Colon tumor
Polyps
Tubular adenoma

Author: Charanjeet Singh, M.D. (see Authors page)

Revised: 20 December 2016, last major update August 2011

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed Search: Tubular [title] adenoma colon

Cite this page: Tubular adenoma of colon. PathologyOutlines.com website. http://pathologyoutlines.com/topic/colontumortubularadenoma.html. Accessed August 21st, 2017.
Clinical features
  • 90% of GI tubular adenomas occur in colon; also stomach and small intestine
  • 50% are single
  • Prevalence of 30% in adults at autopsy, increasing with age
  • Risk of subsequent adenomas or colorectal carcinoma is related to size; higher risk if 6 - 10 mm or larger, multiple adenomas or family history (Ann Intern Med 1998;129:273, Gut 2002;51:424)
  • May bleed due to twisting; large polyps may cause change in bowel habits or intussusception
  • Associated with hypertriglyceridemia (World J Gastroenterol 2006;12:1261)
Case reports
Gross description
  • Usually < 1 cm and pedunculated but may be sessile
  • Darker color than surrounding mucosa
  • Multiple polyps tend to cluster
Gross images

Images hosted on other servers:

Tubular adenoma

Hemorrhagic surface

Multiple cecal polyps

Microscopic (histologic) description
  • Increased number of glands and cells per unit area compared to normal mucosa
  • Cells are crowded with hyperchromatic nuclei, increased mitoses (some atypical)
  • Mucin production usually decreased
  • Changes first affect superficial portion of glands
  • Dysplasia from mild to severe (carcinoma in situ)
  • Rarely clear nuclei containing biotin, squamous metaplasia (J Surg Oncol 1984;26:130), Paneth cells, endocrine cells, malakoplakia
  • Clear cell change (Histopathology 1999;34:250) may be precursor to clear cell adenocarcinoma (Am J Surg Pathol 2010;34:1344)
  • Pseudocarcinomatous invasion: submucosal displacement and dilated adenomatous glands may mimic carcinoma (Nihon Shokakibyo Gakkai Zasshi. 2011;108:458, Gut Liver 2009;3:130)
Microscopic (histologic) images

Images hosted on other servers:

Tubular adenoma

Compared to normal mucosa

With osseous metaplasia

Pseudocarcinomatous invasion

Positive stains
  • bcl2 (almost all cases), increased CEA (in atypical areas)
Negative stains
  • p53 (usually)
Molecular / cytogenetics description
  • 1 / 3 are aneuploid
  • Depending on the villous component, two types of tubular adenomas can be identified (Am J Surg Pathol 2011;35:212):
    • TA1: less than 1% villous component, lower rate of p53 overexpression, Kras mutation and MGMT loss
    • TA2: 1 - 20% villous component, higher rate of p53 and Kras mutation and MGMT loss