Diagnosis of metastatic melanoma in a patient treated with infliximab

We present the case of a 73-year-old man diagnosed with ileocolic Crohn's disease under treatment with infliximab who was admitted due to deterioration of general condition and abdominal pain. An abdominal CT scan was performed in which several lymphadenopathies were observed on the left flank that formed a polylobed mass of 3.4 cm. Gastroscopy was performed, requested for anemia, observing a protruding lesion of about 5 mm of blackish hue in the duodenal bulb that was biopsied, resulting in malignant melanoma. A capsule endoscopy study was also performed, observing numerous blackish patches of up to 3 mm in the proximal jejunum, suggestive of melanoma metastasis. After examining the patient, a nodular lesion of about 7 mm in diameter compatible with melanoma was identified in the posterior cervical region. Subsequently, an ultrasound-guided core needle biopsy of the previously described left flank mass was performed, resulting in melanoma infiltration. Finally, a whole-body PET-CT scan with fluordeoxyglucose F-18 was performed, finding a hypermetabolic abdominal mass suggestive of malignancy with locoregional adenopathies associated with a pulmonary nodule and multiple muscle implants and subcutaneous cellular tissue. Given these findings, the patient is diagnosed with metastatic melanoma. The digestive tract is one of the most common places where melanoma metastases occur. Diagnosis is usually made using radiological or endoscopic techniques. Endoscopically it can present as a nodule, a solitary ulcer or a pigmented or non-pigmented mass [1] [2] [3].

Publication History

Article published online:
27 March 2025

• References

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