Melanoma and Sarcoidosis in Patients Receiving or Not Antineoplastic Therapy

Sarcoidosis and sarcoid-like reactions have been associated with many solid tumors including malignant melanoma. There are reports of melanoma patients who develop sarcoidosis without having received any antineoplastic treatment, but there are also melanoma patients who have received immunotherapy or targeted therapy and, therefore, develop drug-associated sarcoidosis. Herein, we describe 2 cases of thoracic sarcoidosis which occurred in asymptomatic patients with known malignant melanoma. The first patient had metastatic disease, and she was under melanoma treatment with BRAF/MEK inhibitors at the time of sarcoidosis diagnosis. The second case involves a patient with early stage melanoma who had received no antineoplastic treatment. In both cases, the thoracic lesions were suspicious for metastatic involvement, and it was the biopsy which gave the diagnosis of granulomatous disease. Sarcoidosis induced by immune checkpoint or BRAF/MEK inhibitors seems to be more frequent in real-world studies than in large phase 3 melanoma trials. Sarcoidosis can mimic metastasis, predominately in mediastinum, representing a diagnostic pitfall. Therefore, biopsies must always be performed to exclude the metastatic spread before initiation of any antineoplastic treatment.

Granulomatous colitis in a patient with metastatic melanoma under immunotherapy: a case report and literature review

BACKGROUND

Immune checkpoint inhibitors (ICPIs) have changed the way advanced malignancies are currently confronted, improving cancer patients' outcomes but also generating distinct immune-related (ir) adverse events. ICPIs-induced colitis is a common complication showing different clinical and histological manifestations. In the literature review, 14 cases with ICPIs related colon granulomas have been reported in 5 studies with either limited or unavailable information regarding histology. Granulomatous reactions can be mistakenly perceived as disease recurrence or progression. Better understanding and identification of this infrequent histological display can help to avoid misdiagnosis and mismanagement.

CASE PRESENTATION

A 63-year-old female patient with metastatic melanoma was admitted to the hospital with symptoms of nausea, persistent diarrhea and shivering fever under consecutive treatments with ICPIs, initially pembrolizumab and subsequently ipilimumab. Sigmoidoscopy was performed revealing mucosal edema, hyperemia and erosions of the rectum and sigmoid colon. Histological evaluation of sigmoid colon mucosa biopsies revealed an unusual colitis pattern characterized by multiple intracryptal granulomas attributed to ICPIs therapy. Steroids were administered and the patient recovered. ICPIs treatment was discontinued. The patient was subsequently treated with chemotherapy but follow up radiology showed disease progression. A re-challenge with another ICPI regimen was decided and the patient is currently under immunotherapy with stable disease regarding melanoma status and without any sign of colitis recurrence.

CONCLUSIONS

The present report provides detailed histological description of a distinctive ICPIs-induced granulomatous colitis and highlights the need for awareness of the distinct adverse events and reaction patterns in the context of immunotherapy.