In accordance with the publication of the eighth version of the "General rules for clinical and pathological record of lung cancer", which was edited by The Japan Lung Cancer Society, the "Practical guidelines for lung cancer screening" were also revised. More than 30 years have passed since these practical guidelines were first published. Thus, many issues related to lung cancer screening have been greatly improved, including the digitization of chest X-ray examinations, the spread of low-dose chest CT screening and the establishment of a social consensus about the quality assurance and the efficacy of cancer screening. There have also been significant legal and administrative developments. However, some new problems have also appeared. Thus, our committee, The Committee for Lung Cancer Screening of The Japan Lung Cancer Society, has drastically revised the "Practical guidelines for lung cancer screening", especially in regard to cancer screening in the workplace, chest X-ray digitization, low-dose chest CT screening, further examinations for sputum cytology-positive cases, informed consent, the efficacy of lung cancer screening, and quality assurance in lung cancer screening. In this article, the background and aims of this revision have been described in detail. We hope that this paper will contribute to the improvement of quality assurance in lung cancer screening in the future.

Objective. Pleomorphic carcinoma of the lung is a histological type that was first proposed in 1999. This tumor is rare and accounts for approximately 1.6-2.6% of all cases of lung cancer; thus, to date, few studies have described the clinical course of surgical cases. Methods. The characteristics, treatments, histological parameters, and outcomes of 13 patients with pleomorphic carcinoma of the lung who underwent pulmonary resection at Tohoku University from 2007 to 2013 were studied. Results. The ages of the patients ranged from 41 to 84 years (mean, 67 years; male, n=9; female, n=4). Lobectomy and partial resection were performed for 11 (bilobectomy, n=1) and 2 patients, respectively. Seven patients experienced postoperative recurrence within 6 months; 5 of the 7 patients died. Disease-free survival ranged from 38 to 2,801 days (median, 562 days). One patient with single brain metastasis at the time of the initial diagnosis underwent pulmonary resection and received gamma knife treatment. Relapse was observed at the supraclavicular lymph node and was treated with chemotherapy. A complete response was achieved, and this patient remains alive without evident disease at 1,816 days. Conclusion. Although pleomorphic carcinoma of the lung has a poor prognosis and the efficacy of chemotherapy in treating it is unclear, our results indicate that a sub-section of the population may show a good prognosis.

Background. In general, thoracic surgeons should be very careful when indicating pneumonectomy for patients who are over seventy years of age. However, in the clinical setting, there are elderly patients who require pneumonectomy to survive. We report a case in which an octogenarian required left pneumonectomy because of an oncological emergency. Case. An 80-year-old man was admitted to our hospital in an emergency state due to acute dyspnea and left dull chest pain. Chest X-ray and CT revealed a left hilar mass. We diagnosed the mass as locally advanced left hilar lung cancer; the patient's situation represented an oncological emergency due to severe hypoxia. We performed emergent left pneumonectomy with the resection of the pericardium. The post-operative course was very good and he could be discharged at 7 days after surgery. Conclusion. Pneumonectomy was feasible for an octogenarian with an oncological emergency.

Background. Lymphomatoid granulomatosis is classified as a "lymphoproliferative disease" in the General Rule for Clinical and Pathological Record of Lung Cancer. It is a rare disease and its concept, pathogenesis and treatment are yet to be clearly established. Case. The patient was a 63-year-old woman at the time of her first visit to our hospital. In July 2009, an upper gastrointestinal series showed an abnormality. Biopsies were obtained by upper gastrointestinal endoscopy; however, no diagnosis could be made. Thereafter, the gastric lesion spontaneously regressed. In January 2015, computed tomography (CT) revealed multiple lung masses and abdominal lymphadenopathy. In March 2015, thoracoscopic partial resection of the left lower lobe was performed for diagnostic purposes, and a histopathological examination of the resected specimen revealed features that were consistent with a diagnosis of lymphomatoid granulomatosis. A review of the gastric biopsy specimens showed similar histopathological features, suggesting that the gastric lesion was also a part of the same pathological process as lymphomatoid granulomatosis. In October 2015, CT revealed multiple nodular shadows in the lungs and liver, and combination chemotherapy was started in November 2015. In January 2016, 3 courses of chemotherapy had been completed and the lesions in the lungs, liver and lymph nodes had decreased in size (partial response). Conclusion. There are few reported cases of lymphomatoid granulomatosis with gastric lesions; thus, our case can be considered rare. When selecting treatment, it should be kept in mind that lymphomatoid granulomatosis lesions are not necessarily limited to the lung.

Background. The recommended primary therapy for ALK-positive lung cancer is crizotinib. While remains effective for a long time for some patients, it eventually becomes ineffective and leads to an enlargement of the tumor in many other patients. Case. The patient was a 71-year-old woman who was diagnosed with pulmonary adenocarcinoma in 2012 (cT2aN3M1b, stage IV, ALK-positive). During chemotherapy, several cystic lesions without contrast enhancement were found on contrast-enhanced cranial MRI and their progress was observed. After chemotherapy became ineffective in May 2013, the treatment was changed to the oral administration of crizotinib, which resulted in the shrinkage of the primary lesion. Nine months from the start of crizotinib treatment, the patient's cerebral lesions were enlarged, while the primary lesion was observed to have shrunk. Craniotomy was therefore performed to conduct a biopsy. The definitive diagnosis of the biopsy specimen was metastasis to the brain from pulmonary adenocarcinoma. After whole brain irradiation, an exacerbation of bone metastasis occurred and the oral administration of alectinib was initiated in September 2014. A significant reduction of the metastatic lesions was observed on contrast-enhanced cranial MRI at one month after the start of alectinib treatment and the tumor reduction effect continues to be effective at 19 months after the start of alectinib treatment. Conclusion. In this case, alectinib was effective for treating brain metastasis for which crizotinib was ineffective. This is partly because there is a difference in the degree of transitivity of both drugs to the central nervous system. Moreover, because metastasis to the brain from mucinous tumors may provide atypical imaging findings--as occurred in this case--sufficient observation and a definitive histology-based diagnosis are vital.

Background. Renal cell carcinoma rarely causes solitary pleural metastasis without pulmonary involvement. We report the case of a patient with solitary pleural metastasis of papillary renal cell carcinoma who presented with massive pleural effusion. Case. A 66-year-old man with dyspnea and general fatigue was transferred to our hospital to undergo a detailed examination. He had been exposed to asbestos in his workplace and had been undergoing hemodialysis for 23 years due to renal failure as a result of chronic glomerulonephritis. Chest and abdominal computed tomography scans revealed massive left pleural effusion without any pulmonary lesions and a mass in the right kidney, suggesting renal cell carcinoma, lung cancer, or malignant mesothelioma. Aspiration cytology of the pleural effusion revealed atypical cells with macronucleoli or atypical multinucleated cells, but a cell-block immunohistochemical examination did not confirm the histology. The patient's condition progressively deteriorated, and he died of a worsening of chronic renal failure on the 10th day after admission. Autopsy revealed a mass in the right kidney and left-dominant thickening of the pleura, which was covered with multiple nodules. Immunohistochemical examinations of these nodules confirmed solitary pleural metastasis of papillary renal cell carcinoma. Conclusion. Physicians need to be aware of pleural metastasis of extra-pulmonary tumors and try to confirm it histologically, even in patients with a history of asbestos exposure and malignant pleural effusion.

Background. Lung adenocarcinoma can acquire resistance during therapy with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). This resistance is attributed to a second mutation of the EGFR gene in the majority of cases. However, the transformation to small cell carcinoma is another mechanism known to induce therapy resistance, although it is much less frequent. Case. A 73-year-old man was diagnosed with lung adenocarcinoma (cT4N2M1a, stage IV) with an EGFR mutation and treated with gefitinib as first-line therapy. The cancer exhibited a good response to the therapy. While the primary lesion stayed well-controlled, an elevated serum level of neuron-specific enolase (NSE) and liver tumors were newly detected. A liver biopsy to identify the origin of the tumors revealed small cell lung cancer (SCLC) with an EGFR mutation. Our findings suggested that the lung adenocarcinoma had transmutated to SCLC. The liver metastases decreased in size after the administration of chemotherapeutic agents for SCLC. Conclusion. When adenocarcinoma acquires resistance to EGFR-TKI therapy, the prediction and diagnosis of transformation to SCLC markedly helps optimize the therapeutic strategy. Therefore, if the lesion size and serum tumor markers indicate this specific transformation, a repeated biopsy should be strongly considered following the evaluation of risks and other conditions.

Background. Large-cell neuroendocrine carcinoma is a relatively unusual histological type of primary lung cancer, and tonsillar metastasis from lung cancer is rare. Case. A 52-year-old man with a history of pharyngalgia for 1 month was referred by a local practitioner to our hospital for workup. After a further examination at the otorhinolaryngological department, he was diagnosed with oropharyngeal cancer in the right palatine tonsil (undifferentiated type, cT2N2b). Positron emission tomography/computed tomography was performed to detect possible distant metastases and revealed a 20-mm nodule on the bullar wall in the right upper lobe. Although synchronous double cancer was possible, an endobronchial biopsy was difficult to perform because of the bulla. We prioritized treatment for the pharyngeal tumor rather than the lung tumor because he also had dysphagia from the tonsillar tumor. After chemoradiotherapy, he was referred to our department to undergo surgery. Thoracoscopic right upper lobectomy and mediastinal lymph nodes dissection were performed, and his postoperative course was uneventful. The pathological diagnosis of the lung nodule was large-cell neuroendocrine carcinoma. Immunohistochemical staining of the biopsy from the tonsillar tumor showed a pattern similar to that of the lung tumor. Therefore, we determined that the patient had a tonsillar metastasis from the lung cancer. Eighteen months after chemoradiotherapy, he remained stable without additional treatment. Conclusion. We encountered a rare case of large-cell neuroendocrine carcinoma of the lung with tonsillar metastasis. Treating these lesions as synchronous double cancer was successful and associated with a relatively good outcome.