Upfront skeletal muscle metastases from non-small cell lung carcinoma: Report of an extremely rare occurrence detected by 18F-fluorodeoxyglucose positron emission computed tomography scan

Abstract

Adenocarcinoma lung with upfront metastases to skeletal muscle is rarely encountered in clinical practice since skeletal muscles are highly resistant to dissemination from solid organs. Moreover, these muscle metastatic lesions generally present with pain and palpable mass to get detected clinically. However, silent skeletal muscle metastases without any symptoms or signs getting detected by functional imaging with whole body 18F-fluorodeoxyglucose positron emission/computed tomography (18FDG-PET/CT) scan have been scarcely described in literature, while we present such an interesting case in a 45-year-old female. She was diagnosed as a case of biopsy-proven metastatic adenocarcinoma lung after evaluation by 18FDG-PET/CT. Despite treatment with palliative chemoradiotherapy, her disease progressed, and she finally succumbed to her illness. This case is discussed to highlight an unusual scenario we encountered, the clinical course of the disease with its management and overall poor prognosis.

An Unusual Case of Lung Adenocarcinoma Metastasis to the Tricep Muscle: Four Years Disease-Free After Surgical Resection and Radiotherapy

“…Lesions have also been reported in the orbit and pectoral muscles [7][8][9][10]. Besides, some literature also reports the calf muscles being among the common spreading sites [11]. Diagnosing metastasis to the skeletal muscles can be confusing as the symptoms can be misunderstood as muscle strain or injury.…”

Skeletal muscle metastases of hepatocellular carcinoma: A case report and literature review

“…Kim et al [ 32 ] proposed that surgical resection or external radiotherapy should be considered for isolated masses without other metastases to reduce pain and mass effect. However, Purkayastha et al [ 33 ] reported a case of lung adenocarcinoma with left gluteus muscle metastasis in which acute metastasis of the lower back, bilateral supraspinatus muscle, and psoas muscle occurred after three cycles of personal computer chemotherapy and subsequent low-dose external radiotherapy. These clinical cases suggest that more clinical practice studies are needed for the diagnosis and treatment of SMM.…”