A female underwent a right middle lobectomy for a pulmonary adenocarcinoma (AD). She eventually died of a right malignant pleural mesothelioma (MPM; sarcomatoid type) 4 years and 7 months after the removal of the AD even though she did not have any history of asbestos exposure, smoking, or radiation exposure. Her chest CT revealed multiple pulmonary nodules and bilateral pleural effusion with a right pleural tumor directly invading into the abdominal cavity. The genomics of tumor origin and characteristics were examined for the AD and the MPM. As a result, 50 somatic variants were detected in the AD, and 29 somatic variants were detected in the MPM. The variants which were common in both the AD and the MPM were not present, which suggested that the AD and the MPM had occurred independently in different origins. The MPM had two driver oncogenes of TP53 and EP300, but the AD did not. Two driver oncogenes of TP53 and EP300 were hypothesized to make the MPM aggressive. The speed at which the MPM progressed without the patient having a history of asbestos exposure, smoking, or radiation exposure was alarming.

Carcinoma of unknown primary site (CUP) is diagnosed only in 2-9% of all cancer cases. Adenocarcinomas account for approximately 60% of CUP, and some of these are putative lung adenocarcinomas. The frequency of driver oncogene positivity in the putative lung adenocarcinomas is unknown, and the efficacy of targeting therapies for the driver oncogene is also unknown. This is the first case report of C-ros oncogene 1 (ROS1)-rearranged putative lung adenocarcinoma presenting as CUP showing a good response to ROS1 inhibitor therapy. A 55-year-old woman presented with neck lymphadenopathy. Computed tomography and [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed swelling of the bilateral supraclavicular, left accessory, mediastinal, and abdominal lymph nodes. The pathological analysis of the lymph node specimen biopsy indicated adenocarcinoma with cytokeratin 7 and thyroid transcription factor-1 positivity. Thus, this case was identified as ROS1- rearranged putative lung adenocarcinoma presenting as CUP. Oral crizotinib, an ROS1 inhibitor, was administered at a dose of 250 mg twice daily. Four weeks later, several swollen nodes showed marked improvement, and eight weeks later, FDG PET showed almost no uptake. In conclusion, putative lung adenocarcinoma presenting as CUP may involve ROS1 rearrangement, and ROS1 inhibitor therapy may be effective.

Wilms tumor or nephroblastoma is a common kidney malignant tumor in childhood, accounting for ~5% of all pediatric tumors. At present, reports on Wilms\' tumor occurring in adults, particularly at ages >30 years, are extremely rare. The majority of the cases of adult Wilms\' tumor are closely associated with chemotherapy. Furthermore, in rare cases, Wilms\' tumor is characterized by three classic types of cells, namely blastemal, stromal and epithelial cells. We herein report a case of Wilms\' tumor with three classic types of cells on histological examination in a 51 year-old male patient who had received prior chemotherapy. The patient promptly underwent radical nephrectomy and remains alive. A review of previously presented cases of adult Wilms\' tumor from PubMed database was also performed.