BACKGROUND: Resection of colon cancer with curative intent implies clear margins. An arbitrary requirement of 2 cm DtLM generally ensures surgical and pathological clearance. However, harvest of tumor-draining lymph nodes is related to DtLM. For this reason, an extended longitudinal margin becomes an issue. The major objective of the present study concerns quality development of colon resections, recording the status of DtLM, pT and pN stage, and the pathologists' reporting pattern.

MATERIALS AND METHODS: The study comprised colectomy specimens obtained in 2010 to 2011 at Hvidovre Hospital with documented and suspected carcinoma. Specimens were stratified into 2 groups: DtLM < 5 cm and ≥ 5 cm. Data were correlated with lesional site, surgical approach, pT and pN stage and the pathologists' reporting approach.

RESULTS: DtLM reporting was lacking in 6% of the specimens. DtLM was < 5 cm in 32% of the specimens. Sixty-three and 83.5% of the cancer specimens with DtLM < 5 cm were node-negative and stage pT3/4, respectively, compared with 49% and 87.5% of the ≥ 5 cm counterpart. The difference in percentage distribution of pN stage in the 2 groups was significant, and no significant difference was observed in relation to pT stage.

CONCLUSION: This study suggests that DtLM < 5 cm in colon cancer surgery might result in diagnostic "understaging" and hence leaving metastasis in the patient.