Polypectomy versus surgery in early colon cancer: size and location of colon cancer affect long-term survival.

BACKGROUND AND AIMS: The colon cancer survival rate is significantly affected by location, stage, and size of the cancer. Polypectomy was shown be as equally effective as surgery in early-stage colon cancer, but there have been no established clinical guidelines in the management of colon cancer based on the size of the polyp or the tumor location. The aim of our study was to assess the early-stage colon cancer-specific survival rate in patients who underwent endoscopic polypectomy versus surgery, based on size and location of tumor in early-stage colon cancer. METHODS: This is a population-based nationwide study in the USA. RESULTS: Of 13,157 patients, 15.5% underwent endoscopic treatment and 84.5% underwent surgical therapy. For early cancer tumors located in the left colon, polypectomy yielded comparable 5-year survivals to surgery irrespective of size of the tumors. Five-year early cancer-specific survivals were similar for tumors located in the right colon that were < 20 mm in size (94.5 vs 94.3%, p value = 0.94). However, tumors > 20 mm in size that were located in the right colon had better survivals when treated surgically compared to those treated with polypectomy (20-39 mm: 91.8 vs 74.2%; ≥ 40 mm: 92.4 vs 60%, both p values < 0.01). Similar results were obtained on propensity score analysis. CONCLUSIONS: Polypectomy was as effective as surgical therapy for small tumors. For larger tumors, surgical therapy is better than polypectomy for right-sided tumors, but both are equally effective for left-sided tumors.

T1 colon cancer in the era of screening: risk factors and treatment.

BACKGROUND: The aim of this study was to identify risk factors for lymph node positivity in T1 colon cancer and to carry out a surgical quality assurance audit. METHODS: The sample consisted of consecutive patients treated for early-stage colon lesions in 15 colorectal referral centres between 2011 and 2014. The study investigated 38 factors grouped into four categories: demographic information, preoperative data, indications for surgery and post-operative data. A univariate and multivariate logistic regression analysis was performed to analyze the significance of each factor both in terms of lymph node (LN) harvesting and LN metastases. RESULTS: Out of 507 patients enrolled, 394 patients were considered for analysis. Thirty-five (8.91%) patients had positive LN. Statistically significant differences related to total LN harvesting were found in relation to central vessel ligation and segmental resections. Cumulative distribution demonstrated that the rate of positive LN increased starting at 12 LN harvested and reached a plateau at 25 LN. CONCLUSIONS: Some factors associated with an increase in detection of positive LN were identified. However, further studies are needed to identify more sensitive markers and avoid surgical overtreatment. There is a need to raise the minimum LN count and to use the LN count as an indicator of surgical quality.

Survival following early-stage colon cancer: an ACCENT-based comparison of patients versus a matched international general population†.

BACKGROUND: Post-treatment survival experience of early colon cancer (CC) patients is well described in the literature, which states that cure is probable for some patients. However, comparisons of treated patients' survival versus that expected from a matched general population (MGP) are limited. PATIENTS AND METHODS: A total of 32 745 patients from 25 randomized adjuvant trials conducted from 1977 to 2012 in 41 countries were pooled. Observed long-term survival of these patients was compared with expected survival matched on sex, age, country, and year, both overall and by stage (II and III), sex, treatment [surgery, 5-fluorouracil (5-FU), 5-FU + oxaliplatin], age (<70 and 70+), enrollment year (pre/post 2000), and recurrence (yes/no). Comparisons were made at randomization and repeated conditional on survival to 1, 2, 3, and 5 years. CC and MGP equivalence was tested, and observed Kaplan-Meier survival rates compared with expected MGP rates 3 years out from each landmark. Analyses were also repeated in patients without recurrence. RESULTS: Within most cohorts, long-term survival of CC patients remained statistically worse than the MGP, though conditional survival generally improved over time. Among those surviving 5 years, stage II, oxaliplatin-treated, elderly, and recurrence-free patients achieved subsequent 3-year survival rates within 5% of the MGP, with recurrence-free patients achieving equivalence. CONCLUSIONS: Conditional on survival to 5 years, long-term survival of most CC patients on clinical trials remains modestly poorer than an MGP, but achieves MGP levels in some subgroups. These findings emphasize the need for access to quality care and improved treatment and follow-up strategies.

Immediate Adjuvant Chemotherapy in Non-Metastatic Colon Cancer: Phase I Trial Evaluating a Novel Treatment Protocol.

BACKGROUND: The optimal timing of adjuvant chemotherapy (AC) in non-metastatic colon cancer is poorly defined. Delays in AC result in decreased survival. Effective cytotoxic treatments should be considered during the perioperative phase of care. The immediate adjuvant chemotherapy (IAC) concept intends to capitalize on the therapeutic benefits that can be achieved in the perioperative period. We aim to demonstrate that IAC is safe and tolerable. PATIENT AND METHODS: Microsatellite stable invasive adenocarcinomas were treated with intravenous Leucovorin 20 mg/m2 and single dose of 5-Flurouracil 400mg/m2 at the time of surgery. High-risk stage II and stage III received the first dose of standard AC at 14 days after surgery. Serial measurements of blood-based biomarkers were measured. Quality of life (QOL) was measured using EORTC QLQ-C30. RESULTS: Of the 20 patients recruited, 40% had final pathology of stage III, 40% stage II and 20% stage I. All patients received intra-operative chemotherapy with no associated morbidity. Median length of stay was 2 days (range of 2-4). There was no intraoperative morbidity with 5% (N = 1) grade 3 complication. AC was administered to 65% of patients. The median time to AC was 14 days (range 14-36). Overall quality of life and health scores were similar before surgery and at 30-day postoperatively (P < .05). CONCLUSIONS: A protocol based on IAC starting at the time of surgical resection was found to be safe and feasible with no adverse effects on surgical morbidity or quality of life. Further prospective studies are needed to explore the oncologic benefit of this novel systemic treatment approach.

Complex Chromosome-Positive Acute Myelogenous Leukemia Identified 16 Months following the Completion of Capecitabine Chemotherapy for Early-Stage Colon Cancer.

Capecitabine is an oral chemotherapy that is used to treat several cancer types, including breast, gastrointestinal, hepatobiliary, and ovarian. The use of antimetabolites in cancer therapy has generally not been associated with leukemogenesis. In this report, we demonstrate a case of capecitabine-related acute myeloid leukemia that was diagnosed 16 months after the completion of treatment for early-stage colon cancer, by a complex chromosome analysis 48,XY,6,del(7)(q22),+8,+13,t(13;17)(q12;p13),t(13,21)(q12;122),+mar [Gazi Med J. 2018 Jan;29(1):57-58]. This is the first report to our knowledge of the development of t-AML in a patient with early-stage colon cancer that was caused by capecitabine. We should use capecitabine with caution. Further studies are essential to investigate capecitabine-triggered leukemogenesis.

The Promise of Circulating Tumor DNA (ctDNA) in the Management of Early-Stage Colon Cancer: A Critical Review.

The current standard treatment for patients with early-stage colon cancer consists of surgical resection, followed by adjuvant therapy in a select group of patients deemed at risk of cancer recurrence. The decision to administer adjuvant therapy, intended to eradicate the clinically inapparent minimal residual disease (MRD) to achieve a cure, is guided by clinicopathologic characteristics of the tumor. However, the risk stratification based on clinicopathologic characteristics is imprecise and results in under or overtreatment in a substantial number of patients. Emerging research indicates that the circulating tumor DNA (ctDNA), a fraction of cell-free DNA (cfDNA) in the bloodstream that originates from the neoplastic cells and carry tumor-specific genomic alterations, is a promising surrogate marker of MRD. Several recent studies suggest that ctDNA-guided risk stratification for adjuvant therapy outperforms existing clinicopathologic prognostic indicators. Preliminary data also indicate that, aside from being a prognostic indicator, ctDNA can inform on the efficacy of adjuvant therapy, which is the underlying scientific rationale for several ongoing clinical trials evaluating ctDNA-guided therapy escalation or de-escalation. Furthermore, serial monitoring of ctDNA after completion of definitive therapy can potentially detect cancer recurrence much earlier than conventional surveillance methods that may provide a critical window of opportunity for additional curative-intent therapeutic interventions. This article presents a critical overview of published studies that evaluated the clinical utility of ctDNA in the management of patients with early-stage colon cancer, and discusses the potential of ctDNA to transform the adjuvant therapy strategies.