Four synchronous primary tumors in a male patient.

Multiple primary malignancies are defined as two or more primary malignant tumors diagnosed in one individual; they are further classified to synchronous or metachronous based on the period between each cancer diagnosis and the other. The diagnosis of four synchronous cancers is exceedingly rare. We report a case of a 72-year-old man, diagnosed with synchronous quadruple cancers, Hurthle cell carcinoma and papillary carcinoma of the thyroid, as well as squamous cell carcinoma and carcinoid tumor of the lung.