Do Stage I Colorectal Cancers with Lymphatic Invasion Require a Different Postoperative Approach?

Although stage I colorectal cancer has an excellent prognosis after complete surgical resection, disease recurrence still occurs. This study aimed to assess prognostic risk factors in this early stage of disease.

All non-neoadjuvantly treated stage I colon (CC) and rectal (RC) patients who underwent a surgical resection between 2004 and 2015 were identified. Clinicopathological differences and long-term oncological outcomes were compared.

CC patients (n = 433) were older and had more pre-existing comorbidities. RC patients (n = 86) were associated with more T2 tumors, venous invasion, and higher rates of 30-day morbidity. In multivariate analysis, lymphatic invasion was found to be an independent predictor for disease recurrence (OR 4.57, P = 0.010) and worse disease-free survival (HR 4.26, P = 0.012). This was particularly true for distant recurrence, with eight times higher hazard ratios when lymphatic invasion was present (HR 8.02, P < 0.001). T2 tumors were at risk, though no significant association was found (OR 3.86, P = 0.051; HR 3.61, P = 0.065, respectively).

Lymphatic invasion was strongly associated with worse DFS, in particular distant recurrence. This subgroup of stage I patients might benefit from a more intensive follow-up and maybe should be considered for adjuvant therapy.