Rectal Carcinoids

Current Clinical Trials

In general, rectal carcinoids smaller than 1 cm can be safely removed by endoscopic excision.[1] Excised specimens should be examined histologically to exclude muscularis invasion.[2-5]

Tumors measuring 1 cm to 2 cm should be investigated by transanal endosonography or magnetic resonance imaging. Absence of muscularis invasion or regional metastases may justify local excision.[1] The outcome from treating a lesion between 1 cm and 2 cm is unclear. The metastatic risk is between 10% and 15%.[6] Some studies demonstrate no benefit with aggressive management whereas other studies have reported successful treatment with local or radical surgery.[2,7,8] Although it may be possible to recognize tumors with particular atypia and high mitotic index before embarking on radical surgery, the presence of muscularis invasion or regional metastases generally supports aggressive excision. Generally, the procedure is an anterior rectal resection with total mesorectal excision and regional lymphadenectomy. In patients with distant metastases, prognosis is generally poor with an overall 5-year survival rate of approximately 30%.[1]

A similar approach to that used for tumors measuring 1 cm to 2 cm is used in patients with tumors larger than 2 cm but with no metastasis. However, rectal carcinoids of 1 cm to 2 cm have a substantially higher metastatic risk, between 60% and 80%.[2,6,9,10] Invasion of the muscularis propria is common in these tumors and indicates a high metastatic potential.[11] Local resection is unlikely to benefit patient survival with metastatic disease, but it may provide local symptomatic relief.[12] Locoregional resection may control local symptoms and pelvic disease without improving survival.[13,14] Although studies are limited, and the numbers of tumors studied are consistently small, aggressive surgery has not been shown to improve the survival outcome in this group of patients.[11]

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor ¹ and regional gastrointestinal carcinoid tumor ². The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.

General information about clinical trials is also available from the NCI Web site ³.

References

1. Akerström G, Hellman P: Surgery on neuroendocrine tumours. Best Pract Res Clin Endocrinol Metab 21 (1): 87-109, 2007.  [PUBMED Abstract]
   
   
2. Koura AN, Giacco GG, Curley SA, et al.: Carcinoid tumors of the rectum: effect of size, histopathology, and surgical treatment on metastasis free survival. Cancer 79 (7): 1294-8, 1997.  [PUBMED Abstract]
   
   
3. Suzuki H, Ikeda K: Endoscopic mucosal resection and full thickness resection with complete defect closure for early gastrointestinal malignancies. Endoscopy 33 (5): 437-9, 2001.  [PUBMED Abstract]
   
   
4. Vogelsang H, Siewert JR: Endocrine tumours of the hindgut. Best Pract Res Clin Gastroenterol 19 (5): 739-51, 2005.  [PUBMED Abstract]
   
   
5. Akerström G, Hellman P, Hessman O: Gastrointestinal carcinoids. In: Lennard TWJ, ed.: Endocrine Surgery. 4th ed. Philadelphia, Pa: WB Saunders Ltd, 2009, pp 147-76. 
   
   
6. Mani S, Modlin IM, Ballantyne G, et al.: Carcinoids of the rectum. J Am Coll Surg 179 (2): 231-48, 1994.  [PUBMED Abstract]
   
   
7. Jetmore AB, Ray JE, Gathright JB Jr, et al.: Rectal carcinoids: the most frequent carcinoid tumor. Dis Colon Rectum 35 (8): 717-25, 1992.  [PUBMED Abstract]
   
   
8. Higaki S, Nishiaki M, Mitani N, et al.: Effectiveness of local endoscopic resection of rectal carcinoid tumors. Endoscopy 29 (3): 171-5, 1997.  [PUBMED Abstract]
   
   
9. Sauven P, Ridge JA, Quan SH, et al.: Anorectal carcinoid tumors. Is aggressive surgery warranted? Ann Surg 211 (1): 67-71, 1990.  [PUBMED Abstract]
   
   
10. Modlin IM, Lye KD, Kidd M: A 5-decade analysis of 13,715 carcinoid tumors. Cancer 97 (4): 934-59, 2003.  [PUBMED Abstract]
    
    
11. Plöckinger U, Rindi G, Arnold R, et al.: Guidelines for the diagnosis and treatment of neuroendocrine gastrointestinal tumours. A consensus statement on behalf of the European Neuroendocrine Tumour Society (ENETS). Neuroendocrinology 80 (6): 394-424, 2004.  [PUBMED Abstract]
    
    
12. Schindl M, Niederle B, Häfner M, et al.: Stage-dependent therapy of rectal carcinoid tumors. World J Surg 22 (6): 628-33; discussion 634, 1998.  [PUBMED Abstract]
    
    
13. Teleky B, Herbst F, Längle F, et al.: The prognosis of rectal carcinoid tumours. Int J Colorectal Dis 7 (1): 11-4, 1992.  [PUBMED Abstract]
    
    
14. Berkelhammer C, Jasper I, Kirvaitis E, et al.: "Band-snare" resection of small rectal carcinoid tumors. Gastrointest Endosc 50 (4): 582-5, 1999.  [PUBMED Abstract]