invasion, obstruction or perforation, poor histologic grade, presence of tumor budding) and it is mandatory to determine the MSI/MMR status for avoiding administering fluoropyridimidines in monotherapy to patients with MSI-H/dMMR tumors. In stage III tumors, the standard treatment consists of a combination of fluoropyrimidine (oral or intravenous) with oxaliplatin for 6 months although the administration of CAPOX can be considered for 3 months in low-risk tumors. Neoadjuvant treatment is not consolidated yet although immunotherapy is achieving very good preliminary results in MSI-H patients. The use of ctDNA to define the treatment and monitoring of resected tumors is only recommended within studies. These guidelines are intended to help decision-making to offer the best management of patients with non-metastatic colon cancer.

Current Applications and Future Directions of Circulating Tumor Cells in Colorectal Cancer Recurrence

The ability to predict or detect colorectal cancer (CRC) recurrence early after surgery enables physicians to apply appropriate treatment plans and different follow-up strategies to improve patient survival. Overall, 30-50% of CRC patients experience cancer recurrence after radical surgery, but current surveillance tools have limitations in the precise and early detection of cancer recurrence. Circulating tumor cells (CTCs) are cancer cells that detach from the primary tumor and enter the bloodstream. These can provide real-time information on disease status. CTCs might become novel markers for predicting CRC recurrence and, more importantly, for making decisions about additional adjuvant chemotherapy. In this review, the clinical application of CTCs as a therapeutic marker for stage II CRC is described. It then discusses the utility of CTCs for monitoring cancer recurrence in advanced rectal cancer patients who undergo neoadjuvant chemoradiotherapy. Finally, it discusses the roles of CTC subtypes and CTCs combined with clinicopathological factors in establishing a multimarker model for predicting CRC recurrence.

Predictive value of preoperative routine examination for the prognosis of patients with pT2N0M0 or pT3N0M0 colorectal cancer

BACKGROUND

In recent years, the incidence of colorectal cancer (CRC) has been increasing. With the popularization of endoscopic technology, a number of early CRC has been diagnosed. However, despite current treatment methods, some patients with early CRC still experience postoperative recurrence and metastasis.

AIM

To search for indicators associated with early CRC recurrence and metastasis to identify high-risk populations.

METHODS

A total of 513 patients with pT2N0M0 or pT3N0M0 CRC were retrospectively enrolled in this study. Results of blood routine test, liver and kidney function tests and tumor markers were collected before surgery. Patients were followed up through disease-specific database and telephone interviews. Tumor recurrence, metastasis or death were used as the end point of study to find the risk factors and predictive value related to early CRC recurrence and metastasis.

RESULTS

We comprehensively compared the predictive value of preoperative blood routine, blood biochemistry and tumor markers for disease-free survival (DFS) and overall survival (OS) of CRC. Cox multivariate analysis demonstrated that low platelet count was significantly associated with poor DFS [hazard ratio (HR) = 0.995, 95% confidence interval (CI): 0.991-0.999, P = 0.015], while serum carcinoembryonic antigen (CEA) level (HR = 1.008, 95%CI: 1.001-1.016, P = 0.027) and serum total cholesterol level (HR = 1.538, 95%CI: 1.026-2.305, P = 0.037) were independent risk factors for OS. The cutoff value of serum CEA level for predicting OS was 2.74 ng/mL. Although the OS of CRC patients with serum CEA higher than the cutoff value was worse than those with lower CEA level, the difference between the two groups was not statistically significant (P = 0.075).

CONCLUSION

For patients with T2N0M0 or T3N0M0 CRC, preoperative platelet count was a protective factor for DFS, while serum CEA level was an independent risk factor for OS. Given that these measures are easier to detect and more acceptable to patients, they may have broader applications.

Predictive value of preoperative routine examination for the prognosis of patients with pT2N0M0 or pT3N0M0 colorectal cancer

BACKGROUND

In recent years, the incidence of colorectal cancer (CRC) has been increasing. With the popularization of endoscopic technology, a number of early CRC has been diagnosed. However, despite current treatment methods, some patients with early CRC still experience postoperative recurrence and metastasis.

AIM

To search for indicators associated with early CRC recurrence and metastasis to identify high-risk populations.

METHODS

A total of 513 patients with pT2N0M0 or pT3N0M0 CRC were retrospectively enrolled in this study. Results of blood routine test, liver and kidney function tests and tumor markers were collected before surgery. Patients were followed up through disease-specific database and telephone interviews. Tumor recurrence, metastasis or death were used as the end point of study to find the risk factors and predictive value related to early CRC recurrence and metastasis.

RESULTS

We comprehensively compared the predictive value of preoperative blood routine, blood biochemistry and tumor markers for disease-free survival (DFS) and overall survival (OS) of CRC. Cox multivariate analysis demonstrated that low platelet count was significantly associated with poor DFS [hazard ratio (HR) = 0.995, 95% confidence interval (CI): 0.991-0.999, P = 0.015], while serum carcinoembryonic antigen (CEA) level (HR = 1.008, 95%CI: 1.001-1.016, P = 0.027) and serum total cholesterol level (HR = 1.538, 95%CI: 1.026-2.305, P = 0.037) were independent risk factors for OS. The cutoff value of serum CEA level for predicting OS was 2.74 ng/mL. Although the OS of CRC patients with serum CEA higher than the cutoff value was worse than those with lower CEA level, the difference between the two groups was not statistically significant (P = 0.075).

CONCLUSION

For patients with T2N0M0 or T3N0M0 CRC, preoperative platelet count was a protective factor for DFS, while serum CEA level was an independent risk factor for OS. Given that these measures are easier to detect and more acceptable to patients, they may have broader applications.

Time From Colorectal Cancer Surgery to Adjuvant Chemotherapy: Post Hoc Analysis of the SCOT Randomized Clinical Trial

Importance

The timing of adjuvant chemotherapy after surgery for colorectal cancer and its association with long-term outcomes have been investigated in national cohort studies, with no consensus on the optimal time from surgery to adjuvant chemotherapy.

Objective

To analyze the association between the timing of adjuvant chemotherapy after surgery for colorectal cancer and disease-free survival.

Design, Setting, and Participants

This is a post hoc analysis of the phase 3 SCOT randomized clinical trial, from 244 centers in 6 countries, investigating the noninferiority of 3 vs 6 months of adjuvant chemotherapy. Patients with high-risk stage II or stage III nonmetastatic colorectal cancer who underwent curative-intended surgery were randomized to either 3 or 6 months of adjuvant chemotherapy consisting of fluoropyrimidine and oxaliplatin regimens. Those with complete information on the date of surgery, treatment type, and long-term follow-up were investigated for the primary and secondary end points. Data were analyzed from May 2022 to February 2024.

Intervention

In the post hoc analysis, patients were grouped according to the start of adjuvant chemotherapy being less than 6 weeks vs greater than 6 weeks after surgery.

Main Outcomes and Measures

The primary end point was disease-free survival. The secondary end points were adverse events in the total treatment period or the first cycle of adjuvant chemotherapy.

Results

A total of 5719 patients (2251 [39.4%] female; mean [SD] age, 63.4 [9.3] years) were included in the primary analysis after data curation; among them, 914 were in the early-start group and 4805 were in the late-start group. Median (IQR) follow-up was 72.0 (47.3-88.1) months, with a median (IQR) of 56 (41-66) days from surgery to chemotherapy. Five-year disease-free survival was 78.0% (95% CI, 75.3%-80.8%) in the early-start group and 73.2% (95% CI, 72.0%-74.5%) in the late-start group. In an adjusted Cox regression analysis, the start of adjuvant chemotherapy greater than 6 weeks after surgery was associated with worse disease-free survival (hazard ratio, 1.24; 95% CI, 1.06-1.46; P = .01). In adjusted logistic regression models, there was no association with adverse events in the total treatment period (odds ratio, 0.82; 95% CI, 0.65-1.04; P = .09) or adverse events in the first cycle of treatment (odds ratio, 0.77; 95% CI, 0.56-1.09; P = .13).

Conclusions and Relevance

In this international population of patients with high-risk stage II and stage III colorectal cancer, starting adjuvant chemotherapy more than 6 weeks after surgery was associated with worse disease-free survival, with no difference in adverse events between the groups.

Trial Registration

isrctn.org Identifier: ISRCTN59757862.

Mismatch repair deficiency: how reliable is the two-antibody approach? A national real-life study

AIMS

Traditionally, mismatch repair (MMR) status is determined by a panel of four antibodies (MLH1, PMS2, MSH2, MSH6). If all proteins are retained, cases are MMR proficient (pMMR), while loss of one or more proteins is indicative of MMR deficiency (dMMR). This approach has been challenged in favour of a two-antibody approach, using PMS2 and MSH6 as a first screening. Their retainment is deemed sufficient to declare cases pMMR. In this study we aim to verify the validity of the two-antibody approach.

METHODS AND RESULTS

We performed a nationwide study in colorectal cancer (CRC) and endometrial cancer (EC) diagnosed between 2016 and 2023, including 47,657 patients to evaluate the two-antibody approach. In 0.17% and 0.4% of cases of CRC and EC, respectively, dMMR cases would be missed with the two-antibody approach. Subgroup analyses pointed towards slightly increased miss rates in younger patients (under the age of 50 years) in both groups and identified special subtypes (signet ring cell carcinoma, medullary carcinoma, and mucinous carcinoma in CRC and clear cell carcinoma in EC) with increased miss rates. For these specific subgroups, a low threshold should be used for further testing. In case of ambiguous or heterogeneous staining patterns, four antibodies should be used.

CONCLUSION

In general, the application of a two-antibody MMR testing strategy does not lead to considerable failure of dMMR identification and saves costs.

Outcome of Patients with Locally Advanced Rectal Cancer Pursuing Non-Surgical Strategy in National Cancer Database

BACKGROUND

Survival data on patients with locally advanced rectal cancer (LARC) undergoing non-operative management (NOM) in a real-world setting are lacking.

METHODS

We analyzed LARC patients from the National Cancer Database with the following features: treated between 2010 and 2020, age 18-65 years, Charlson comorbidity index (CCI) ≤ 1, received neoadjuvant multiagent chemotherapy plus radiation ≥ 45 Gray, and underwent surgery or NOM. Patients were stratified into two groups: (A) clinical T1-3 tumors with positive nodes (cT1-3N+) and (B) clinical T4 tumors, N+/- (cT4N+/-). We performed a comparative analysis of overall survival (OS) with NOM versus surgery by the Kaplan-Meier method and propensity score matching. Additionally, a multivariable analysis explored the association between NOM and OS.

RESULTS

NOM exhibited significantly lower OS than surgery in both groups. In cT1-3N+ patients, NOM resulted in a 5-year OS of 73.9% (95% confidence interval [CI] = 69.7-77.6%) versus 84.5% (95% CI = 83.6-85.3%) with surgery (p < 0.001). In the cT4N+/- group, NOM yielded a 5-year OS of 44.5% (95% CI = 37.0-51.8%) versus 72.5% (95% CI = 69.9-74.8%) with surgery (p < 0.001). Propensity score matching and multivariable analyses revealed similar conclusions.

CONCLUSION

Patients with LARC undergoing NOM versus surgery in real-world settings appear to have inferior survival.

Neoadjuvant Immunotherapy in Locally Advanced Mismatch Repair-Deficient Colon Cancer

BACKGROUND

Mismatch repair-deficient (dMMR) tumors can be found in 10 to 15% of patients with nonmetastatic colon cancer. In these patients, the efficacy of chemotherapy is limited. The use of neoadjuvant immunotherapy has shown promising results, but data from studies of this approach are limited.

METHODS

We conducted a phase 2 study in which patients with nonmetastatic, locally advanced, previously untreated dMMR colon cancer were treated with neoadjuvant nivolumab plus ipilimumab. The two primary end points were safety, defined by timely surgery (i.e., ≤2-week delay of planned surgery owing to treatment-related toxic events), and 3-year disease-free survival. Secondary end points included pathological response and results of genomic analyses.

RESULTS

Of 115 enrolled patients, 113 (98%; 97.5% confidence interval [CI], 93 to 100) underwent timely surgery; 2 patients had surgery delayed by more than 2 weeks. Grade 3 or 4 immune-related adverse events occurred in 5 patients (4%), and none of the patients discontinued treatment because of adverse events. Among the 111 patients included in the efficacy analysis, a pathological response was observed in 109 (98%; 95% CI, 94 to 100), including 105 (95%) with a major pathological response (defined as ≤10% residual viable tumor) and 75 (68%) with a pathological complete response (0% residual viable tumor). With a median follow-up of 26 months (range, 9 to 65), no patients have had recurrence of disease.

CONCLUSIONS

In patients with locally advanced dMMR colon cancer, neoadjuvant nivolumab plus ipilimumab had an acceptable safety profile and led to a pathological response in a high proportion of patients. (Funded by Bristol Myers Squibb; NICHE-2 ClinicalTrials.gov number, NCT03026140.).

Multivariable prognostic modelling to improve prediction of colorectal cancer recurrence: the PROSPeCT trial

OBJECTIVE

Improving prognostication to direct personalised therapy remains an unmet need. This study prospectively investigated promising CT, genetic, and immunohistochemical markers to improve the prediction of colorectal cancer recurrence.

MATERIAL AND METHODS

This multicentre trial (ISRCTN 95037515) recruited patients with primary colorectal cancer undergoing CT staging from 13 hospitals. Follow-up identified cancer recurrence and death. A baseline model for cancer recurrence at 3 years was developed from pre-specified clinicopathological variables (age, sex, tumour-node stage, tumour size, location, extramural venous invasion, and treatment). Then, CT perfusion (blood flow, blood volume, transit time and permeability), genetic (RAS, RAF, and DNA mismatch repair), and immunohistochemical markers of angiogenesis and hypoxia (CD105, vascular endothelial growth factor, glucose transporter protein, and hypoxia-inducible factor) were added to assess whether prediction improved over tumour-node staging alone as the main outcome measure.

RESULTS

Three hundred twenty-six of 448 participants formed the final cohort (226 male; mean 66 ± 10 years. 227 (70%) had ≥ T3 stage cancers; 151 (46%) were node-positive; 81 (25%) developed subsequent recurrence. The sensitivity and specificity of staging alone for recurrence were 0.56 [95% CI: 0.44, 0.67] and 0.58 [0.51, 0.64], respectively. The baseline clinicopathologic model improved specificity (0.74 [0.68, 0.79], with equivalent sensitivity of 0.57 [0.45, 0.68] for high vs medium/low-risk participants. The addition of prespecified CT perfusion, genetic, and immunohistochemical markers did not improve prediction over and above the clinicopathologic model (sensitivity, 0.58-0.68; specificity, 0.75-0.76).

CONCLUSION

A multivariable clinicopathological model outperformed staging in identifying patients at high risk of recurrence. Promising CT, genetic, and immunohistochemical markers investigated did not further improve prognostication in rigorous prospective evaluation.

CLINICAL RELEVANCE STATEMENT

A prognostic model based on clinicopathological variables including age, sex, tumour-node stage, size, location, and extramural venous invasion better identifies colorectal cancer patients at high risk of recurrence for neoadjuvant/adjuvant therapy than stage alone.

KEY POINTS

Identification of colorectal cancer patients at high risk of recurrence is an unmet need for treatment personalisation. This model for recurrence, incorporating many patient variables, had higher specificity than staging alone. Continued optimisation of risk stratification schema will help individualise treatment plans and follow-up schedules.

Zebrafish Avatar-test forecasts clinical response to chemotherapy in patients with colorectal cancer

Cancer patients often undergo rounds of trial-and-error to find the most effective treatment because there is no test in the clinical practice for predicting therapy response. Here, we conduct a clinical study to validate the zebrafish patient-derived xenograft model (zAvatar) as a fast predictive platform for personalized treatment in colorectal cancer. zAvatars are generated with patient tumor cells, treated exactly with the same therapy as their corresponding patient and analyzed at single-cell resolution. By individually comparing the clinical responses of 55 patients with their zAvatar-test, we develop a decision tree model integrating tumor stage, zAvatar-apoptosis, and zAvatar-metastatic potential. This model accurately forecasts patient progression with 91% accuracy. Importantly, patients with a sensitive zAvatar-test exhibit longer progression-free survival compared to those with a resistant test. We propose the zAvatar-test as a rapid approach to guide clinical decisions, optimizing treatment options and improving the survival of cancer patients.

Advancing perspectives on the off-label use of anticancer drugs: an updated classification and exploration of categories

To date, the definition that the off-label usage of drugs refers to the unapproved use of approved drugs, which covers unapproved indications, patient populations, doses, and/or routes of administration, has been in existence for many years. Currently, there is a limited frequency and prevalence of research on the off-label use of antineoplastic drugs, mainly due to incomplete definition and classification issues. It is time to embrace new categories for the off-label usage of anticancer drugs. This review provided an insight into an updated overview of the concept and categories of the off-label use of anticancer drugs, along with illustrating specific examples to establish the next studies about the extent of the off-label usage of anticancer drugs in the oncology setting. The scope of the off-label use of current anticancer drugs beyond the previous definitions not only includes off-label uses in terms of indications, patient populations, doses, and/or routes of administration but also off-label use in terms of medication course, combination, sequence of medication, clinical purpose, contraindications scenarios, etc. In addition, the definition of the off-label usage of anticancer drugs should be added to the condition at a given time, and it varies from approval authorities. We presented a new and relatively comprehensive classification, providing extensive analysis and illustrative examples of the off-label usage of antineoplastic drugs for the first time. Such a classification has the potential to promote practical adoption and enhance management strategies for the off-label use of antitumor drugs.

Evaluation of colon cancer prognostic factors by CT and MRI: an up-to-date review

Colorectal cancer (CRC) is a significant global health concern. Prognostication of CRC traditionally relies on the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications, yet clinical outcomes often vary independently of stage. Despite similarities, rectal and colon cancers are distinct in their diagnostic methodologies and treatments, with MRI and CT scans primarily used for staging rectal and colon cancers, respectively. This paper examines the challenges in accurately assessing prognostic factors of colon cancer such as primary tumor extramural extension, retroperitoneal surgical margin (RSM) involvement, extramural vessel invasion (EMVI), and lymph node metastases through preoperative CT and MRI. It highlights the importance of these factors in risk stratification, treatment decisions, and surgical planning for colon cancer patients. Advancements in imaging techniques are crucial for improving clinical management and optimizing patient outcomes, underscoring the necessity for ongoing research to refine diagnostic methods and incorporate novel findings into practice.

Complete Obstruction, a Real Risk Factor: A Comprehensive Study on Obstruction in Stage IIA Colon Cancer With Propensity Score Matching Analysis

MICROABSTRACT

This study evaluates the prognostic significance of obstructions in stage IIA colon cancer, distinguishing between partial and complete obstructions. It employs a retrospective review of 1914 patients with propensity score matching to analyze oncologic outcomes. Findings reveal complete obstruction as a significant risk factor for poorer outcomes, emphasizing the necessity for further research to refine treatment strategies, particularly regarding the efficacy of adjuvant chemotherapy across obstruction types.

BACKGROUND

This study examined the prognostic impact of obstructions in stage IIA colon cancer. The analysis specifically differentiated partial and complete obstructions, analyzing their distinct influences of both on oncologic outcomes.

MATERIALS AND METHODS

A retrospective review was conducted of stage IIA colon cancer cases with the presence of an obstruction. Patients were stratified by whether it was partial or complete based on the severity of obstruction. Propensity score matching was employed to control for confounders.

RESULTS

Among 1914 consecutive patients diagnosed with stage IIA colon cancer, 758 patients (597 patients with partial obstruction, 161 patients with complete obstruction) exhibited obstruction, while 1156 patients had no obstruction. The median follow-up period was 126 months. Complete obstruction was associated with poorer disease-free survival (Hazard ratio (HR) = 1.785, P < .001) and overall survival (HR = 1.853, P = .001). This trend persisted after propensity score matching, patients with complete obstruction showing a worsened disease-free survival (HR = 1.666, P = .028) and overall survival (HR = 1.732, P = .041). Adjuvant chemotherapy showed improved outcomes overall, but its efficacy varied across obstruction types.

CONCLUSION

Differentiating between complete and partial obstructions in stage IIA colon cancer is an important clinical distinction, as our findings suggest that complete obstruction is a significant risk factor for poorer oncologic outcomes. While adjuvant chemotherapy generally improves prognosis in stage IIA colon cancer, the correlation of obstruction type with its efficacy remains uncertain, necessitating further research to refine treatment strategies.

Adjuvant chemotherapy in stage 1 colon cancer: Patient characteristics and survival analysis from the national cancer database

BACKGROUND

A subset of patients in ACS-NCDB with stage-1 colon cancer received adjuvant chemotherapy (AC), in contrast to national guidelines. This study aimed to define this population and evaluate associations between AC and survival.

METHODS

Patients with T1-2N0 colon cancer from 2004 to 2016 were separated into AC and non-AC groups. Adverse pathological features (APF) included T2, poor differentiation, lymphovascular invasion, positive margin, and inadequate lymph nodes (<12). Cox proportional hazard models were used to estimate prognostic factors for overall survival (OS).

RESULTS

A total of 1745 of 139,857 patients (1.2 %) received AC. Receiving AC was associated with male sex (p = 0.02), uninsured (p < 0.01), low income (p = 0.02), or having ≥2 APFs (p < 0.001). In the total cohort, AC was associated with increased mortality (HR 1.14 [1.04-1.24] P < 0.01). On subset analysis, AC was associated with improved OS for patients with ≥2 APFs (log-rank P=<0.001), and decreased mortality when adjusted for covariates (HR 0.81 [0.69-0.95] P=<0.01). The most significant predictor of mortality was old age (HR 3.78 [3.67, 3.89] p ≤ 0.01), followed by higher Charlson Comorbidity Index (HR 1.73 [1.69, 1.76] (p ≤ 0.01), and higher APF score (HR 1.46 [1.42, 15.2] p ≤ 0.01).

CONCLUSION

AC was associated with decreased survival in the total cohort of stage 1 colon cancer patients, but was associated with improved survival for patients with multiple APFs.

State-of-the-Art Management of Colorectal Cancer: Treatment Advances and Innovation

Colorectal cancer (CRC) remains a significant global health challenge, ranking among the leading causes of cancer-related morbidity and mortality worldwide. Recent advancements in molecular characterization have revolutionized our understanding of the heterogeneity within colorectal tumors, particularly in the context of tumor sidedness. Tumor sidedness, referring to the location of the primary tumor in either the right or left colon, has emerged as a critical factor influencing prognosis and treatment responses in metastatic CRC. Molecular underpinnings of CRC, the impact of tumor sidedness, and how this knowledge guides therapeutic decisions in the era of precision medicine have led to improved outcomes and better quality of life in patients. The emergence of circulating tumor DNA as a prognostic and predictive tool in CRC heralds promising advancements in the diagnosis and monitoring of the disease. This innovation facilitates better patient selection for exploration of additional treatment options. As the field progresses, with investigational agents demonstrating potential as future treatments for refractory metastatic CRC, new avenues for enhancing outcomes in this challenging disease are emerging.

Effects of Adjuvant Chemotherapy on Early-onset Stage II Colon Cancer at Different Tumor Sites

OBJECTIVES

Left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC) have shown distinct clinical and prognostic features. We investigated the effect of adjuvant chemotherapy (ACT) on cause-specific survival (CSS) in patients with stage II LSCC and RSCC.

METHODS

Using the Surveillance, Epidemiology and End Results (SEER) database, a cohort of patients with stage II colon cancer, aged between 20 and 49 years was identified. Both Cox proportional hazards regression and Kaplan-Meier survival analysis as well as propensity score matching were used.

RESULTS

Overall, 5633 patients were eligible. Patients with RSCC were more likely to be male, black, and younger, with a poor grade and histologic type, and were more likely to have more regional nodes examined and larger tumor size. After propensity score matching, CSS was significantly superior in patients with RSCC compared to those with LSCC (Hazard Ratio (HR): 0.80, 95% CI: 0.68-0.95, P =0.01). However, no survival benefit was observed for patients with LSCC after ACT (HR: 1.10, 95% CI: 0.90-1.35, P =0.35), and surprisingly, ACT was found to do more harm than good in patients with RSCC (HR: 1.31, 95% CI: 1.05-1.63, P =0.02). Even among patients with high-risk features such as T4 stage and regional nodes examined<12 in both groups, ACT still did not improve CSS except for T4 stage LSCC (HR: 0.65, 95% CI: 0.44-0.97, P =0.02).

CONCLUSIONS

The results of this analysis indicate that the prognosis of RSCC is better than that of LSCC in stage II colon cancer, and ACT did not improve CSS in patients with either LSCC or RSCC. Even in patients with parts of high-risk features, ACT still did not improve CSS, except for T4 stage LSCC.

Emergency and Elective Colorectal Cancer-Relationship between Clinical Factors, Tumor Topography and Surgical Strategies: A Cohort Study

Background and Objectives: The purpose of the study was to analyze the relationships among several clinical factors and also the tumor topography and surgical strategies used in patients with colorectal cancer. Materials and Methods: We designed an analytical, observational, retrospective study that included patients admitted to our emergency surgical department and diagnosed with colorectal cancer. The study group inclusion criteria were: patients admitted during 2020-2022; patients diagnosed with colorectal cancer (including the ileocecal valve); patients who benefited from a surgical procedure, either emergency or elective. Results: In our study group, consisting of 153 patients, we accounted for 56.9% male patients and 43.1% female patients. The most common clinical manifestations were pain (73.2% of the study group), followed by abdominal distension (69.3% of the study group) and absence of intestinal transit (38.6% of the study group). A total of 69 patients had emergency surgery (45.1%), while 84 patients (54.9%) benefited from elective surgery. The most frequent topography of the tumor was the sigmoid colon, with 19.60% of the patients, followed by the colorectal junction, with 15.68% of the patients, and superior rectum and inferior rectum, with 11.11% of the patients in each subcategory. The most frequent type of procedure was right hemicolectomy (21.6% of the study group), followed by rectosigmoid resection (20.9% of the study group). The surgical procedure was finished by performing an anastomosis in 49% of the patients, and an ostomy in 43.1% of the patients, while for 7.8% of the patients, a tumoral biopsy was performed. Conclusions: Colorectal cancer remains one of the most frequent cancers in the world, with a heavy burden that involves high mortality, alterations in the quality of life of patients and their families, and also the financial costs of the medical systems.

Survival Outcomes in Patients with Monobloc-Resected Stage IIC (pT4bN0) Colon Cancer: A Retrospective Observational Cohort Study

BACKGROUND

Stage II colon cancer (CC) exhibits considerable prognostic heterogeneous. Our objective was to assess survival but also the prognosis impact of microsatellite instability (MSI) in patients with stage IIC (T4bN0M0) CC.

PATIENTS AND METHODS

We conducted a retrospective observational study including all patients who had primary stage IIC CC resection between 2010 and 2020 in 2 expert centers. The primary endpoint was overall survival (OS) and disease-free survival (DFS) and time-to-relapse (TTR) were secondary endpoints.

RESULTS

Sixty-six patients, median age of 74 years [30-95], were included, with 37.9% presenting MSI (n = 25). Organ invasion involved the last ileal loop (n = 17), another colonic segment (n = 15), omentum (n = 13), visceral peritoneum (n = 13), and the bladder (n = 4). Surgical quality criteria showed complete monobloc resection in all patients and 93.9% R0 resection. After a median follow-up of 5 years [3.5-6.6], the entire population showed a 5-year OS of 65.2% [53.0-80.3] and 5-year DFS of 53.5% [41.1-69.6], with 18.9% [6.8-29.4] experiencing relapses at 5 years. The MSI phenotype correlated with improved 5-year OS (75.5% [56.5-100] vs. 59.5% [44.9-79.0], HR 0.41 [0.17-0.99]; P = .04), but DFS and TTR did not differ. Adjuvant chemotherapy was administered to 34.9% of patients. Univariate analysis identified age > 65 years, MSI status, and the number of nodes as factors associated with OS.

CONCLUSION

These data underline, in relation to a low rate of relapse, the lack of consensus regarding the appropriate indication for adjuvant chemotherapy in this high-risk stage II population.

Budget Impact Analysis of Circulating Tumor DNA Testing for Colon Cancer in Commercial Health and Medicare Advantage Plans

Importance

In a randomized clinical trial, treatment guided by tumor-informed circulating tumor (ct)DNA testing reduced adjuvant chemotherapy use without compromising recurrence-free survival in patients with stage II colon cancer. The potential effects of adopting ctDNA testing into routine patient care is unknown.

Objective

To compare the total cost of patient care scenarios with and without the adoption of ctDNA testing.

Design, Setting, and Participants

This budget impact analysis was conducted from the perspectives of US commercial health and Medicare Advantage payers. A decision-analytical model was populated with age-specific incidence of colon cancer, use of adjuvant chemotherapy, and use of single-agent or multiagent regimens. Total cost was estimated with the costs of ctDNA testing, drug acquisition, administration, surveillance, and adverse events. The analysis was conducted from September 2023 to January 2024.

Exposures

The adoption of ctDNA testing.

Main Outcomes and Measures

The incremental cost in the first year following the adoption of ctDNA testing, where testing will affect patient treatment and costs.

Results

In hypothetical plans with 1 million individuals covered, 35 commercial health plan members and 102 Medicare Advantage members aged 75 years and younger were eligible for ctDNA testing. In the base case with a 50% adoption rate, total cost savings were $221 684 (equivalent to $0.02 per member per month [PMPM]) for a commercial payer and $116 720 (equivalent to $0.01 PMPM) for a Medicare Advantage payer. Cost savings were robust to variations in assumptions of all parameters in the commercial population but sensitive to variations in assumptions of adjuvant chemotherapy use rates in the Medicare Advantage population. The number needed to test to avoid 1 patient receiving adjuvant chemotherapy was 4 in the commercial population and 10 in the Medicare Advantage population. The budget-neutral cost for ctDNA testing was $16 202 for a commercial payer and $5793 for a Medicare Advantage payer.

Conclusions and Relevance

Use of tumor-informed ctDNA testing to guide adjuvant chemotherapy in postsurgery patients with stage II colon cancer was projected to result in cost savings for both commercial and Medicare Advantage payers. Adoption of ctDNA testing is therefore advantageous from a budgetary perspective.

Improved Risk-Stratification Scheme for Mismatch-Repair Proficient Stage II Colorectal Cancers Using the Digital Pathology Biomarker QuantCRC

PURPOSE

There is a need to improve current risk stratification of stage II colorectal cancer to better inform risk of recurrence and guide adjuvant chemotherapy. We sought to examine whether integration of QuantCRC, a digital pathology biomarker utilizing hematoxylin and eosin-stained slides, provides improved risk stratification over current American Society of Clinical Oncology (ASCO) guidelines.

EXPERIMENTAL DESIGN

ASCO and QuantCRC-integrated schemes were applied to a cohort of 398 mismatch-repair proficient (MMRP) stage II colorectal cancers from three large academic medical centers. The ASCO stage II scheme was taken from recent guidelines. The QuantCRC-integrated scheme utilized pT3 versus pT4 and a QuantCRC-derived risk classification. Evaluation of recurrence-free survival (RFS) according to these risk schemes was compared using the log-rank test and HR.

RESULTS

Integration of QuantCRC provides improved risk stratification compared with the ASCO scheme for stage II MMRP colorectal cancers. The QuantCRC-integrated scheme placed more stage II tumors in the low-risk group compared with the ASCO scheme (62.5% vs. 42.2%) without compromising excellent 3-year RFS. The QuantCRC-integrated scheme provided larger HR for both intermediate-risk (2.27; 95% CI, 1.32-3.91; P = 0.003) and high-risk (3.27; 95% CI, 1.42-7.55; P = 0.006) groups compared with ASCO intermediate-risk (1.58; 95% CI, 0.87-2.87; P = 0.1) and high-risk (2.24; 95% CI, 1.09-4.62; P = 0.03) groups. The QuantCRC-integrated risk groups remained prognostic in the subgroup of patients that did not receive any adjuvant chemotherapy.

CONCLUSIONS

Incorporation of QuantCRC into risk stratification provides a powerful predictor of RFS that has potential to guide subsequent treatment and surveillance for stage II MMRP colorectal cancers.

Precision Medicine in the Era of Genetic Testing: Microsatellite Instability Evolved

The recognized importance of microsatellite instability (MSI) in cancer has evolved considerably in the past 30 years. From its beginnings as a molecular predictor for Lynch syndrome, MSI first transitioned to a universal screening test in all colorectal and endometrial cancers, substantially increasing the identification of patients with Lynch syndrome among cancer patients. More recently, MSI has been shown to be a powerful biomarker of response to immune checkpoint blockade therapy across a diversity of tumor types, and in 2017 was granted Food and Drug Administration approval as the first tumor histology-agnostic biomarker for a cancer therapy. Focusing on colorectal cancer specifically, immune checkpoint blockade therapy has been shown to be highly effective in the treatment of both MSI-high (MSI-H) colon and rectal cancer, with data increasingly suggesting an early role for immune checkpoint blockade therapy in MSI-H colorectal tumors in the neoadjuvant setting, with the potential to avoid more toxic and morbid approaches using traditional chemotherapy, radiation therapy, and surgery. The success of MSI as an immune checkpoint blockade target has inspired ongoing vigorous research to identify new similar targets for immune checkpoint blockade therapy that may help to one day expand the reach of this revolutionary cancer therapy to a wider swath of patients and indications.

Principles of risk assessment in colon cancer: immunity is key

In clinical practice, the administration of adjuvant chemotherapy (ACT) following tumor surgical resection raises a critical dilemma for stage II colon cancer (CC) patients. The prognostic features used to identify high-risk CC patients rely on the pathological assessment of tumor cells. Currently, these factors are considered for stratifying patients who may benefit from ACT at early CC stages. However, the extent to which these factors predict clinical outcomes (i.e. recurrence, survival) remains highly controversial, also uncertainty persists regarding patients' response to treatment, necessitating further investigation. Therefore, an imperious need is to explore novel biomarkers that can reliably stratify patients at risk, to optimize adjuvant treatment decisions. Recently, we evaluated the prognostic and predictive value of Immunoscore (IS), an immune digital-pathology assay, in stage II CC patients. IS emerged as the sole significant parameter for predicting disease-free survival (DFS) in high-risk patients. Moreover, IS effectively stratified patients who would benefit most from ACT based on their risk of recurrence, thus predicting their outcomes. Notably, our findings revealed that digital IS outperformed the visual quantitative assessment of the immune response conducted by expert pathologists. The latest edition of the WHO classification for digestive tumor has introduced the evaluation of the immune response, as assessed by IS, as desirable and essential diagnostic criterion. This supports the revision of current cancer guidelines and strongly recommends the implementation of IS into clinical practice as a patient stratification tool, to guide CC treatment decisions. This approach may provide appropriate personalized therapeutic decisions that could critically impact early-stage CC patient care.

Unraveling the role of tumor sidedness in prognosis of stage II colon cancer

Background

Stage II colon cancer has varying risks for metastasis, and treatment strategies depend on molecular and clinicopathological features. While tumor-sidedness is a well-accepted prognostic factor for stage III/IV colon cancer, its role in stage II is controversial. Understanding its effect in stage II is crucial for improving treatment strategies.

Methods

We analyzed clinical and follow-up data of colon cancer from the Surveillance, Epidemiology, and End Results database (2004-2017). Patients were divided into a primary study cohort (2010-2017) and a validation cohort (2004-2009). The baseline characteristics between right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups were compared. Moreover, the effect of tumor size on cancer-specific survival (CSS) was evaluated using Kaplan-Meier analysis.

Results

The study involved 87,355 patients in the study cohort and 65,858 in the validation cohort. Of the study cohort, 52.3% were diagnosed with RCC. The median age was 64 years old, with 48.5% females and 76.8% of white people. In addition, stage II RCC showed better CSS compared with LCC (5-year CSS 88.0% vs 85.5%, P < 0.001), while stage III/IV RCC demonstrated poorer outcomes. Multivariate Cox regression analysis identified that the right-sidedness was a positive prognostic factor in stages I/II but negative in stages III (HR 1.10, P < 0.001) and IV (HR 1.26, P < 0.001). Chemotherapy rates decreased in RCC, particularly in stage II (RCC vs LCC: 16.2% vs 28.5%, P < 0.001). Subgroup analysis, stratified by T3/T4 stages and chemotherapy status, further highlighted better survival outcomes in RCC.

Conclusions

RCC is associated with a significantly better prognosis in stage II. The importance of considering tumor-sidedness in clinical decision-making and the design of future clinical trials should be emphasized.

The depth of perineural invasion is an independent prognostic factor for stage II colorectal cancer

BACKGROUND

Perineural invasion (PNI) is the invasion of nerves by cancer cells and is associated with poor survival in stage II colorectal cancer. However, PNI can be further subdivided according to the depth of invasion, and the depth of PNI has not been clearly linked to prognosis.

METHOD

This study aimed to assess the prognostic value of different depths of PNI in stage II colorectal cancer. We defined PNI in the submucosal plexus and myenteric plexus as superficial perineural invasion (sup-PNI) and PNI in the subserous plexus as deep perineural invasion (deep-PNI). Patients were divided into three groups based on the depth of PNI: sup-PNI, deep-PNI and non-PNI. Then, univariate and multivariate Cox regression analyses were conducted to evaluate the role of PNI in the prognosis of stage II colorectal cancer.

RESULTS

This study enrolled 3508 patients with stage II colorectal cancer who underwent resection for primary colorectal lesions between January 2013 and September 2019. Clinicopathological features, including elevated carcinoembryonic antigen (CEA) levels, T4 stage, poor differentiation, deficient DNA mismatch repair (dMMR), and vascular invasion, were correlated with deep-PNI. Multivariate analyses revealed that deep-PNI was associated with worse overall survival (OS; hazard ratio [HR], 3.546; 95% confidence interval [CI], 2.307-5.449; P < 0.001) and disease-free survival (DFS; HR, 2.921; 95% CI, 2.032-4.198; P < 0.001), compared with non-PNI. Conversely, no significant difference in OS or DFS was observed between the sup-PNI and non-PNI groups in multivariate analyses.

CONCLUSIONS

The study demonstrated that the depth of PNI was an independent prognostic factor for patients with stage II colorectal cancer, and patients with deep PNI had a worse prognosis. Thus, patients with PNI require further subdivision according to the depth of invasion.

The prognostic value of tumor budding in a thoroughly characterized stage II colon cancer population in the context of a national screening program

Tumor budding as a prognostic marker in colorectal cancer has not previously been investigated in a cohort of screened stage II colon cancer patients. We assessed the prognostic significance of tumor budding in a thoroughly characterized stage II colon cancer population comprising surgically resected patients in the Region of Southern Denmark from 2014 to 2016. Tumors were re-staged according to the 8th edition of UICC TNM Classification, undergoing detailed histopathological evaluation and tumor budding assessment following guidelines from the International Tumor Budding Consensus Conference. Prognostic evaluation utilized Kaplan-Meier curves, log-rank tests, and Cox proportional hazard models for time to recurrence (TTR), recurrence-free survival (RFS), and overall survival (OS). Out of 497 patients, 20% were diagnosed through the national colorectal cancer screening program. High-grade tumor budding (Bd3) was found in 19% of tumors and was associated with glandular subtype, perineural invasion, mismatch repair proficient tumors, and tumor recurrence (p < 0.001, p < 0.001, p = 0.045, and p = 0.007 respectively). In multivariable Cox regression, high-grade budding was a significant prognostic factor for TTR compared to low-grade (Bd3 HR 2.617; p = 0.007). An association between tumor budding groups and RFS was observed, and the difference was significant in univariable analysis for high-grade compared to low-grade tumor budding (Bd3 HR 1.461; p = 0.041). No significant differences were observed between tumor budding groups and OS. High-grade tumor budding is a predictor of recurrence in a screened population of patients with stage II colon cancer and should be considered a high-risk factor in a shared decision-making process when stratifying patients to adjuvant chemotherapy.

Double Negativity of MRI-Detected and Pathologically-Diagnosed Extramural Venous Invasion is a Favorable Prognostic Factor for Rectal Cancer

BACKGROUND

Extramural venous invasion (EMVI) is a prognostic factor in rectal cancer. There are two types: EMVI detected by magnetic resonance imaging (MRI) (mr-EMVI) and EMVI detected by pathology (p-EMVI). They have been separately evaluated, but they have not yet been concurrently evaluated. We therefore evaluate both mr-EMVI and p-EMVI in rectal cancer at the same time and clarify their association with prognosis.

PATIENTS AND METHODS

Included were the 186 consecutive patients who underwent complete radical resection of tumors ≤ stage III at Wakayama Medical University Hospital, Japan, between 2010 and 2018. All underwent preoperative MRI examination, and were reassessed for EMVI by a radiologist. Surgically resected specimens were then reassessed for EMVI by a pathologist. We assessed the correlation between positivity of mr-EMVI and p-EMVI and prognosis, and the clinicopathological background behind them.

RESULTS

Patients with double negativity for mr-EMVI and p-EMVI had better prognosis than patients with mr-EMVI or p-EMVI positivity (p < 0.0001). Positivity for mr-EMVI or p-EMVI was a poor independent prognostic factor in multivariate analysis.

CONCLUSIONS

Combined analysis of mr-EMVI and p-EMVI may enable prediction of postoperative prognosis of rectal cancer. Patients with double negativity of mr-EMVI and p-EMVI had better prognosis than patients with some form of positivity. Stated differently, patients with positivity of mr-EMVI, p-EMVI, or both had a poorer prognosis than those with double negativity. Postoperative adjuvant chemotherapy may improve poor prognosis. Combined evaluation of mr-EMVI and p-EMVI may be used to predict clinical outcomes and may be an effective prognostic predictor of rectal cancer.

Notoginsenoside Ft1 inhibits colorectal cancer growth by increasing CD8+ T cell proportion in tumor-bearing mice through the USP9X signaling pathway

The management of colorectal cancer (CRC) poses a significant challenge, necessitating the development of innovative and effective therapeutics. Our research has shown that notoginsenoside Ft1 (Ng-Ft1), a small molecule, markedly inhibits subcutaneous tumor formation in CRC and enhances the proportion of CD8+ T cells in tumor-bearing mice, thus restraining tumor growth. Investigation into the mechanism revealed that Ng-Ft1 selectively targets the deubiquitination enzyme USP9X, undermining its role in shielding β-catenin. This leads to a reduction in the expression of downstream effectors in the Wnt signaling pathway. These findings indicate that Ng-Ft1 could be a promising small-molecule treatment for CRC, working by blocking tumor progression via the Wnt signaling pathway and augmenting CD8+ T cell prevalence within the tumor environment.

Results from the UNITED study: a multicenter study validating the prognostic effect of the tumor-stroma ratio in colon cancer

BACKGROUND

The TNM (tumor-node-metastasis) Evaluation Committee of Union for International Cancer Control (UICC) and College of American Pathologists (CAP) recommended to prospectively validate the cost-effective and robust tumor-stroma ratio (TSR) as an independent prognostic parameter, since high intratumor stromal percentages have previously predicted poor patient-related outcomes.

PATIENTS AND METHODS

The 'Uniform Noting for International application of Tumor-stroma ratio as Easy Diagnostic tool' (UNITED) study enrolled patients in 27 participating centers in 12 countries worldwide. The TSR, categorized as stroma-high (>50%) or stroma-low (≤50%), was scored through standardized microscopic assessment by certified pathologists, and effect on disease-free survival (DFS) was evaluated with 3-year median follow-up. Secondary endpoints were benefit assessment of adjuvant chemotherapy (ACT) and overall survival (OS).

RESULTS

A total of 1537 patients were included, with 1388 eligible stage II/III patients curatively operated between 2015 and 2021. DFS was significantly shorter in stroma-high (n = 428) than in stroma-low patients (n = 960) (3-year rates 70% versus 83%; P < 0.001). In multivariate analysis, TSR remained an independent prognosticator for DFS (P < 0.001, hazard ratio 1.49, 95% confidence interval 1.17-1.90). As secondary outcome, DFS was also worse in stage II and III stroma-high patients despite adjuvant treatment (3-year rates stage II 73% versus 92% and stage III 66% versus 80%; P = 0.008 and P = 0.011, respectively). In stage II patients not receiving ACT (n = 322), the TSR outperformed the American Society of Clinical Oncology (ASCO) criteria in identifying patients at risk of events (event rate 21% versus 9%), with a higher discriminatory 3-year DFS rate (stroma-high 80% versus ASCO high risk 91%). A trend toward worse 5-year OS in stroma-high was noticeable (74% versus 83% stroma-low; P = 0.102).

CONCLUSION

The multicenter UNITED study unequivocally validates the TSR as an independent prognosticator, confirming worse outcomes in stroma-high patients. The TSR improved current selection criteria for patients at risk of events, and stroma-high patients potentially experienced chemotherapy resistance. TSR implementation in pathology diagnostics and international guidelines is highly recommended as aid in personalized treatment.

Elevated postoperative carcinoembryonic antigen guides adjuvant chemotherapy for stage II colon cancer: a multicentre cohort retrospective study

Most clinical doctors rely on high-risk factors recommended by guidelines to decide whether to undergo adjuvant chemotherapy for stage II colon cancer. However, these high-risk factors do not include postoperative carcinoembryonic antigen (CEA). This study aims to explore the elevation of postoperative CEA as a risk factor, in addition to other high-risk factors, to guide adjuvant chemotherapy for patients with stage II colon cancer. A retrospective analysis was conducted on stage II colon cancer patients who underwent curative surgery at Yunnan Cancer Hospital and The Sixth Affiliated Hospital of Sun Yat-Sen University from April 2008 to January 2019. Patients were classified into three groups based on high-risk factors recommended by guidelines and postoperative CEA levels: low-risk with normal postoperative CEA, low-risk with elevated postoperative CEA and high-risk. COX regression analysis was used to identify independent prognostic factors affecting patients' recurrence free survival (RFS). The Kaplan-Meier method was used to create the patients' RFS curve. The restricted cubic spline (RCS) curve was used to assess the correlation between postoperative CEA and RFS on a continuous scale. Among 761 patients, there were 444 males (62.01%), with a median [IQR] age of 58.0 (18.0-88.0) years. A group of 425 high-risk patients had a 3-year RFS of 82.2% (95% CI 78.5-86.1%), while a group of 291 low-risk patients had a 3-year RFS of 89.7% (95% CI 86.1-93.5%). There was a statistically significant difference between the two groups (HR 1.83; 95% CI 1.22-2.74; P = 0.0067). Among them, the 3-year RFS of 261 low-risk patients with normal postoperative CEA was 93.6% (95% CI 90.5-96.8%), while the 3-year RFS of 30 low-risk patients with elevated postoperative CEA was 57.3% (95% CI 41.8-71.4%). There was a significant difference compared to the 3-year RFS of 425 high-risk patients (overall log-rank P < 0.0001). The multivariate analysis adjusted by the COX proportional hazards model showed that low-risk patients with elevated postoperative CEA patients (HR 14.95, 95% CI 4.51-49.63, P < 0.0001) was independently associated with a 3-year RFS. The restricted cubic spline model showed that in stage II colon cancer patients with tumor diameter > 1.955 ng/mL, the risk of postoperative recurrence increased with increasing postoperative CEA levels. Patients with elevated postoperative CEA levels have a significantly increased risk of recurrence. They should be included as high-risk factors to guide adjuvant chemotherapy for stage II colon cancer.

Recent Advances in Therapeutic Strategies to Improve Colorectal Cancer Treatment

Colorectal cancer (CRC) is the second-leading cause of cancer-related mortality worldwide. CRC mortality results almost exclusively from metastatic disease (mCRC) for which systemic chemotherapy is often a preferred therapeutic option. Biomarker-based stratification of mCRC enables the use of precision therapy based on individual tumor mutational profiles. Activating mutations in the RAS/RAF/MAPK pathway downstream of EGFR signaling have, until recently, limited the use of EGFR-targeted therapies for mCRC; however, the development of anti-RAS and anti-RAF therapies together with improved strategies to limit compensatory signaling pathways is resulting in improved survival rates in several highly lethal mCRC sub-types (e.g., BRAF-mutant). The use of fluoropyrimidine (FP)-based chemotherapy regimens to treat mCRC continues to evolve contributing to improved long-term survival. Future advances in chemotherapy for mCRC will need to position development relative to the advances made in precision oncology.

The Prognostic Role of Mismatch Repair Status and CDX-2 Expression with Inflammatory Markers and Pathological Risk Factors in Stage II and III Colon Cancer: Multicenter Real-Life Data

OBJECTIVE

Colorectal cancer is common worldwide, and adjuvant treatment's benefit is still controversial. We designed this study to determine the role of MSI and CDX-2 status determined by immunohistochemistry (IHC) combined with the inflammatory markers and pathological parameters in predicting disease recurrence in stage II and III colon cancer.

METHODS

A total of 226 stage II/III colon cancer patients with a median age of 59 years who underwent initial surgery were included in this retrospective study. The pathologic assessment of MSI and CDX-2 was performed twice by immunohistochemistry (IHC) and two different pathologists. No staining/weak staining below 10% of the tumor was accepted as CDX-2 negative, and any MSI clones with weak staining below 10% were accepted as MSI-H. The laboratory parameters were noted at the initial diagnosis.

RESULTS

One hundred twenty-one and 105 patients were diagnosed with stage III and II colon cancer. 58.0% of patients were male, 46 (20.4%) of tumor tissue were MSS, and 17 (7.5%) were CDX-2 negative. One hundred twenty-nine tumors were localized in the right colon. Disease recurrence was significantly correlated with tumor localization, CDX-2 status, stage at diagnosis, and preoperatively median CRP and CEA levels. DFS rates for MSS patients with CDX-2 negative and positive were 36.7% and 98.1%, respectively [p < 0.001]. There was no significant correlation between MSI status and CDX-2 status. MSI status, the presence of adjuvant treatment, and systemic inflammatory markers were not significant prognostic factors for DFS. CDX-2 status [HR:0.08, CI 95% 0.03-0.17, p < 0.001 HR: 1.7, CI 95% 1.1-3.0, p = 0.03], disease stage [HR:2.6, CI 95% 1.43-4.74], and preoperatively CEA levels [HR:4.1 CI 95% 2.18-785, p < 0.001 were independent significant prognostic factors for DFS.

CONCLUSION

CDX-2 loss was an independent prognostic factor for DFS and disease recurrence in early-stage colon cancer. MSS patients with CDX-2 loss had significantly worse survival outcomes, and this might be the reason for deciding on adjuvant chemotherapy.

qRT-PCR analysis of CEACAM5, KLK6, SLC35D3, MUC2 and POSTN in colon cancer lymph nodes-An improved method for assessment of tumor stage and prognosis

One fourth of colorectal cancer patients having curative surgery will relapse of which the majority will die. Lymph node (LN) metastasis is the single most important prognostic factor and a key factor when deciding on postoperative treatment. Presently, LN metastases are identified by histopathological examination, a subjective method analyzing only a small LN volume and giving no information on tumor aggressiveness. To better identify patients at risk of relapse we constructed a qRT-PCR test, ColoNode, that determines levels of CEACAM5, KLK6, SLC35D3, MUC2 and POSTN mRNAs. Combined these biomarkers estimate the tumor cell load and aggressiveness allocating patients to risk categories with low (0, -1), medium (1), high (2) and very high (3) risk of recurrence. Here we present result of a prospective, national multicenter study including 196 colon cancer patients from 8 hospitals. On average, 21 LNs/patient, totally 4698 LNs, were examined by both histopathology and ColoNode. At 3-year follow-up, 36 patients had died from colon cancer or lived with recurrence. ColoNode identified all patients that were identified by histopathology and in addition 9 patients who were undetected by histopathology. Thus, 25% of the patients who recurred were identified by ColoNode only. Multivariate Cox regression analysis proved ColoNode (1, 2, 3 vs 0, -1) as a highly significant risk factor with HR 4.24 [95% confidence interval, 1.42-12.69, P = .01], while pTN-stage (III vs I/II) lost its univariate significance. In conclusion, ColoNode surpassed histopathology by identifying a significantly larger number of patients with future relapse and will be a valuable tool for decisions on postoperative treatment.

Clinical impact of heterogeneously distributed tumor-infiltrating lymphocytes on the prognosis of colorectal cancer

Background

Tumor-infiltrating lymphocytes (TILs) exist in various malignancies, and have been viewed as a promising biomarker to predict the efficacy and outcome of treatment. However, the marked inter- and intra-tumor heterogeneity of TILs has resulted in some confusion regarding their impact on the prognosis of colorectal cancer (CRC).

Methods

In this study, 78 CRC patients were enrolled and the CD3+ and CD8+ TILs densities at the tumor center (TC), the invasive margin (IM) and the tumor stroma (TS) were assessed by immunohistochemical staining. Their associations with clinicopathological features and progression free survival (PFS) were analyzed to evaluate the predictive and prognostic values of TILs.

Results

TILs were mainly distributed along the invasive margin. High density of TILs in tumor center and invasive margin was associated with smaller tumor size (CD3+TILsIM), reduced tumor invasion (CD3+TILsIM), absence of lymph node metastasis (CD3+TILsIM and CD8+TILsTC), earlier stage (CD3+TILsIM and CD8+TILsIM), and lower tumor grade (CD3+TILsIM and CD8+TILsTC). However, stromal TILs were not associated with any clinicopathological features. Kaplan-Meier survival analysis revealed that high densities of TILs always correlated with prolonged patient survival. The pathological N stage, CD3+ TILsIM and CD8+ TILsTC were found to be independent prognostic indicators. Additionally, early-stage CRC patients who developed recurrence after surgery, showed a higher CD3+/CD8+ TILs ratio in invasive margin. In the present study, it was clarified that CD3+ and CD8+ TILs were heterogeneously distributed in tumor tissues of CRC. The increase in intratumoral and peritumoral TILs had been shown to be strongly predictive of improved clinical outcome. More importantly, the immune signatures enabled to stratify early-stage CRC patients with high risk of recurrence, highlighting the prognostic power of TILs.

Effects of tumour budding on adjuvant chemotherapy in colorectal cancer

BACKGROUND

High tumour budding has been indicated as a risk factor of poor survival in colorectal cancer. This study aimed to investigate the impact of tumour budding grades and the use of adjuvant chemotherapy on prognosis in patients with colorectal cancer.

METHODS

This study included consecutive colorectal cancer patients who underwent radical surgery for primary colorectal adenocarcinoma at The Sixth Hospital of Sun Yat-sen University between 2009 and 2019. Tumour budding was assessed based on the recommendations of the International Tumor Budding Consensus Conference using haematoxylin and eosin (H&E)-stained slides with tumour samples. The primary outcome of interest was to correlate tumour budding with disease-free survival and overall survival; the secondary outcome was investigation of the impact of adjuvant therapy on different tumour budding grades. In addition, a subgroup analysis was performed for the effects of lymphocytic infiltration on adjuvant chemotherapy in patients with Bd3.

RESULTS

Of 709 eligible patients, 412 with colorectal cancer were included. According to the International Tumor Budding Consensus Conference, 210 (50.9 per cent), 127 (30.8 per cent) and 75 (18.2 per cent) were classified as low budding (Bd1), intermediate budding (Bd2) and high budding (Bd3) respectively. Patients with Bd1, Bd2 and Bd3 had 5-year disease-free survival rates of 82.9 per cent, 70.1 per cent and 49.3 per cent respectively, and 5-year overall survival rates of 90 per cent, 79.5 per cent and 62.7 per cent respectively (P <0.001). Adjuvant chemotherapy yielded a significant survival benefit in patients with Bd3 (5-year disease-free survival, 65 per cent versus 31.4 per cent, P <0.001; 5-year overall survival, 84.4 per cent versus 63.1 per cent, P <0.001), but not in those with Bd1 or Bd2. In patients with Bd3, the benefit of adjuvant chemotherapy was maintained in those with low, but not high lymphocytic infiltration.

CONCLUSION

High grade of tumour budding was strongly correlated with poorer survival outcomes in colorectal cancer. Patients with Bd3 benefited from adjuvant chemotherapy, with the exclusion of patients with high lymphocytic infiltration.

Lymphoglandular Complex-Like Colorectal Carcinoma-A Series of 20 Colorectal Cases, Including Newly Reported Features of Malignant Behavior

Distinguishing colon carcinoma that is surrounded by well-circumscribed lymphoid tissue from adenomas involving lymphoglandular complexes can be difficult. We assessed a multi-institutional international cohort of 20 colorectal carcinomas with associated prominent lymphoid infiltrates, which we referred to as lymphoglandular complex-like carcinoma (LGCC). We collected clinical and endoscopic features, including lesion size, endoscopic appearance, location, procedure, follow-up, AJCC stage, and mismatch repair status. We recorded the presence of the following histologic features: haphazard gland distribution, gland angulation, gland fusion, solid nest formation, single-cell formation, stromal desmoplasia, presence of lymphovascular invasion and perineural invasion, presence of lamina propria, cytologic atypia as low- or high-grade, presence of goblet cells in the invasive component, and the presence of a surface lesion. Most cases (9 of 13) were described endoscopically as sessile polyps with an average size of 1.56 cm. Most cases (90%) were associated with a surface lesion, of which the majority were tubular adenomas, though a subset was associated with sessile serrated lesions with dysplasia (3 of 18). All cases of LGCC demonstrated haphazard gland distribution and either gland angulation, fusion, or solid nest formation. A portion of cases demonstrated single-cell infiltration (35%) and desmoplasia (50%), and rarely lymphovascular invasion was present (5%). A subset (10%) of cases invaded beyond the submucosa. Deficient mismatch repair was present in 22% (2 of 9) of cases for which it was performed. In cases of colectomy or completion colectomy, nodal metastasis was present in 38% (3 of 8). No cases demonstrated disease recurrence or disease-specific mortality. Overall, LGCC represents an enigmatic subset of carcinomas that is important to distinguish from adenomas involving lymphoglandular complexes due to its varying prognostic outcomes.

Drug Shortages in Oncology: ASCO Clinical Guidance for Alternative Treatments

PURPOSE

To increase awareness, outline strategies, and offer clinical guidance on navigating the complexities of treatment planning amid antineoplastic drug shortages.

METHODS

A multidisciplinary panel of oncologists, ethicists, and patient advocates was assembled to provide rapid clinical guidance to help providers navigate appropriate patient care in cases where rationing or alternative therapies must be considered. The groups of content experts developed general principles for resource allocation during shortages and clinical guidance on alternative therapies for specific disease sites. The recommendations are supported by evidence when available.

RESULTS

A total of 44 volunteers with content expertise formed the Advisory Group that developed general guidance on the prioritization of antineoplastic agents in limited supply. Disease site-specific clinical guidance was then produced by subgroups on the basis of members' specialties and expertise. The majority of alternative treatment options were developed in consideration of cisplatin and carboplatin shortages. All guidance is posted on ASCO's website.

RECOMMENDATIONS

The prioritization of antineoplastic agents in limited supply should be based on specific goals of the therapy where evidence-based medicine has shown survival outcome and life-extending benefit in both early and advanced stages. Recommendations for specific disease sites are presented. While management options vary according to the disease site, alternatives are presented. For settings in which there are no alternatives with comparable efficacy and safety, it is recommended that patients are referred to an area where the necessary drug is available or can be obtained.Additional information is available at asco.org/drug-shortages.

Adjuvant chemotherapy decision-making in stage II colon adenocarcinoma associated with patients' age and high-risk factors

PURPOSE

To clarify whether the combination of age and high-risk factors (HRFs) was preferable for adjuvant chemotherapy (AC) decision-making in patients with stage II colon adenocarcinoma.

METHODS

We conducted a retrospective study analyzing eligible colon cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2017. A nomogram was used to predict patient prognosis. Decision curve analysis (DCA) predicted model clinical benefit. Restricted cubic spline calculated the optimal cut-off value.

RESULTS

A total of 8570 patients with stage II colon adenocarcinoma were included in this study; 25.2% received AC. A nomogram predicting the prognosis of patients with stage II colon adenocarcinoma was constructed with age and HRFs, and scores were assigned to the relevant variables. DCA showed that age combined with HRFs was superior to treatment decision-making based on HRFs alone. Patients were grouped according to their total score with the cut-off value of 100. AC did not significantly improve overall survival (OS) in low-score group (hazard ratios (HRs) 1.01, 95% confidence intervals (CIs) 0.86-1.18, p = 0.918). In high-score group, AC improved 5-year OS by about 7.6% (HR 0.73, 95% CI 0.61-0.88, p = 0.001). And high-score group mainly included patients aged < 50 years with two or more HRFs and patients aged ≥ 50 years with at least one HRF.

CONCLUSION

Age and HRFs could be preferable for determining the group of stage II colon adenocarcinoma patients who would benefit from AC. Patients aged < 50 years with two or more HRFs might be a potential benefit population for AC.

A national evaluation of adjuvant chemotherapy in pT4N0M0 colon cancer from the National Cancer Database

BACKGROUND

T stage is a prognostic biomarker for overall survival in colon cancer and pathologic T4 disease is a high-risk characteristic. Adjuvant chemotherapy is recommended to improve overall survival in pT4N0M0, but compliance with guidelines is unknown. We aimed to evaluate adjuvant chemotherapy use and impact on overall survival in pT4N0M0 colon cancer.

METHODS

The National Cancer Database was reviewed for pT4N0M0 colon adenocarcinomas undergoing curative surgical resection (2010-2017). Cases were stratified into no adjuvant chemotherapy and adjuvant chemotherapy cohorts. Moderated multiple regression assessed factors associated with no AC. Kaplan-Meier and Cox regression assessed overall survival in propensity-score matched cohorts. The main outcome measures were adjuvant chemotherapy use, factors associated with adjuvant chemotherapy, and impact on overall survival.

RESULTS

Of 11 847 cases, 62.4% (n = 7391) received no adjuvant chemotherapy. With private insurance, comorbidities or income do not affect adjuvant chemotherapy use. Medicare cases with a Charlson-Deyo comorbidity index of 0 (odds ratio [OR] = 0.861, 95% confidence interval [CI] = 0.760 to 0.975; P = .019) and Medicare payors with high income (OR = 0.813, 95% CI = 0.690 to 0.959; P = .014) were associated with adjuvant chemotherapy. Medicaid Charlson-Deyo comorbidity index 0 (OR = 1.374, 95% CI = 1.125 to 1.679; P = .002) and uninsured Charlson-Deyo comorbidity index 0 (OR = 1.351, 95% CI = 1.120 to 1.629; P = .002) were associated with no adjuvant chemotherapy. Adjuvant chemotherapy was associated with improved 5-year overall survival (71.7% vs 56.4%; P < .001; adjusted hazard ratio = 0.543, 95% CI = 0.499 to 0.590; P < .001).

CONCLUSION

Although adjuvant chemotherapy is associated with improved overall survival, compliance is low. There is a complex relationship between payor, income, comorbidity, and adjuvant chemotherapy receipt. Medicare patients with no comorbidities or higher income have better adjuvant chemotherapy use. With private insurance, adjuvant chemotherapy compliance is not affected by comorbidities or income, whereas Medicaid and uninsured patients with no comorbidities have poor compliance. Future work could target these disparities for equitable care.

Inadequate Lymph Node Yield: An Inadequate Indication for Adjuvant Chemotherapy in Stage II Colon Cancer

Background

Optimal therapy for stage II colon cancer remains unclear, and national guidelines recommend "consideration" of adjuvant chemotherapy (ACT) in the presence of high-risk features, including inadequate lymph node yield (LNY, <12 nodes). This study aims to determine whether the survival benefit of ACT in stage II disease varies based on the adequacy of LNY.

Methods

We used the National Cancer Database (NCDB) to identify adults who underwent resection for a single primary T3 or T4 colon cancer between 2006 and 2018. Multivariable logistic regression tested for associations between ACT and prespecified demographic and clinical characteristics, including the adequacy of LNY. We used Cox proportional hazards models to assess overall survival and restricted cubic splines to estimate the optimal LNY threshold to dichotomize patients based on overall survival.

Results

Unadjusted 5- and 10-year survival rates were 84% and 75%, respectively, among patients who received ACT and 70% and 50% among patients who did not (log-rank P < 0.01). Inadequate LNY was independently associated with both receipt of ACT (odds ratios, 1.50; P < 0.01) and decreased overall survival [hazard ratio (HR), 1.56; P < 0.01]. ACT was independently associated with improved survival (HR, 0.67; P < 0.01); this effect size did not change based on the adequacy of LNY (interaction P = 0.41). Results were robust to re-analysis with our cohort-optimized threshold of 18 lymph nodes.

Conclusions

Consistent with contemporary guidelines, patients with inadequate LNY are more likely to receive ACT. LNY adequacy is an independent prognostic factor but, in isolation, should not dictate whether patients receive ACT.