Villous Adenoma Clinical Presentation

Updated: Oct 24, 2016
  • Author: Alnoor Ramji, MD, FRCPC; Chief Editor: Burt Cagir, MD, FACS  more...
  • Print
Presentation

History

Note that the vast majority of patients are asymptomatic and have unremarkable laboratory findings. Approximately two thirds of colorectal polyps are asymptomatic. Any nonspecific intestinal symptoms are more likely to be coincidental. For example, bright red rectal bleeding in a patient in whom a small colonic polyp is eventually found is still most likely to be hemorrhoidal in origin. Polyps greater than 1 cm are more likely to produce symptoms, usually rectal bleeding, abdominal pain, and a change in bowel habits. Note the following:

  • The most common presenting symptom is occult/overt bleeding (hematochezia) with an anemia, which may be microcytic. Polyps may bleed only intermittently into the stromal component, thus accounting for inconsistent findings.
  • Nonspecific symptoms include diarrhea, constipation, and flatulence. A change in stool caliber (ie, the classic pencil-thin stools), although still described in older textbooks, is an entirely nonspecific and unreliable symptom. Pencil-thin stools, if truly present, would be secondary to large distal adenomas or frank carcinomas.
  • When intense cramping occurs, torsion or episodic intussusception due to larger adenomas may be considered.
  • Villous adenomas rarely cause a secretory diarrhea syndrome. The tumor usually is located at the rectosigmoid or rectum and often is 3-4 cm in diameter. Stool volumes of 350-3000 mL are reported and may cause hypovolemia and metabolic imbalances.
  • Patients may have a family history of polyps and colon cancer. Using data obtained from the prospective Health Professionals Follow-Up Study, in which men underwent endoscopy between 1986 and 2004, Wark et al examined whether a family history of colorectal cancer is associated with advanced adenoma stage, defined as 1 cm or larger and a histology with villous component or carcinoma in situ, or adenoma multiplicity. [3] Twenty-one percent of 3881 patients with adenoma and 13.9% of 24,959 adenoma-free men had a first-degree relative with colorectal cancer. The investigators found a number of positive associations with a family history of colorectal cancer including advanced and advanced adenomas, with the possibility of potential differences due to adenoma location, as well as the number of adenomas and presence of multiple distally located adenomas. [3] Wark et al suggested that at the population level, their findings may demonstrate a greater significance of heritable factors in earlier stages of adenoma formation than at stages of adenoma advancement for at least distally located adenomas. [3]
  • Patients with villous adenomas of the ampulla usually present with intermittent or progressive jaundice, abdominal pain, intestinal hemorrhage, or pancreatitis.
Next:

Physical

Patients often have no findings on bedside physical examination.

Occasionally, a palpable mass is present upon digital rectal examination.

Jaundice may be present with villous adenoma of the ampulla.

Previous
Next:

Causes

Genetic factors

From the NPS data, relatives of patients with polyps have an increased risk of carcinoma. This includes siblings of patients with adenomas detected prior to age 60 years or siblings of patients with adenomas detected at any age if either parent has colorectal cancer. Offer these patients screening colonoscopy every 5 years after age 40 years.

Lifestyle and diet

Foods and vitamins that have a protective effect against adenomas include dietary fiber, plant foods, carbohydrates, and folate supplementation. Excess fat and alcohol are positively correlated with adenoma risk. A strong association exists between cigarette smoking and adenoma size. Supplemental vitamins C and E are not considered protective.

Acromegaly

Patients with acromegaly have an increased risk of adenomas and colon cancer. Prevalence rates of 14-35% for adenomas are reported. The mechanism for increased risk is not known.

Streptococcus bovis bacteremia

This causes an increased risk of adenomas, carcinomas, and, possibly, familial adenomatous polyposis (FAP). These patients should undergo colonoscopy. Patients with endocarditis from Streptococcus agalactiae infection are reported to have an increased risk of rectal villous adenoma and should be evaluated.

Atherosclerosis and cholesterol

Autopsy studies report a positive correlation between the degree of atherosclerosis and adenoma size, dysplasia, and multiplicity.

Uterosigmoidostomy sites

Patients who undergo urinary diversion procedures are at increased risk of developing polyps or carcinomas at uterosigmoidostomy sites as many as 38 years later. Prevalence rates of 29% are reported.

Inflammatory bowel disease (IBD)

In patients with IBD who develop carcinomas, 50% of the lesions are found to be juxtaposing serrated or villous adenomas. These possibly are the lesions from which the carcinomas originate. However, a dysplasia-associated lesion or mass is reported to be the premalignant lesion of adenocarcinoma in ulcerative colitis, in which the adenoma-carcinoma sequence is not preserved.

Other conditions

Historically, some conditions have been thought to be correlated with increased incidence of polyps. These conditions include acrochordons (skin tags), breast cancer, and cholecystectomy, for which no evidence exists of an increased risk for adenoma.

Previous