Primary gallbladder melanoma - a rare entity or a diagnostic pitfall?

Area of Science:

• Gastroenterology
• Oncology
• Dermatology

Background:

• Primary gastrointestinal (GI) melanoma is a rare and controversial diagnosis.
• Most GI melanomas are considered metastatic from cutaneous melanoma, but primary origin is debated.
• Diagnosis is complicated by occult, amelanotic, or regressed primary cutaneous melanomas.

Purpose of the Study:

• To review literature on GI and gallbladder melanoma.
• To differentiate primary versus metastatic lesions.
• To analyze recent cases of GI and gallbladder melanoma.

Main Methods:

• Literature review of GI and gallbladder melanoma.
• Analysis of three departmental cases diagnosed within five years.
• Clinicopathological evaluation.

Main Results:

• Three cases identified: one gallbladder melanoma, two small bowel melanomas.
• Cases presented diverse clinical scenarios including GI bleeding and amelanotic melanoma.
• Findings highlight diagnostic challenges in differentiating primary GI melanoma.

Conclusions:

• Cautious interpretation is crucial when diagnosing primary GI melanoma.
• Metastatic disease from occult or regressed cutaneous melanoma must be excluded.
• Multidisciplinary clinicopathological evaluation is essential.