|Year : 2013 | Volume
| Issue : 4 | Page : 746-747
Combined adenocarcinoma-carcinoid tumor of transverse colon
Prosanta Kumar Bhattacharjee, Shyamal Halder
Department of Surgery, I.P.G.M.E & R/S.S.K.M Hospital, Kolkata, West Bengal, India
|Date of Web Publication||11-Feb-2014|
Prosanta Kumar Bhattacharjee
Bhattacharjee, Flat No 5, 4th Floor, Suryatoran Apartment, 114/A, Barasat Road, Kolkata - 700 110
Source of Support: None, Conflict of Interest: None
A 65-year-old male presented with painless hematochezia associated with episodic cramps in upper abdomen, watery diarrhea, and a slowly growing mass in upper abdomen. Examination revealed a firm 6 x 5 cm, intra-abdominal, epigastric mass. Colonoscopy up to 90 cm showed a stenosing, ulcero-proliferative lesion in the transverse colon. No synchronous lesion was detected. Biopsy revealed mucin secreting adenocarcinoma. Exploration showed the growth involving the transverse colon proximal to the splenic flexure with a part of ileum, approximately three feet proximal to ileo-caecal junction, adherent to it. No significant mesenteric lymph node enlargement was evident. The patient underwent resection of the growth along with the segment of adherent ileum. Continuity was re-established by a colo-colic and ileo-ileal anastomosis respectively. Patient received adjuvant chemotherapy. Post-operative histopathology demonstrated a composite histological pattern with an admixture of carcinoid tumor and adenocarcinoma, invasion of ileal serosa and adenocarcinomatous deposits in mesocolic lymph nodes, the tumor staging being (T4, N0, M0/Stage II) for carcinoid and (T4, N1, M0/Stage III) for adenocarcinoma. Patient was followed-up for a year and was doing well without any evidence of recurrence.
Keywords: Adenocarcinoma, carcinoid, composite tumor, transverse colon
|How to cite this article:|
Bhattacharjee PK, Halder S. Combined adenocarcinoma-carcinoid tumor of transverse colon. J Can Res Ther 2013;9:746-7
| > Introduction|| |
Composite carcinoid-adenocarcinomas (adeno carcinoids) are uncommon tumors. These tumors have histological features of both carcinoid and adenocarcinoma which are intermixed but with a definite transition between the two different components. 
Such composite tumors have been reported in various locations along the gastrointestinal tract, the appendix being the most common.  Here we report a rare case of composite carcinoid-adenocarcinoma of the transverse colon in a 65-year-old patient.
| > Case Report|| |
A 65-year-old male presented with history of painless passage of bright red blood per anum for 5 months, episodic cramps over mid upper abdomen for 3 months, slowly growing mid upper abdominal mass and intermittent episodes of watery diarrhea for 2 months. He had no family history of cancer or colonic polyps.
Physical examination revealed moderate degree of skin pallor, bilateral pedal edema and an ovoid, firm, 6 × 5 cm, mobile, slightly tender, intra-abdominal lump in the epigastric region.
There was no cervical lymphadenopathy or other organomegaly and pelvic examination was normal.
Routine and laboratory studies were unremarkable except for hemoglobin of 6.4 g% and serum albumin of 2.1 g%. Serum carcinoembryonic antigen level was 3 ng/ml.
Colonoscopy showed a stenosing, ulcero-proliferative growth, approximately 90 cm from the anal verge, through which the scope could be negotiated with difficulty. No synchronous lesion was detected. The biopsy revealed mucin secreting adenocarcinoma. The patient underwent a staging contrast enhanced computed tomography scan of the abdomen and pelvis which demonstrated poorly enhancing circumferential thickening the transverse colon proximal to the splenic flexure. The fat planes were lost on its antero-inferior aspect near a narrowed segment of small intestine. There was no evidence of regional lymph node enlargement or distant metastases.
Exploration after proper evaluation showed the growth involving the transverse colon proximal to the splenic flexure with a loop of ileum, approximately three feet proximal to the ileo-cecal junction, adherent to it. No significant mesenteric lymph node enlargement or other evidence of metastasis was evident.
The patient underwent a transverse colectomy along with segmental resection of the adherent ileal loop followed by colo-colic and ileo-ileal anastomosis respectively. The post-operative histopathology demonstrated a composite histological pattern with distinct areas of carcinoid tumor arranged in nests intermingled with well differentiated adenocarcinoma [Figure 1]. The tumor had invaded through the muscle layer onto the serosa of the adherent ileum. The resection margins were free of tumor. Two mesocolic lymph nodes out of 14 showed metastatic adenocarcinomatous deposit but all lymph nodes in the resected portion of the ileal mesentry showed reactive hyperplasia. Thus the pathological staging of the adenocarcinomatous component was (T4, N1, M0/Stage III) while that of the carcinoid tumor was (T4, N0, M0/Stage II).
|Figure 1: Section showing both mucin secreting adenocarcinoma (upper part) and carcinoid components (lower part); (H and E, ×4)|
Click here to view
Immunohistochemical staining with Chromogranin-A confirmed the presence of carcinoid component.
Post-operative recovery was uneventful and the patient was discharged on the 10 th post-operative day. He received adjuvant chemotherapy Folinic acid, 5 FU and oxaliplatin (Folfox, four cycles).
He was followed-up for about a year after completion of his adjuvant chemotherapy and was doing well without any evidence of local or distant recurrence.
| > Discussion|| |
Though Hamperl in 1927 was the first to report neuroendocrine cells in adenocarcinomas of the gastrointestinal tract, it was in 1988 that Moyna et al. first described the composite adeno-carcinoid tumor of the large intestine. , 5-10% of colorectal cancers may have a neuroendocrine component in them. 
When the two tumor elements are in proximity but with a distinct boundary between them, they are termed as collision tumor and when they are intermixed they are termed composite tumor.
Sometimes individual tumor cells may show positive staining for both mucin and argentaffin cells. This cannot be explained as a composite of two independent neoplasms which have grown together. A more plausible explanation is neoplastic differentiation in two different directions from a single multipotent precursor cell line. 
It is pertinent in this regard to mention that the theory of neural crest origin of the carcinoid tumor is debatable if the single cell line theory as mentioned above is true.
There are reports of composite adenocarcinoma and carcinoid tumor of the colon occurring in patients with longstanding ulcerative colitis.  Few reports, as ours, are also available describing denovo origin of such tumors, suggesting factors other than inflammatory bowel disease may be responsible in the genesis of composite adenocarcinoid tumors of the large bowel. 
Composite tumor of the gastrointestinal tract in itself is unusual. It has been described in appendix, caecum, stomach, small intestine, esophagus, rectum and anal canal.  Literature search revealed only few reports of its occurrence in transverse colon as in this reported case but all had lesion limited to the colonic wall without involvement of regional nodes. 
These tumors behave more like adenocarcinomas than carcinoids but have a worse prognosis than ordinary adenocarcinoma. 
The FOLFOX regimen is recommended for patients with node positive colorectal adenocarcinoma and is associated with longer progression-free survival.
| > References|| |
|1.||Lewin K. Carcinoid tumors and the mixed (composite) glandular-endocrine cell carcinomas. Am J Surg Pathol 1987;11:71-86. |
|2.||Jain M, Das KK. Concurrent occurrence of terminal ileum carcinoid tumor and cecal adenocarcinoma: A collision tumor or composite tumor? Indian J Pathol Microbiol 2009;52:285-6. |
|3.||Capella C, La Rosa S, Uccella S, Billo P, Cornaggia M. Mixed endocrine-exocrine tumors of the gastrointestinal tract. Semin Diagn Pathol 2000;17:91-103. |
|4.||Moyana TN, Qizilbash AH, Murphy F. Composite glandular-carcinoid tumors of the colon and rectum. Report of two cases. Am J Surg Pathol 1988;12:607-11. |
|5.||Lyss AP, Thompson JJ, Glick JH. Adenocarcinoid tumor of the colon arising in preexisting ulcerative colitis. Cancer 1981;48:833-9. |
|6.||Anagnostopoulos GK, Arvanitidis D, Sakorafas G, Pavlakis G, Kolilekas L, Arkoumani E, et al. Combined carcinoid-adenocarcinoma tumour of the anal canal. Scand J Gastroenterol 2004;39:198-200. |
|7.||Ranganath R, Ramakrishnan AS, Ayyappan A, Vikas M. Adenocarcinoid tumors of the gastrointestinal tract: Case report and review of the literature. Internet J Surg 2007;10(1) |