Anal cancer with cerebral metastasis: a case report.

Carcinoma of the anal canal is a relatively rare cancer with a low propensity for metastasis. A literature review identifies two cases of brain metastases from anal cancer. The authors present the case of a 63-year-old female with poorly differentiated squamous cell carcinoma of the anal canal who presented with a solitary dural-based enhancing lesion of the right parietal area. The patient underwent craniectomy and tumor resection. Histopathology confirmed the cerebral lesion to be a poorly differentiated squamous cell carcinoma, consistent with the known primary tumor of the anal canal. Although exceptionally rare, the presence of a cerebral lesion in a patient with carcinoma of the anal canal should raise the possibility of metastatic disease. Treatment decisions in patients with newly diagnosed dural-based enhancing lesions and known anal cancer should bear in mind the possibility of metastatic disease.