Inferior mesenteric angiography was carried out in 14 patients with locoregional recurrence following sphincter-saving resection of a colorectal primary tumour in the left hemicolon or rectum. The aim was to check the margins of clearance of the lymphatic drainage. All patients had been operated on electively and with curative intent. All patients had a biopsy-proven recurrence and 11 of the 14 patients (79%) showed residual arteries that should have been resected at primary surgery, and at laparotomy for the recurrence incomplete resection of the lymphatic drainage area was confirmed. In 6 patients the recurrence was resected, in 4 of them with no evidence of microscopic residual disease. From these findings it may be argued that the lymph nodes incompletely resected at primary operation may have been the origin of the locoregional recurrence. Angiography may detect this situation, and may be worthwhile when planning a reintervention.