BIPEDAL LYMPHOGRAPHY IN THE MANAGEMENT OF CARCINOMA OF THE ANAL-CANAL

The purpose of this study was to determine the extent of metastatic pe lvic lymph nodes evident on bipedal lymphography in a group of patient s under consideration for combined radiation therapy and chemotherapy as definitive treatment for carcinoma of the anal canal. Lymphography was attempted in 32 patients and successful bilateral cannulation and opacification of nodes was achieved in 28 (88%). Seven patients had ly mphographic evidence of external iliac node metastases (25%). When pat ients were categorized according to the extent of clinically evident d isease at presentation, 0/15 patients with T1/T2 tumours had positive lymphograms whereas 7/13 patients with T3/T4 tumours and/or positive i nguinal or peri-rectal nodes had positive lymphograms (Fisher's exact test p = 0.0015). All patients with a positive lymphogram had undergon e CT scanning of the pelvis and in only one patient was external iliac node involvement detected. In none of these patients was visceral or more extensive nodal metastases discovered. Subsequently, the external iliac nodes with radiological evidence of metastases on lymphography were included in the treatment volume taken to radical dosage. The pro jected cause specific actuarial 5 year survival for this cohort of pat ients is 86% (median follow-up 4 years). Since the prognosis for patie nts who relapse in pelvic nodes is poor. bipedal lymphography is advoc ated as a staging procedure in patients with advanced primary tumours and in all patients with clinically positive inguinal or peri-rectal l ymph nodes who are being considered for curative therapy.