Colon
Mesenchymal tumors
Lipoma
Author: Raul S. Gonzalez, M.D.
Last author update: 29 January 2021
Last staff update: 6 April 2023
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed Search: Lipoma colon
Table of Contents
Definition / general | Essential features | Epidemiology | Sites | Clinical features | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Sample pathology report | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Gonzalez RS. Lipoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/colontumorlipoma.html. Accessed July 15th, 2024.
Definition / general
- Benign colonic neoplasm composed of mature adipose tissue
Essential features
- Most common submucosal mesenchymal lesion of colon
- Typically small and benign but can cause symptoms if large
Epidemiology
- Incidence may be as high as 4.4% but is more likely less than 1% (Gastroenterol Hepatol (N Y) 2011;7:490)
Sites
- Usually submucosal in right colon
Clinical features
- More common in elderly patients
- Larger lesions can cause symptoms, such as abdominal pain and intussusception (Am Surg 2006;72:83)
- Typically solitary but rare patients may have multiple or diffuse lesions (Histopathology 2001;38:81)
- Patients may have concurrent malignancy (J Surg Oncol 1991;47:170)
Case reports
- 83 year old woman with ascending colon lipoma (World J Gastroenterol 2005;11:3167)
Treatment
- Removal by colonoscopy or surgery (Eur J Surg 1991;157:51)
Gross description
- Soft, yellow cut surface
- Size can vary; large lesions may have overlying ulceration
Gross images
Images hosted on other servers:
Large pedunculated submucosal tumor
Cut section of tumor
Microscopic (histologic) description
- Benign, well circumscribed (but not encapsulated) adipose tissue, usually in the submucosa
- Some cases may show prominent fibrosis or vasculature (Virchows Arch 2019;474:309)
- Overlying mucosa usually normal but may show an adenoma or a serrated polyp (World J Clin Cases 2013;1:124)
- May have overlying mucosal ulceration, atypical stromal cells and florid vascular proliferation due to repeated intussusception (Pathol Int 2005;55:160)
- Intramucosal lipomas may occur sporadically or in Cowden syndrome (Mod Pathol 2018;31:643)
Microscopic (histologic) images
Contributed by Raul S. Gonzalez, M.D.
Intramucosal lipoma
Images hosted on other servers:
Lipoma with overlying sessile serrated adenoma
Sample pathology report
- Ascending colon, polypectomy:
- Colonic mucosa with focus of benign submucosal fat, compatible with lipoma
- Descending colon, polypectomy:
- Intramucosal lipoma (see comment)
- Comment: Intramucosal lipomas have been associated with Cowden syndrome in some patients. Additional clinical evaluation may be warranted.
Differential diagnosis
- Lipomatous hypertrophy of ileocecal valve:
- Also benign; not well circumscribed
- Pseudolipomatosis:
- Artifact caused by air insufflation or disinfectant (Gastrointest Endosc 1989;35:93)
- Should not form a mass
- Numerous small rounded empty spaces without nuclei; S100 negative (Ulus Cerrahi Derg 2015;32:90)
Board review style question #1
Benign fatty lesions of the colon usually arise in what layer of the wall?
- Lamina propria
- Muscularis mucosae
- Muscularis propria
- Submucosa
- Subserosa
Board review style answer #1
