Diffuse lesions secondary to sarcoidosis mimicking widespread metastatic breast cancer: A case report

Sarcoidosis With Multiple Bone Lesions Mimicking Advanced Lung Cancer With Multiple Bone Metastases

Bone lesions in sarcoidosis are more common than previously known. A 59-year-old female with a history of sarcoidosis was referred due to suspected lung cancer. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) revealed numerous bone lesions in addition to abnormal uptake by pulmonary nodules and mediastinal lymph nodes, which mimicked metastatic advanced lung cancer. Biopsy of bone lesions detected epithelioid cell granuloma consistent with bone sarcoidosis. Moreover, prednisolone treatment was tried to exclude malignant disease. One month after prednisolone administration, bone lesions and other abnormal uptake disappeared on PET/CT. Bone sarcoidosis is often asymptomatic and is discovered incidentally as multiple lesions that may require differentiation from malignant disease. Biopsy of bone lesions and administration of corticosteroids may be useful for accurate diagnosis.

Sarcoidosis Mimicking a Malignant Metastatic Disease

Sarcoidosis can have pulmonary and extrapulmonary clinical manifestations depending on the organ of involvement. Because multiple organs are involved by the disease, sarcoid can mimic metastatic diseases. Whenever clinical and radiological clues of metastasis are present, differentials other than cancer should not be missed. Herein, we present a case of a middle aged gentleman who presented to the oncology clinic for 1-month history of low back pain associated with a dry cough along with radiological findings of metastatic disease involving the lungs, liver, lymph nodes, axial spine, and adrenal gland. A biopsy of the liver lesion showed non-caseating granuloma. Elevated blood levels of angiotensin-converting enzyme confirmed the diagnosis of sarcoidosis.

Atezolizumab-Induced Sarcoidosis-Like Reaction in a Patient with Metastatic Breast Cancer

Tumor-related sarcoidosis-like reactions (SLR) have been reported with the use of immune checkpoint inhibitors (ICIs). We report a case of 50-year-old woman who observed an enlarged lymph node in the right hilar region and the appearance of a subcutaneous mass in the extremities during chemotherapy with atezolizumab plus nab-paclitaxel for metastatic triple-negative breast cancer (TNBC). Skin biopsy revealed the formation of epithelioid granulation species with the Langhans giant cell. After discontinuing atezolizumab in the treatment procedure, the hilar lymph nodes and the subcutaneous mass were reduced. A pathological examination was effective in differentiating tumor exacerbation from SLR. Owing to limited information on ICI-related SLR in breast cancer, future studies are recommended to properly manage immune-related adverse effects during cancer treatment.