Metastatic melanoma of the gallbladder

Abstract

Metastatic involvement of the gallbladder in melanoma is rare, but constitutes the most common metastatic lesion involving this organ. Two cases of metastatic melanoma to the gallbladder with radiographic evidence of gallbladder abnormality prior to surgery are presented. These cases are compared to the nine previously reported cases of metastatic melanoma to the gallbladder with abnormal cholecystograms. All eleven cases presented with signs and symptoms compatible with cholecystitis. Nine of the eleven patients had a previous melanoma primary and most had other extrabiliary metastases. Associated cholelithiasis appeared to be only incidental. In addition, nine reported cases of "primary" biliary melanoma were reviewed. Clinical and pathologic presentations in the latter cases were similar to the former cases with metastases. Seventy-eight percent had extrabiliary sites of metastasis at some time in the course of their disease, tending to refute the impression of "primary" biliary melanoma. Melanoma in the gallbladder is much more likely to have metastasized from a regressed skin primary than to have arisen de novo. The two reported cases and the 18 cases from the literature indicate that the physician must consider gallbladder metastasis in melanoma patients presenting with symptoms compatible with cholecystitis.

Primary gallbladder melanoma in dysplastic nevus syndrome: Report of case and literature review

“…All of these criteria for distinguishing primary from secondary malignant melanoma in the gallbladder are weak, especially if we look at them separately. In fact, metastatic melanoma can have polypoid pattern (31), or may be in the form of a single tumor mass (22,32), or can show intraepithelial spread and junctional activity, or can be a single metastatic position (33,35,36). There are recommendations about the obvious presence of certain characteristics (23) for making the diagnosis of this primary entity.…”

“…After the initial opinion that those metastases are rare in the gastrointestinal tract (GIT), there is growing evidence that they account for 15% in the gallbladder (29). Although metastases in the gallbladder are a rare event, malignant melanoma represents 50-60% of them (30)(31)(32). The most conflicting area is the histogenesis of this primary entity or its possibility.…”

Primary malignant melanoma of the gallbladder in dysplastic naevus syndrome

“…Nevertheless, the acquisition of further evidence for or against the occurrence of such a pathology would be highly opportune. The criteria proposed by the specific literature for distinguishing a GPMM from a secondary gallbladder melanomatous involvement are the following: (1) the exclusion of a previous primitive melanoma, (2) the absence of synchronous involvement of sites other than the considered one, (3) the unicity of the lesion, (4) its polypoid or papillary shape and (5) the presence of a junctional melanocitary component [4,7,12,13,16,17,18,23]. These criteria are, however, very weak, especially if singly taken.…”

“…As a matter of fact, widely accepted objective criteria of primitivity are lacking. The proposed requirements for primitivity assessment [13,18] have been often criticised [14,17], so that many of the reported cases of primary malignant melanoma of the gallbladder have been questioned [13,20], and doubts about the possible occurrence of such a pathology have been raised [14,20]. Having established that melanoma is the neoplastic type most frequently responsible for metastatic involvement of gallbladder, accounting for over 50% of such events [7,20], and that about 15% of disseminated melanoma involve gallbladder [20], justifies this scepticism.…”

Differential features of some unusual biliary tumors

“…Obstructive jaundice may also be caused by many different neoplasms metastatic to the biliary system: lung [34], breast [37], colon [38,39], testicle [40], prostate [41], melanoma [42], pancreas [43,44] and gallbladder [39]. The age range of the patients in these reports corresponded to the peak incidence of the various primary tumors.…”