A Case of Intrapelvic Recurrence of Colonic Carcinoma with Remarkable Prominent Perineural Invasion

Abstract

It is well known that the cancerous invasion into the perineural space is often observed in malignancies of the pancreaticobiliary system. As far as carcinomas of the digestive tract are concerned, however, there have been very few studied so far in Japan. Articles in several western journals have reported perineural invasion in 20 to 30% of whole rectal carcinomas, and that could be the cause of local recurrence and serious pain. In the case presented here the patient had intrapelvic recurrence of colonic carcinoma and developed acute and severe pain in the left thigh and buttock. The recurrent tumor was shown to grow mainly between the bladder and the rectum and to invade the left lateral pelvic wall. Pathological studies following resection showed marked perineural invasion at the periphery of the lesion. Microscopic study of serial sections of the specimen revealed that the distance of invasion into the perineural space reached 1.5 cm from the main tumor margin. This fact suggests that perineural invasion might be one of the major factors of local recurrence of colorectal carcinoma and the cause of pain when recurrence has developed. Careful attention should be paid to the lateral surgical margin at the time of resection and the indications for nerve-preserving surgery should be very strict.