Ruxolitinib as monotherapy in a patient with anaplastic lymphoma kinase positive lung adenocarcinoma.

We present unusual treatment outcome in a 59-year-old male diagnosed with metastatic lung adenocarcinoma with a very good response to ruxolitinib as monotherapy. In June 2017, this patient was diagnosed with myeloproliferative neoplasm - Janus-associated kinases 2 positive - and in December 2017 ruxolitinib therapy was started. At the same time, patient was diagnosed with lung adenocarcinoma in the left lower lobe with positive anaplastic lymphoma kinase mutation and with right lower lobe metastasis. Because of partial regression of tumor size noted on the computed tomography (CT) scans during tumor investigation, we did not apply any therapy for lung adenocarcinoma. A follow-up CT scan done in March 2018 showed further size reduction of tumor lesion in lower left lobe (91%), while follow-up CT scan done in June 2018 showed further size reduction of tumor lesion in lower right lobe (82%).