T1 Adenocarcinoma of the Rectum: Transanal Excision or Radical Surgery?

Abstract

Although local excision for rectal cancer has been practiced for more than 120 years, its proper use for the cure of localized rectal cancers is still incompletely understood. The studies on this topic are heterogeneous in terms of selection criteria, surgical approaches and study design. The stage of the disease at the time of diagnosis is the main prognostic factor in rectal cancer. Today the commonly utilized criteria for local excision of rectal cancer are stage T1N0M0, histological grade G1 or G2, and size 3 to 4 cm. Total recurrence rates have been reported to be as low as 0%-4% and as high as 17%-31%. Notwithstanding the differences among the various case series, the risk of recurrence after local excision is real. The evidence seems to point to occult unresected locoregional tumor spread as the major risk factor. We speculate that the combination of unresected occult nodal disease and inadequate adjuvant therapy are two factors that can explain the higher rates of local and distant recurrences. Even radical surgery after the appearance of a recurrence may not be sufficient. When high-risk features are found, patients who return to the operating room immediately for radical surgery have an improved disease-free survival compared to patients who have radical surgery at the time of local recurrence. We conclude that today there is a preference for local excision in older patients in whom radical surgery may be associated with a high risk of complications and death. Local excision in younger and fit patients should be reserved for low-risk cancers in patients who will accept an increased risk of tumor recurrence.