Problems in determining the prognosis of asymptomatic gallstones

Abstract

Decisions as to whether to perform prophylactic cholecystectomy on patients with asymptomatic gallstones require better information on the rate of development of complications than presently exists. The published data are scanty, are probably applicable only to whites, frequently do not clearly define the symptom status of patients at entry to the study, and contain little information that identifies subgroups with differing prognoses. Efforts to overcome these deficiencies and problems encountered in the design of a new follow-up study are described. In the absence of cholecystograms performed routinely on asymptomatic persons it is difficult to assemble a cohort of patients with silent gallstones suitable for a follow-up study. Other methods of identifying such patients may require that follow-up for the study start later than the time when stones were first demonstrated. Characteristics that should be ascertained at entry include demographic and important clinical features, the number and type of stones and the patient’s symptoms. Follow-up should include the various complications of cholelithiasis, and whether cholecystectomy was later performed. All dates on which these significant events occur should be noted.

The medical profession continues to debate what to do for the patient with asymptomatic gallstones. One point of view, often held by surgeons, is that cholecystectomy should be performed immediately. The rationale for this approach may be stated as follows: cholecystectomy is quite safe when the patient is asymptomatic and it will prevent later complications resulting from gallstones. If one waits for symptoms to develop, the patient will be sick and older and much less able to tolerate surgery. Further, if the stones are not removed the patient is at risk of developing cancer of the gallbladder, which is usually incurable by the time it is discovered.

The other policy, often advocated by internists, is that cholecystectomy should not be performed unless and until the patient develops clear-cut symptoms or complications of cholelithiasis. The rationale for this approach is as follows: although prophylactic cholecystectomy is relatively safe, some otherwise healthy patients will die due to the surgery or anaesthesia. In terms of years of life lost, this tragic and unnecessary early mortality more than makes up for the greater mortality, surgical and otherwise, if complications occur later; and in many persons with gallstones these complications never occur. Also, routine identification and removal of all gallbladders with stones would be a very costly policy and would overload our surgical resources. Further, the risk of gallbladder cancer in persons with gallstones is very low and there is recent evidence¹ that cholecystectomy increases the risk of colon cancer, a much more common malignancy.

Resolution of this dilemma rests to a large extent on determining the rate at which complications develop in persons with asymptomatic gallstones. There is surprisingly little information about this, and examination of the few published studies points up another critical question — what do we mean by ‘asymptomatic gallstones’ and how often are patients who are discovered to have gallstones truly asymptomatic?