Objective: To assess the relationship between the incidence and prognostic significance of mesorectal involvement.
Methods: 328 cases of rectal cancer resected with total or subtotal mesorectal excision in our hospital from Jan. 1997 to Dec. 1998 were followed up and analyzed in this study. The neoplastic foci were identified at the pathologic examination of the mesorectum.
Results: Neoplastic mesorectal metastasis was found in 234 cases (71.3%); node involvement in 59.8% and microscopic foci involvement in 36% of all cases (isolated in 11.6%, microfoci alone without any kind of other mesorectal involvement). Microscopic deposits were found in 10.3% of TNM Stage I tumors, in 18.4% of Stage II and in 45.1% of Stage III cancers. Five-year disease-free survival rate (49.6% vs. 91.4%) were observed in patients with mesorectal involvement, compared with those without deposits.
Conclusion: The incidence of neoplastic foci in the mesorectum seem to affect prognosis, even in early staged tumors. The presence of mesorectal foci should be considered an index in modifying the conventional staging of the rectal tumor.