Primary and recurrent colorectal cancer masquerading as gynaecological malignancy

To make clinicians more aware of the phenomenon of primary and recurrent colorectal and anal carcinoma masquerading as primary gynaecological malignancy, we reviewed the records of 8 women referred to our gynaecological oncology unit with primary colorectal cancer (1), recurrent colorectal cancer (6) and primary anal cancer (1). Seven of these patients presented with abnormal vaginal bleeding or discharge. All patients had Papanicolaou smears performed; 7 were abnormal and 1 unsuitable for cytological assessment. None of the 6 patients with recurrent carcinoma had been previously treated with more than standard anterior or abdominoperineal resection; no radiotherapy had been given, and only 1 patient had received chemotherapy. These patients were treated in our gynaecological oncology unit for their recurrence by surgery and/or chemotherapy and/or irradiation. All 6 had further recurrences in the pelvis despite this aggressive therapy. Follow-up of colorectal cancer in women should involve gynaecological history, pelvirectal examination and Pap smear at each visit. Correct diagnosis of the colorectal origin of a genital tract tumour is made on careful history, examination and biopsy. An abnormal Pap smear may be the first indication of recurrent colorectal cancer in the cervix and vagina, although most patients ultimately present with abnormal vaginal bleeding. The presence of a tumour invading both cervix and posterior vaginal wall is suggestive of spread from a colorectal tumour compared to the more common lateral spread of a cervical primary.