Gallbladder Polyps
September  2015

​A 67 year-old male is applying for $1 million of life insurance. Records reveal he was recently evaluated for epigastric pain.

After an abdominal ultrasound and blood work evaluation, he was diagnosed with GERD. He responded well to typical reflux management and became asymptomatic. The ultrasound of the abdomen revealed a solitary 1.3 cm gallbladder polyp. There were no other abnormalities seen in the gallbladder, including absence of stones. It was felt to be an incidental finding. There was no family history of cancer. He was referred to a gastroenterologist for further evaluation of the polyp, but that consultation was not available at the time of application.

What are the mortality considerations of an incidentally discovered gallbladder polyp?
Lesions projecting into the gallbladder cavity from the gallbladder wall are referred to as gallbladder polyps. Gallbladder polyps can be malignant or benign, although most are benign. Benign polyps can be pseudotumors such as cholesterol polyps, inflammatory polyps, or tumors such as adenomas, fibromas, lipomas, or leiomyomas. The most common benign polyp is the cholesterol polyp (up to 70%). The most common malignant polyps of the gallbladder are adenocarcinomas (3%-8% of all polyps).

Figure 1 - Gallbladder Polyps
gallbladder lesion polyp
A lesion projecting into the gallbladder cavity from the gallbladder wall (arrow) is referred to as a gallbladder polyp.

Incidence & Prognosis
It is not uncommon to see gallbladder polyps mentioned in the imaging results of proposed insured applicant’s records. There are several contributing factors. First, abdominal pain is a common presenting complaint to physician’s offices. Second, ultrasonography imaging technology (US) is a commonly used medical test that is relatively inexpensive, readily available and felt to be safe. Third, the incidence of gallbladder polyps in the general population, according to many citations, is between 3%-7%. Finally, the US is considered very sensitive in detecting gallbladder polyps.

The underwriter’s dilemma is determining whether there is a significant risk for malignancy when a gallbladder polyp is mentioned in the records. This distinction is especially important because of the typically poor prognosis of gallbladder cancer. While a rare malignancy (about 4,000 new cases per year in the US) gallbladder cancer unfortunately is not usually discovered until it is in an advanced state (approximately 20% found in early stage). The overall prognosis for gallbladder cancer is poor, with a five-year survival rate of approximately 10%.

Risk of Malignancy

Moreover, completely ruling out an early cancer when a polyp is found is difficult. However, some characteristics increase the likelihood of cancer:

  • The polyp is greater than 1 cm in size.
  • The individual is 50 years old or older.
  • The presence of a solitary polyp, a symptomatic polyp, or concurrent gallstones.

The presence of any of the conditions above increases the chance for malignancy. Additionally, thickness of the gallbladder wall in association with a gallbladder polyp has been found to be associated with malignancy (Figure 3).

Figure 3 - Gallbladder Polyps: Characteristics of Concern

​Size

​> 1cm (43% - 77% chance of malignancy
​> 2 cm (almost always malignant)

​Individual's Age​> 50 years old
​# of Polyps​Solitary are of more concern
​Symptoms​Symptoms are of concern
​Gallstone Presence​Concurrent gallstones are of concern
​Gallbladder Appearance​Increased gallbladder wall thickness is concerning
​Comorbid Conditions​More concern when associated with sclerosing cholangitis


Diagnosis & Treatment
Serial imaging is commonly recommended when small polyps with no risk factors are discovered. If there is a strong suspicion of possible malignancy, surgical removal is commonly advocated. This is especially true since surgery is the only potentially curative therapy for gallbladder cancer and early-stage treatment is imperative to increase survival.

Returning to the Case
In this particular case the finding of a gallbladder polyp should be of significance to the underwriting team. While we acknowledge that most polyps are benign there are several issues in this case which raise concern about the possibility of current or future malignancy. The polyp size (1.3 cm) and the age of the individual (67 years old) increase the chance for malignancy. Finally, the investigation and recommendation from the clinical team is incomplete, and it would be prudent to await full evaluation of this abnormal US finding prior to an offer.

References
Baltayiannis, N. et al. “Gallbladder polyps: Diagnosis and treatment.” Hellenic Journal of Surgery. 2010 Aug.
Corwin, Michael T. et al. “Incidentally detected gallbladder polyps: Is follow-up necessary: Long-term clinical and US analysis of 346 patients.” Radiology. 2011 Jan; 258. P 278-82
Koga, A. “Diagnosis and operative indications for polypoid lesions of the gallbladder.” Arch. Surg. 1988; 123; 26.
Lee, KF, et al. “Polypoid lesions of the gallbladder.” Am. J Surg. 2004; 188(2): 186-90.
Saleh, Huain, et al. “Polypoid lesions of the gallbladder: Diagnostic and management challenges.” J. Gastrointestin Liver Dis. 2008 Sep; 17(3) 251-3.
http://www.cancer.org/cancer/gallbladdercancer/detailedguide/gallbladder-key-statistics. Accessed 2/19/15.
Zakko, Wisam, et al. “Gallbladder polyps and cholesterolosis.” UpToDate. Accessed 6/15/15.