Hydatid cyst of the pancreas: Report of an undiagnosed case of pancreatic hydatid cyst and brief literature review

Aim: To overview the literature on pancreatic hydatid cyst (PHC) disease, a disease frequently misdiagnosed during preoperative radiologic investigation.

Methods: PubMed, Medline, Google Scholar, and Google databases were searched to identify articles related to PHC using the following keywords: hydatid cyst, hydatid disease, unusual location of hydatid cyst, hydatid cyst and pancreas, pancreatic hydatid cyst, and pancreatic echinococcosis. The search included letters to the editor, case reports, review articles, original articles, meeting presentations and abstracts that had been published between January 2010 and April 2014 without any restrictions on language, journal, or country. All articles identified and retrieved which contained adequate information on the study population (including patient age and sex) and disease and treatment related data (such as cyst size, cyst location, and clinical management) were included in the study; articles with insufficient demographic and clinical data were excluded. In addition, we evaluated a case of a 48-year-old female patient with PHC who was treated in our clinic.

Results: A total of 58 patients, including our one new case, (age range: 4 to 70 years, mean ± SD: 31.4 ± 15.9 years) were included in the analysis. Twenty-nine of the patients were female, and 29 were male. The information about cyst location was available from studies involving 54 patients and indicated the following distribution of locations: pancreatic head (n = 21), pancreatic tail (n = 18), pancreatic body and tail (n = 8), pancreatic body (n = 5), pancreatic head and body (n = 1), and pancreatic neck (n = 1). Extra-pancreatic locations of hydatid cysts were reported in the studies involving 44 of the patients. Among these, no other focus than pancreas was detected in 32 of the patients (isolated cases) while 12 of the patients had hydatid cysts in extra-pancreatic sites (liver: n = 6, liver + spleen + peritoneum: n = 2, kidney: n = 1, liver + kidney: n = 1, kidney + peritoneum: n = 1 and liver + lung: n = 1). Serological information was available in the studies involving 40 patients, and 21 of those patients were serologically positive and 15 were serologically negative; the remaining 4 patients underwent no serological testing. Information about pancreatic cyst size was available in the studies involving 42 patients; the smallest cyst diameter reported was 26 mm and the largest cyst diameter reported was 180 mm (mean ± SD: 71.3 ± 36.1 mm). Complications were available in the studies of 16 patients and showed the following distribution: cystobiliary fistula (n = 4), cysto-pancreatic fistula (n = 4), pancreatitis (n = 6), and portal hypertension (n = 2). Postoperative follow-up data were available in the studies involving 48 patients and postoperative recurrence data in the studies of 51 patients; no cases of recurrence occurred in any patient for an average follow-up duration of 22.5 ± 23.1 (range: 2-120) mo. Only two cases were reported as having died on fourth (our new case) and fifteenth days respectively.

Conclusion: PHC is a parasitic infestation that is rare but can cause serious pancreato-biliary complications. Its preoperative diagnosis is challenging, as its radiologic findings are often mistaken for other cystic lesions of the pancreas.