No abstract

An 11-year-old boy presented with a 2-month history of colicky central abdominal pain associated with nausea and occasional vomiting. He had had one episode of a small quantity of fresh rectal bleeding. No abnormality was found on clinical examination of the abdomen and rectum. Sigmoidoscopy to 12 cm was negative. Barium enema examination showed a complete obstruction at the upper part of the descending colon. At laparotomy, a firm tumour mass was found in the upper descending colon, obstructing the lumen, and two smaller masses were present in the transverse colon. Several middle colic and epiploic lymph nodes were abnormally firm. An anterior rectal mass was also present below the peritoneal reflection. The liver was free of metastases. Total colectomy and proximal rectal resection with low iliorectal anastomosis was performed.Histology of the nodules showed the presence of an invasive, moderately poorly differentiated carcinoma in which there was evidence of central mucin secretion ( Figure I). There was a moderate scirrhous reaction surrounding the carcinoma which had the morphological appearances of a carcinoid. The majority of tumour cells were strongly 'Diazo' positive as well as 'Lead' haematoxylin positive. Although all the excision margins were complete, malignant cells were present in the serosal fat and several of the small adjacent lymph nodes were infiltrated by secondary carcinoma.The child had a good early postoperative course. However, at 3-month review he was found to have multiple tumour masses in his abdomen and liver with renal failure as a result of tumour infiltration of his ureters. Resuscitative measures were put in hand but he failed to respond. DiscussionCarcinoid tumours of the colorectum are uncommon. These tumours are of special interest as they arise from the Kulchitsky cells anywhere between the oesophagus and rectum. These chromaffin cells also have an affinity for silver salts but it is noteworthy that only cells within midgut derivatives are truly argentafin. This explains the clinical situation whereby liver metastases of carcinoid tumours arising out of midgut structures may produce the carcinoid syndrome, whereas similar hepatic metastases from tumours of hindgut origin, lacking the argentaffin reaction, fail to do so1. In this case SHIAA levels were normal. * Present address: Western Infirmary, Glasgow, U K Chromafin cells do not appear until the age of four and the concentration of these cells increases slowly over a period of several years' before they degenerate and decrease in the elderly. The average age of patients with colonic carcinoid is around 60 years' and it is rare in children.Prognosis in this condition has to be viewed in the light ofthe site and size of the tumours and evidence of metastases. Colonic carcinoids carry the worst prognosis of all gastrointestinal sites. Tumour size is important, all those greater than 2 cm being regarded as malignant4. Evidence of liver metastases, although unlikely to produce the carcinoid syndrome, carry a very bad prognosis a...