Primary squamous-cell carcinoma of the rectum: report of six cases and review of the literature.

PURPOSE

The majority of colorectal carcinomas diagnosed are adenocarcinomas. Squamous-cell carcinoma is a rare pathologic curiosity. Since 1943, only 18 cases have been described in the medical literature. The aim of this study was to report retrospectively six new cases and to review the medical literature.

PATIENTS

Of the 6 cases, 4 were females, and age ranged from 43 to 93 years. Tumors were located 7 to 12 (mean, 8.5) cm from the anal verge. Five patients underwent surgical resection. Intraoperative radiotherapy was performed in one case. One patient was treated only by external beam radiotherapy. In two cases neoadjuvant combination of external beam radiotherapy and chemotherapy and in one case neoadjuvant contact x-ray treatment were performed. This treatment was followed by external beam radiotherapy in two cases and by chemotherapy in two cases, in patients with lymph node involvement.

RESULTS

The clinical tumor response to radiotherapy was almost complete for the patient who did not undergo surgery. One tumor was sterilized by preoperative radiation. Three patients were alive without recurrence at 6 months, 2 years, and 16 years.

CONCLUSION

The etiopathogenicity of squamous-cell carcinoma of the rectum is discussed. The prognosis of these tumors seems to be worse than that for adenocarcinoma because of a delayed diagnosis. Surgical resection seems to be the most important treatment. Chemotherapy and especially radiotherapy may have some indications.