RESUMO
Primary lung carcinoma tumors possessing a signet-ring cell carcinoma (SRCC) component at varying proportions are rare, while those primarily composed of an SRCC component are much rarer. Reported here is a case of primary lung adenocarcinoma primarily composed of an SRCC component with a scant acinar component that developed in an 81-year-old male. Approximately 95% of the adenocarcinoma was occupied by an SRCC component that was shown to be diastase-resistant based on positive periodic acid-Schiff staining. Immunostaining for ALK and fluorescence in situ hybridization analysis (break-apart assay) showed the presence of an ALK gene rearrangement. Findings in this case indicated a primary lung adenocarcinoma with ALK gene rearrangement, in which an SRCC component accounted for approximately 95% of the tumor.
RESUMO
Primary pulmonary malignancies are one of the most common malignancies worldwide. The most common non-small cell lung malignancy is adenocarcinoma, but there are many subtypes with different molecular and genetic expressions causing different manifestations. Uncommon manifestations include persistent back pain and tracheal bronchial tumors. More than 95% of reported tracheal bronchial tumors are benign and thus are rarely biopsied. There are no reported cases of secondary tracheal bronchial tumors due to pulmonary adenocarcinoma. Today, we are reporting the first case report of an uncommon manifestation of primary pulmonary adenocarcinoma.