Our patient had metastatic melanoma in the lungs. The differential of “cannon ball” lesions in the lungs includes metastatic disease, infection, vasculitis, autoimmune disorders and sarcoid.
The most common malignancies associated with cannon ball lesions are: renal cell ca, choriocarcinoma, endometrial carcinoma, prostate cancer, colon cancer, and synovial sarcoma. While these are the most common; any cancer can produce lung nodules.
While tuberculosis classically presents in the upper lobes, in immunosuppressed patients including diabetics it can present as nodules. Histoplasmosis, cryptococcosis , nocardia , and echinococcus can all present as nodules.
Wegener’s, is often diagnosed by c-ANCA . These are antibodies to proteinase 3 and myeloperoxidase which occur in 90% of patients with Wegener’s. Necrotic nodules can be found in the lungs. Sarcoid and rheumatoid nodules can also appear as lung nodules.
Kshatriya R, Patel V, Chaudhari S, Patel P, et al. Cannon ball appearance on radiology in a middle-aged diabetic female. 2016. Lung India. Sep-Oct 33(5):562-568.
Wheat LJ, Kaufmann C. Histoplasmosis. Infect Dis Clin N Am 2003;17:1-19.
Vohra P, Sharma M, Yadav A, Chaudhary U. Nocardiosis: A review of clinic-microbiological features, Int J Life Sci Biotechnol Pharma Res. 2013;2:20-29.