A case of idiopathic multicentric Castleman's disease with secondary autoimmune neutropenia.

A 73-year-old Japanese woman with productive cough and dyspnoea on exertion was admitted, and she showed neutropenia and pulmonary reticular opacities and axial and mediastinal lymphadenopathies on chest computed tomography. The clinical findings and surgical lung and lymph node biopsies were diagnostic for idiopathic multicentric Castleman's disease (iMCD) complicated by secondary autoimmune neutropenia (AIN). iMCD is often complicated with hematologic disorders, however, iMCD complicated with AIN has not been reported; therefore, if iMCD is accompanied by neutropenia, the anti-neutrophil antibodies should be measured.

A rare case of double primary lung adenocarcinomas with uncommon complex EGFR G719X and S768I mutations and pleomorphic carcinoma.

Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-targeted therapy has emerged as a viable treatment for patients with advanced non-small cell lung cancer with common EGFR mutations. The uncommon G719X and S768I mutations can co-occur as complex mutations in the same tumor. Here we report a case of a 72-year-old male patient with double lung carcinoma, with G719X and S768I complex mutations detected in the right upper lung lobe along with brain metastases. Osimertinib (80 mg/day) was administered as the first-line treatment, and a reduction in the right lobe tumor and brain lesions was achieved. However, the left upper lung lobe mass remained unchanged; histopathological examination via a lobectomy revealed pleomorphic carcinoma. Thus, the patient was diagnosed with multiple primary lung cancers. In conclusion, osimertinib is a viable treatment option for lung cancer with rare EGFR G719X and S768I complex mutations.

Successful Treatment with Crizotinib to Overcome Drug Resistance Possibly Due to Mesenchymal-epithelial Transition Amplification in a Lung Cancer Patient with the Echinoderm Microtubule-associated Protein-like 4-anaplastic Lymphoma Kinase Fusion Gene.

Amplification of the mesenchymal-epithelial transition (MET) gene plays an important role in anticancer drug resistance to anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs) in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK)-rearranged lung cancer cells. We encountered an ALK-rearranged lung cancer patient who developed MET amplification after alectinib treatment and showed an effective response to fifth-line crizotinib. First-line alectinib treatment was effective for 2.5 years; however, liver metastases exacerbated. Liver biopsy specimens revealed MET and human epidermal growth factor receptor 2 (HER2) amplifications. Switching to the MET inhibitor crizotinib improved liver metastases. Crizotinib may be effective in ALK-positive patients with MET amplification.

Autopsy case of a patient with rapidly progressive combined small-cell lung carcinoma with spindle-shaped cell tumor.

A 69-year-old Japanese man visited our hospital because of worsening shortness of breath. His chest computed tomography (CT) showed a giant left lung mass with a massive left pleural effusion. He could not be treated with chemotherapy and eventually died from a rapidly progressive tumor. He was diagnosed with combined small cell lung carcinoma (C-SCLC) with spindle-shaped cell tumor at autopsy. C-SCLC is characterized by pathologically concurrent SCLC and adenocarcinoma or squamous cell carcinoma, or rarely, spindle-shaped cell tumor. The clinical course of C-SCLC with spindle-shaped cell tumor has not previously been determined. Our patient's tumor increased by 2.59-fold in 20 days. The combination of C-SCLC with spindle-shaped cell tumor suggested rapid progression and a poor prognosis.

Advanced lung adenocarcinoma detected by choroidal metastasis in a patient with amyopathic dermatomyositis: A case report.

A 63-year-old Japanese man with amyopathic dermatomyositis treated with immunosuppressants became aware of distortion of his left visual field, and a metastatic choroidal tumor was suspected. His chest computed tomography (CT) showed a pulmonary nodule in the right upper lobe and mediastinal lymphadenopathy, and he was diagnosed with advanced lung adenocarcinoma with choroidal metastasis. Malignancies associated with dermatomyositis (DM) are often rapidly progressive and, in choroidal metastasis associated with lung cancer, a choroidal lesion is often diagnosed prior to lung cancer; therefore, CT performed at the time of diagnosis of choroidal metastasis may show lung cancer lesions. When ocular symptoms are observed in DM patients, metastatic malignancies should be suspected, and systemic examinations, such as positron emission tomography (PET)-CT, should also be performed.