American Society of Clinical Oncology Recommendations on Adjuvant Chemotherapy for Stage II Colon Cancer

Abstract

Direct evidence from randomized controlled trials does not support the routine use of adjuvant chemotherapy for patients with stage II colon cancer. Patients and oncologists who accept the relative benefit in stage III disease as adequate indirect evidence of benefit for stage II disease are justified in considering the use of adjuvant chemotherapy, particularly for those patients with high-risk stage II disease. The ultimate clinical decision should be based on discussions with the patient about the nature of the evidence supporting treatment, the anticipated morbidity of treatment, the presence of high-risk prognostic features on individual prognosis, and patient preferences. Patients with stage II disease should be encouraged to participate in randomized trials.

Factors associated with short recurrence-free survival in completely resected colon cancer

“…Gland formation in less than 50% of the lesion is labeled as Grade III (poorly differentiated), 50–90% gland formation is labeled as Grade II (moderately differentiated), and >90% gland formation is labeled as Grade I (well differentiated) [7]. In contrast to surgical stage, histological grade has no established role in selecting candidates for adjuvant chemotherapy, with the exception of poorly differentiated Stage II CRC patients, among other risk factors, who are considered high risk and could be offered adjuvant chemotherapy [8].…”

Frequent genomic loss at chr16p13.2 is associated with poor prognosis in colorectal cancer

“…2 Although most patients with Stage III (lymph-node positive) cancer receive adjuvant treatment, it is offered to only a subset of Stage II (localized disease) patients presenting with specific high-risk clinical features, including tumor perforation or invasion of adjacent organs. 3 This approach is clearly suboptimal, resulting in undertreatment of $20% of Stage II patients who will recur. Similarly, current adjuvant treatment is clearly ineffective in many Stage III patients, with a recurrence rate of $40% 4,5 highlighting the need for treatment with more aggressive or newly emerging targeted therapies, e.g., inhibitors of epidermal growth factor receptor (EGFR ) and Vascular endothelial growth factor (VEGF), which have been shown to improve survival of patients with metastatic CRC.…”

Serosal surfaces, mucin pools, and deposits, Oh my: challenges in staging colorectal carcinoma

“…It has been suggested by the American Society of Clinical Oncology (ASCO) that the routine use of adjuvant chemotherapy is not recommended for patients with Stage II colon cancer, but there are some patient populations to consider for adjuvant chemotherapy, such as those with inadequately sampled nodes, T4 tumors, bowel perforation, or poorly differentiated histology. 6 The National Comprehensive Cancer Network (NCCN) Guidelines (Version 2.2014) characterize high-risk factors for systemic recurrence as poorly differentiated histology (not MSI-H), lymphatic/vascular invasion, perineural invasion, o12 lymph nodes identified in colon cancer, bowel obstruction, localized perforation, and close, indeterminate or positive margins. Therefore, a patient with a pT3N0 cancer will likely not get adjuvant chemotherapy, while a patient with pT4N0 cancer may be treated with adjuvant chemotherapy.…”