Background: The authors report on an extremely rare case of skeletal muscle metastasis from primary lung cancer that involved the radial nerve and humerus, which was ‘over-treated’ with wide tumour resection and frozen autograft reconstruction upon misdiagnosis of sarcoma by intraoperative frozen section, amid pressure of expediting hospital care in a low-resource setting during the coronavirus disease (COVID-19) pandemic.

Case presentation: A 61-year-old male living outside Metro Manila presented with painful mass in his left distal arm during the enhanced community quarantine, and requested admission upon testing negative for COVID-19. Imaging studies suggested a diagnosis of soft tissue sarcoma involving the radial nerve and humerus, and intending to prevent nosocomial severe acute respiratory syndrome coronavirus 2infection of patient, treatment was expedited by foregoing biopsy and opting for intraoperative frozen section prior to resection. Frozen section findings suggested malignancy intraoperatively, and surgical team proceeded with wide tumour resection and frozen autograft reconstruction of the humerus using plates and screws. However, permanent sections revealed metastatic carcinoma from primary non-small cell lung cancer, with positron emission tomography (PET) scan confirming lung mass in the right apical lobe.

Conclusion: The report concludes that establishment of a definite tumour diagnosis by final histopathological analysis is indispensable, even when planning for emergent surgery in the time of the COVID-19 pandemic.