Chronic secondary caeco-colic intussusception in a boy associated with primary malignant lymphoma of caecum (a case report).
Intussusception is the most common cause of intestinal obstruction in children under two years of age and the classic triad of colicky abdominal pain, bloody stools, and a palpable mass leads to the correct diagnosis in most cases. However, it is somewhat distressing that the similar presentation with abdominal pain, vomiting and bloody stools in an older child may not result in nearly so prompt a diagnosis leading to delayed or inadequate management of such cases because of lack of suspicion of the correct diagnosis., 
The large bowel intussusception secondary to primary malignant neoplasm of the bowel is extremely rare in children and we could not collect any such previous reports in the Indian literature. On the contrary, frequent association of small bowel ileal lymphosarcoma and intussusception in the older child has been reported occasionally, 
The aim of this communication is to emphasize the fact that:
(i) high index of suspicion is required to avoid unnecessary delay of diagnosis of intussusception in older children,
(ii) the most common pathologic lesion causing intussusception in the ileocaecal region is malignant lymphoma in older children, and
(iii) inadequate surgical management may result from failure to recognise the relationship between intussusception and malignant lymphoma in the older child.
A 6 year old male child was admitted with the chief complaints of recurrent, intermittent, colicky pain in the abdomen, vomiting, abdominal distention and constipation of 2 months' duration. There was history of a reddish mass coming out per rectum intermittently that used to bleed. The patient had elsewhere a few evacuation enemas without any success.
On examination, the child was sick, ill-looking, pale, emaciated with signs of mild dehydration and tachycardia. Per-abdominal examination revealed moderately distended, non-tender abdomen with visible peristalsis. A firm mildly tender tubular mass with limited mobility and conforming to the contours of descending colon and sigmoid colon was felt in the left iliac fossa with its lower limit extending low in the pelvis. Per-rectal examination revealed an intraluminal rectal mass with a smooth surface except an ulcerated area on the right side of the tip of this mass. Proctoscopy revealed normal rectal wall mucosa with an intraluminal mass having an irregular bleeding ulcer on its right side. Haemoglobin was 4.5 gm% and P.C.V. 20%. Plain X-ray of the abdomen revealed features of multiple air fluid levels in the standing film and dilated characterless ileal loops in the supine film. Barium enema revealed abrupt cut off at the level of mid-rectum. A provisional diagnosis of a chronic, partially obstructing intussusception was made.
The child was resuscitated with blood, plasma and I.V. fluids, Broad spectrum antibiotics were administered and he was then subjected to exploratory laparotomy.
At laparotomy, a caeco-colo-rectal intussusception was found which was reduced easily. There were no areas of doubtful viability though gut wall oedema was marked. The lead point (apex) of intussusception was formed by a tumour arising from the caecal wall. The draining ileocaecal lymph nodes were enlarged, firm and pinkish. The tumour like mass in the caecum was hard in consistency, irregular in outline and arising from the caecal wall itself Liver, spleen and other viscera were found normal.
Caecotomy revealed a 5 cm x 4 cm sessile, irregularly oval, firm to hard tumour arising from the caecal wall about 2.5 cm above the ileo-caecal junction with overlying mucosa ulcerated over one half of its surface. The frozen section specimen showed features of malignant tumour of lymphoid origin. Standard right hemicolectomy including all enlarged ileo-caecal lymph nodes followed by end-to-end ileo-transverse anastomosis were carried out. Abdomen was closed with a drain in the right iliac fossa.
On cut section, the tumour was found to be greyish yellow in colour with a few areas of haemorrhage in between. Microscopically, this was categorized as primary, well-differentiated, lymphocytic lymphoma of the caecum [Fig. 1]. Both resection margins and lymph nodes were tumour-free. There was no extension of the tumour through the muscle or serosa. Post-operative period was uneventful and wound healed primarily. He had been given six courses of combination chemotherapy consisting of vincristine, cyclophosphamide and prednisolone and at the last follow-up after 5 years of surgery, he has been found perfectly alright without any evidence of local recurrence, hepato-splenomegaly of involvement of other sites.
Although 90% of the cases of intussusception in adults are associated with pathological lesions of the bowel, the same is true for only 8% of cases in children. Intussusception in an older child is usually associated with primary bowel pathology and search for it may be fruitful.,  Malignant lymphoma is an occasional cause of a type of non-strangulating intussusception in older children., 
The striking correlation between intussusception in older child and the presence of malignant lymphoma has, however, not been sufficiently emphasized in previous reports., ,  The marked male predominance, age distribution of patients over 6 years and longer duration of symptoms should provide important clues to have a high index of suspicion of the malignant lymphoma as a cause of intussusception. Co-operation among a pediatrician, a radiologist and a surgeon in the management of such a child with suspected intussusception is of great importance.
If the clinical impression of intussusception is confirmed by the radiologist, its reduction must be accompanied by extensive, small intestinal reflux to rule out a primary lesion and an upper gastrointestinal series be performed after the barium is evacuated to be doubly sure. If there is any question that either the barium enema or the upper gastrointestinal series is not perfectly normal, the patient should have exploratory laparotomy.
An older child who does not have unequivocal reduction of an intussusception at barium enema, should undergo formal laparotomy and manual reduction of the intussusception followed by careful inspection and extensive search for the primary lesion responsible for it. Generally, lymphoma arises in the lymphoid follicles of the submucosa of the bowel. From this focus it proliferates into either a locally large mass or a polypoid lesion. It may invade the serosa to mesentery or beyond.
The suspicion of malignant lymphoma of the bowel should be confirmed by frozen section and a generous bowel resection as well as a large section of regional lymph node bearing mesentery should be removed. Lymph node resection, of course, is not thought to be curative, but is extremely valuable in staging the patient for future combined therapy. When a polypoidal lesion causes an intussusception at an early stage the prognosis is better than with an infiltrating tumour which may not cause significant obstruction until a late stage. Complete surgical excision together with chemotherapy using two or more cytotoxic agents produce the best results.