Dual TMPRSS2:ERG Fusion in a Patient with Lung and Prostate Cancers.

ABSTRACT

The TMPRSS2ERG fusion is considered prostate specific and has been rarely described in other tumors. We describe the case of a patient who developed lung and prostate cancers, both harboring the TMPRSS2ERG fusion. The patient developed a cancer of the prostate with lymph node metastases and after two years a nodule of the thoracic wall. The histology and immunohistochemical profile of the two tumors were typical of prostate and lung cancers. The presence of the TMPRSS2ERG fusion was demonstrated by next-generation sequencing on both malignancies, leading to the assumption that the lung nodule was a metastasis from the prostate cancer. The patient failed to respond to antiandrogen therapy, while chemotherapy for lung cancer led to a significant objective response. To our knowledge, this is the first case of a lung cancer harboring the TMPRSS2ERG fusion, widening the spectrum of lung cancer-associated molecular alterations.