Transition From Distinct Types of KRAS Mutation-Harboring Multifocal Lung Adenocarcinoma to Rhabdoid Tumor: A Longitudinal Follow-Up.

BACKGROUND Rhabdoid tumor (RT) of the lung is a rare and aggressive malignancy. The origin of and the mutation responsible for RT are entirely unknown. The distinction between RT associated with subtypes of lung cancer and SMARCA4-deficient thoracic sarcomas is also unknown. CASE REPORT Three pulmonary subsolid nodules in the right S6, left S6, and left S8 were identified in a 78-year-old Japanese woman. At 3 and 9 months later, a chest CT showed unchanged sizes, but at 15 months the development of a 37-mm mass in the right S6 was observed. The patient's systemic condition deteriorated rapidly, and she died 1 month later. An autopsy revealed that the mass consisted of 90% RT and 10% lung adenocarcinoma. There were another 2 adenocarcinoma lesions in the left lung. KRAS mutation analyses revealed the same KRAS mutation (G12D) in the adenocarcinoma and RT components in the identical mass and metastatic RT, indicating that all of these components had the same clonality. A different KRAS mutation in each of the 3 adenocarcinoma lesions was detected (right S6: G12D, left S6: A59G, left S8: G12C), indicating that the multiple adenocarcinoma lesions were truly multifocal lung adenocarcinoma. The adenocarcinoma and RT components retained SMARCA4 expression. CONCLUSIONS This is the first evidence of RT originating from multifocal lung adenocarcinoma. KRAS mutation is thought to be responsible for the RT's emergence via the epithelial-mesenchymal transition. Patients with multiple subsolid nodules should be followed closely; aggressive surgical intervention should be considered given concerns about the evolution of this aggressive malignancy.

A case of bilateral invasive mucinous adenocarcinoma of the lung with severe productive cough and dyspnea successfully treated with palliative lung lobectomy.

Invasive mucinous adenocarcinoma (IMA) of the lung is a chemo-refractory type of lung cancer with frequent intrapulmonary dissemination. Patients with IMA of the lung often suffer from a productive cough and rapid deterioration of performance status (PS). There is currently no standard therapeutic strategy against this unrelenting condition. Here we report a patient with bilateral IMA of the lung with severe productive cough and dyspnea successfully controlled by palliative lung lobectomy. A 67-year-old Japanese man presented with a 3-month history of productive cough. Chest computed tomography (CT) revealed a mass lesion in the left lower lobe and a small nodule and multiple thin-walled cystic lesions in the right lung. He was diagnosed with stage IIB IMA of the lung. Over the next two weeks, his productive cough and dyspnea drastically worsened and his PS declined from 0 to 4. Chest CT showed increases in size of both the nodule and cystic lesions in the right lung and the mass lesion in the left lower lobe. He was re-diagnosed as stage IVA. Given the extreme heterogeneity of the tumor distribution, we decided to perform palliative resection of the left lower lobe. After the surgery, he experienced complete relief of respiratory symptoms, and his PS improved dramatically, enabling chemotherapy. Thirty-one months after surgery, he maintains good PS. In conclusion, our report suggests that aggressive introduction of palliative lung lobectomy played a substantial role for in the excellent outcome of our patient with relatively well confined, advanced-stage IMA.

Successful treatment of steroid-refractory double-positive ANCA and anti-GBM disease with a combination of plasma exchange and immunosuppression: A case report and literature review.

The concurrence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and anti-glomerular basement membrane (GBM) disease, known as double-positive disease, is rare, but it occurs at a much higher frequency than expected by chance. Double-positive disease has an aggressive clinical course, with no optimal treatment strategy. Here we describe a patient with steroid-refractory double-positive disease who was treated successfully with the addition of plasma exchange (PE) and cyclophosphamide (CPA). A 78-year-old Japanese woman who was diagnosed with diffuse alveolar hemorrhage and rapidly progressive glomerulonephritis received two cycles of pulse steroid therapy. However, her respiratory and renal condition deteriorated. She was found to be positive for both myeloperoxidase-ANCA and anti-GBM antibodies. The combination of PE and CPA improved her systemic condition. This is the first case report of a patient with steroid-refractory double-positive disease who was successfully treated with the addition of PE and CPA. The marked contrast in therapeutic response to corticosteroids alone and the addition of PE and CPA in this case strongly implies that earlier induction of combination therapy aimed at rapid removal of pathogenic autoantibodies and prevention of ongoing antibody production might improve the outcome of this life-threatening disease.