Necrotizing Skin and Soft Tissue Infection Mimicking Cutaneous Metastasis in Lung Cancer

Abstract

Cutaneous metastases occur in 0.7–9% of cancer patients, most commonly from lung cancer in men. When present in lung cancer (1–12% of cases), they indicate poor prognosis with a mean survival of 5–6 months. More often, necrotizing skin and soft tissue infections (NSSTIs) are seen, though they can be diagnostically challenging and can result in delays in treatment. We present a 61-year-old man with newly diagnosed non-small cell lung cancer (NSCLC) and a two-week history of a necrotic abscess on his chest. Following incision and drainage of an 8 x 8 cm cavity, his condition worsened. CT revealed a spiculated lung mass extending into the chest wall, raising concern for cutaneous metastasis. However, cultures grew Streptococcus constellatus and Actinomyces odontolyticus; blood cultures also revealed S. constellatus. With further investigation into the patient’s history, it was discovered that the patient had poor dentition and recent full dental extraction. With targeted antibiotics, he improved and was discharged. This case highlights the importance of having high suspicion for commonly encountered microorganisms in the appropriate setting. Given the risk of rapid decompensation, patients suspected of having NSSTI should be evaluated for evidence of both local complications, hematogenous spread, and initiation of timely treatment, including source control and appropriate antimicrobial therapy.