A 45-year-old Caucasian female with insignificant past medical history was diagnosed with a cutaneous malignant melanoma of the right femoral region. The primary lesion was resected and histology demonstrated a superficial spreading melanoma of Breslow thickness 3.2 mm, with ulceration. She then underwent a wide resection of the primary lesion as well as right inguinal sentinel lymph node excision. Wide resection margins were negative, whereas the sentinel lymph node was infiltrated. As a result, the patient underwent right inguinal lymph node dissection, which identified lymph node metastases in 2 out of 7 lymph nodes. Clinical examination and computed tomography (CT) of the brain, chest, abdomen, and pelvis did not reveal findings suggestive of distant metastatic disease. The pathology stage by American Joint Committee on Cancer (AJCC) (7th edition) was pT3b, N2a, M0 (stage IIIB). In addition, molecular tumor analysis showed a BRAFV600E mutation.
The patient was started on adjuvant treatment with dabrafenib at a dose of 150 mg, twice daily and trametinib at a dose of 2 mg, once daily. During the first three months of treatment, she experienced recurrent episodes of low-grade fever, accompanied by nodular panniculitis of both lower limbs, which resolved after temporary treatment interruption. Following this, the drugs were well tolerated, with no evidence of disease recurrence; the patient discontinued treatment after a total treatment duration of 12 months. At CT restaging upon discontinuation, multiple, enlarged mediastinal lymph nodes were identified without pulmonary parenchymal lesions. In contrast, in previous restaging CT scans performed every three months while on treatment, no such lesions were present. The patient underwent bronchoscopy and transbronchial biopsy of a mediastinal lymph node. Histology revealed the presence of noncaseating epithelioid granulomas, suggestive of a sarcoid-like reaction (Figure 1). Complete blood count and biochemistry were normal. Serum angiotensin-converting enzyme was also normal. A QuantiFERON-TB Gold assay was negative. The patient remained asymptomatic, did not receive treatment, and during a 3-month follow-up, a CT scan showed regression of mediastinal lymphadenopathy and no evidence of melanoma metastases.