Risk factors associated with requiring a stoma for the management of anal cancer

Combination chemotherapy and radiation therapy has become the standard of care for epidermoid carcinoma of the anus. This treatment modality has allowed for preservation of the anus in most patients, sparing them the morbidity of a stoma. Some patients will ultimately require a stoma as a result of salvage surgery or to manage complications of chemoradiotherapy. We hypothesized that tumor characteristics and radiation dose had an impact on the requirement for stoma formation.

Data on all patients with epidermoid carcinoma of the anal canal who were treated with chemoradiation with curative intent at Ochsner Clinic Foundation were entered into a prospective registry. We excluded four patients who were lost to follow-up and one patient who died during chemoradiation therapy.

Fifty-one patients were followed for an average of 5.6 years. Primary tumor size average was 3.9 cm. Six patients had Stage I disease, 33 patients had Stage II disease, and 12 patients had Stage III disease (N+ disease). The average radiation dose was 57 +/- 17 Gy. Univariate analysis revealed pretreatment tumor size to be the only significant factor associated with the need for a stoma ( P = 0.01). Radiation dose was not an important factor ( P = 0.38). An additional finding was that the pretreatment tumor size and N+ disease were significant predictors of mortality; however, logistic-regression analysis revealed that N+ disease was the only independent predictor of mortality ( P = 0.02).

Patients who have large tumors on presentation should be made aware of the possibility of requiring salvage surgery to treat persistent or recurrent disease. Toxicities from chemoradiotherapy do arise, but patients are not at increased risk for requiring a stoma.