Drawing up an individual risk index for development of metachronous neoplastic lesions in resected colorectal cancer

Abstract

Aim: to identify possible risk factors for the development of metachronous lesions in colorectal cancer (CRC) which would allow to establish a post-surgical individual prognostic index.Patients and methods: three hundred eighty-two surgically treated CRC were reviewed. We compared the incidence of metachronous lesions in 40 variables concerning patient clinical data and initial neoplastic findings. An individual risk index for metachronicity was drawn up including those variables which presented significant differences in multivariate logistic regression, dividing patients into three groups.Results: variables with prognostic value for metachronicity were distal cancer location: OR= 2.30 (1.03-5.13), alcohol intake: OR = 2.20 (1.08-4.48), presence of synchronous adenomas: isolated: OR = 2.47 (1.03-4.48), multiple: OR = 4.26 (1.78-10.17), and presence of synchronous advanced adenoma: OR= 2.91 (1.52-12.60). Tumor MUC-5 expression proved to have a protective role: ). An individual risk score was established considering these variables and patients could be classified into three groups, with a discrimination power for metachronicity of p< 0.0000001. Classification in high and low risk groups had a sensitivity = 75.32%, specificity = 84.21%, positive predictive value = 75.34%, negative predictive value = 92.31% and global diagnostic accuracy = 80.75%.Conclusions: the identification of risk factors for the development of metachronous lesions allow to calculate, at the time of surgical treatment, an individual prognostic index and to classify patients into three different risk groups. In high and low risk groups, both specificity and accuracy were acceptable for the prognosis of metachronous lesions, being remarkable the negative predictive power of our classification, which could become relevant when planning a different endoscopic follow up of these patients.Key words: Colorectal cancer. Follow-up. Metachronous lesions. INTRODUCTIONThe majority of colorectal cancers (CRC) are sporadic cases (1,2) and little is known about metachronous or synchronous neoplasms development (3,4). These multicentric lesions could be due to mutations in genes related to apoptosis, cellular proliferation or DNA repairing (5), or forms of hereditary non polyposis colorectal cancer syndrome with low penetrance (6). Finally, this tumor multicentricity could be caused by multiple interacting factors, such as personal or familial predisposition, environmental mechanisms, morphological or immunophenotypical tumor features which would favoured an increased risk of neoplasm development along different colonic sites (7). Once the tumor and all the possible synchronic lesions are endoscopically or surgically resected, the tumor multicentricity might promote the development of new neoplastic lesions (8,9). Similar to synchronous lesions, metachronic neoplasms will be adenomas in most cases and less frequently CRC. There are several publications related to development of metachronous lesions after the resection of the initial polyps in patient...

Risk factors for metachronous adenoma in the residual colon of patients undergoing curative surgery for colorectal cancer

“…This is supported by previous studies which have also demonstrated that both MA and metachronous cancer occur more frequently in patients with a proximal tumour [ 24 , 25 ]. A more recent study, however, has challenged this view by describing a higher rate of MAs in patients with distal tumours and postulated that removal of the right colon protects against development of MAs which usually occur proximal to the primary cancer [ 26 ]. The observed association between proximal tumours and adenomas was previously believed to arise from cases with undiagnosed HNPCC and microsatellite instability (MSI) who are more likely to present with multiple lesions [ 27 , 28 ].…”

Risk of subsequent primary malignancies among patients with prior colorectal cancer: a population-based cohort study

“…The present study confirmed the difference between patients with colon cancer and rectal cancer, and identified a difference between patients with right-sided and left-sided colon cancer. Studies have indicated that the risk for metachronous colorectal tumors is higher in patients with right-sided colon cancer than in those with left-sided colon cancer;16,35,36 how-ever, other studies have indicated that patients with left-sided colon cancer have higher risk 37,38. Based on a detailed classification of primary CRC subsites in the present study, the risk of multiple primary cancers gradually decreased from patients with right-sided colon cancer to those with left-sided colon cancer and to rectal cancer.…”

Colonoscopy surveillance after colorectal cancer resection: recommendations of the US multi-society task force on colorectal cancer

“…47 There were 93 (1.8%) metachronous cancers diagnosed between 7 and 356 months after the initial CRC diagnosis (40.8% diagnosed within 36 months), and these were attributed to missed lesions in 43%, nonadherence to surveillance recommendations in 43%, and incomplete resection in 5.4%; de novo cancers accounted for only 5.4%. Several studies show that patients with CRC and synchronous adenomas or advanced adenomas have a higher risk of developing metachronous adenomas 12,40,42,46,[55][56][57][58][59] and advanced neoplasms, including cancer 40,[56][57][58][59][60][61] after surgery, underscoring the importance of adequate perioperative colonoscopy. The role of CTC in the perioperative setting is discussed in the section "Alternatives and Adjuncts to Colonoscopy," but the case of obstructive CRC precluding preoperative colonoscopy and perioperative clearing done by CTC deserves additional comment.…”