Hiroshi Haneda

EGFR and erbB2 mutation status in Japanese lung cancer patients

Much evidence has accumulated that the epidermal growth factor receptor (EGFR) and its family members are strongly implicated in the development and progression of lung cancers. Somatic mutations of the EGFR gene were found in about 25–40% of Japanese lung cancer patients. More recently, erbB2 mutations are found in about 4% of European‐derived lung cancer patients. We have investigated EGFR and erbB2 mutation status in 95 surgically treated nonsmall cell lung cancer (NSCLC) cases from Nagoya City University Hospital. Seventy‐five adenocarcinoma cases were included. The presence or absence of EGFR and ernB2 mutations of kinase domains were analyzed by reverse transcription polymerase chain reaction (RT‐PCR) amplifications and direct sequences. We have also investigated erbB2 mutation status in 27 surgically treated NSCLC cases followed by treatment with gefitinib from Kinki‐chuo Chest Medical Center. EGFR mutations (CTG→CGG; L858R) were found from 14 of 95 lung cancer patients. We also detected the deletion 1a‐type mutations from 9 patients and deletion 4‐type mutations from 6 patients in exon 19. In exon 20, 4 mutations including 2 novel mutations were found. Total EGFR mutations were present in 35 patients (36.8%). These mutation statuses were significantly correlated with gender (women 73.3% vs. men 20%, p < 0.0001), smoking status (never smoker 69.4% vs. smoker 16.9%, p < 0.0001), pathologic subtypes (adenocarcinoma 45.1% vs. nonadenocarcinoma 12.5%, p = 0.0089) and differentiation status of the lung cancers (well 51% vs. moderately or poorly 18.4%, p = 0.0021). On the other hand, erbB2 mutation was only found from 1 of 95 patients, at exon 20. This patient was female and a never smoker with adenocarcinoma. This 12 nucleotide insertion mutation (2324–2325 ins ATACGTGATGGC) was located in the exon 20 at kinase domain (775–776 ins YVMA). There was no erbB2 mutation in 27 gefitinib‐treated NSCLC patients. In total, we have found only 1 erbB2 mutation from 122 (0.8%) Japanese NSCLC patients. There was a significantly higher erbB2 positive (2+/3+) ratio in EGFR mutant patients (13/25, 52.0%) compared to EGFR wild‐type patients (10/62, 16.1%; p = 0.0247). The NSCLC specimen with erbB2 mutation showed 1+ immunoreactivity. The EGFR mutation status might correlate with the clinicopathologic features related to good response to gefitinib, such as gender, smoking history and pathologic subtypes of lung cancers. However, erbB2 mutation is rare from Japanese lung cancer and is of limited value for molecular target therapy.

Expression of AIRE in thymocytes and peripheral lymphocytes

Autoimmune regulator (AIRE) is a transcription factor expressed in the thymic medullary epithelial cells (MECs). MECs have been suggested to contribute to tolerance induction by presenting tissue specific antigens to T cells that react to these antigens. AIRE expression in cells other than MECs has not been studied extensively. Here we report four-color flow cytometric and quantitative real-time PCR studies on the expression of AIRE in the lymphoid cells in the thymus and periphery. In the thymus AIRE was expressed in B cells and CD4+CD8+ double positive cells at a low level. In the peripheral blood AIRE was expressed in B cells but not in T cells, and also expressed in CD14+ dendritic cells (DCs)/macrophages and granulocytes at higher levels. AIRE mRNA was expressed higher in B cells than in T cells. Further study is warranted to define the functional role of the AIRE expressed in the lymphoid cells.

Epidermal Growth Factor Receptor Gene Mutation and Computed Tomographic Findings in Peripheral Pulmonary Adenocarcinoma

Objective: The presence of epidermal growth factor receptor (EGFR) mutations has been reported to predict the response to gefitinib in pulmonary adenocarcinoma patients. A retrospective analysis was conducted to identify the correlation between computed tomographic findings of the nodules and EGFR status. Patients and Methods: Computed tomographic findings of 38 patients with peripheral pulmonary adenocarcinoma with EGFR mutations were reviewed and compared with those of 42 peripheral pulmonary adenocarcinoma patients with wild-type EGFR. Results: Mutations were found significantly more frequently among women (28 of 45 women versus 10 of 35 men) and among non-smokers (31 of 47 non-smokers and 7 of 33 smokers). The L858R mutation was found in 18 cases. Several types of deletion mutants in exon 19 were found in 18 cases. The nodules with EGFR mutations (2.5 ± 1.0 cm) were significantly smaller in diameter than those in the wild-type group (3.1 ± 1.9 cm). Ground glass opacity (GGO) was more often observed in the mutation group (28 of 38) than in the wild-type group (24 of 42), but the difference was not statistically significant. When mutations were analyzed with reference to both the tumor size and GGO ratio, patients with a tumor ≤3 cm and a GGO ratio ≥50% often had EGFR mutations, and most (10 of 12) were expressed in female patients. No male adenocarcinoma patients with a tumor larger than 4.0 cm had EGFR mutations. Conclusions: EGFR mutations were found most frequently in small peripheral adenocarcinomas with a GGO ratio ≥50%, especially among women. These factors may be useful in deciding therapeutic strategies for adenocarcinomas when resection or biopsy is not feasible.

Preoperative steroid pulse therapy for invasive thymoma : Clinical experience and mechanism of action

Glucocorticoid was used in thymomas. The purpose of the study was to evaluate the efficacy of intravenous high‐dose glucocorticoid (steroid pulse) therapy in patients with previously untreated advanced thymoma. Causes were also sought for a possible underlying mechanism of the effect of steroid on thymoma.

Adjuvant Chemotherapy Based on the In Vitro Histoculture Drug Response Assay for Non-small Cell Lung Cancer Improves Survival

Background: In this study, we analyzed the usefulness of adjuvant chemotherapy for non-small cell lung cancer based on the histoculture drug response assay (HDRA). Methods: From September 2001 to December 2008, 65 patients with pathologic stage II or higher non-small cell lung cancer who underwent surgery received two-cycle HDRA-based adjuvant chemotherapy. Chemosensitivity to cisplatin, carboplatin, paclitaxel, docetaxel, gemcitabine, and irinotecan was examined by the HDRA. All patients were classified according to the number of administered HDRA-positive drugs: the prediction-sensitive group (PSG) (n = 31) comprised patients treated with two HDRA-positive drugs and the prediction-nonsensitive group (PNSG) (n = 34) comprised those treated with a combination of one HDRA-positive and one HDRA-negative drug or two HDRA-negative drugs. The clinical outcomes of the two groups were analyzed. Results: The overall 5-year survival rate of the PSG was 82.4%. On the other hand, that of the PNSG was 40.1%. There were significant differences between the two groups (p = 0.03). The 5-year disease-free survival rate was more favorable in the PSG than in the PNSG (PSG: 56.5%, PNSG: 30.1%, p = 0.05). Multivariate analysis showed that chemotherapy based on the HDRA was a significant prognostic factor (p = 0.03). Conclusions: The prognosis of patients treated with two HDRA-positive drugs was significantly better than that of those treated with one HDRA-positive drug or HDRA-negative drugs. Adjuvant chemotherapy based on the in vitro HDRA may be useful to improve survival in patients who have undergone surgery.

Exon 7 splicing variant of estrogen receptor α is associated with pathological invasiveness in smoking‑independent lung adenocarcinoma

Patients with smoking-independent lung cancer mainly consist of females, yet the molecular background of this epidemiological feature, other than epidermal growth factor receptor (EGFR) mutation, remains unclear. Several studies have revealed the association between female hormone-associated factors and the prognosis of lung cancer, however the data remain inconsistent. The present study focused on the expression of estrogen receptor (ER)α in order to elucidate this association in smoking-independent lung cancer. Immunohistochemistry staining (IHC) of aromatase, ERα and ERβ was performed against formalin-treated tissues from 38 patients who had never-smoked who underwent complete surgical resection between 2012 and 2013. Among them, adequate RNA of the tumor and adjacent normal lung cancer was extracted from 31 matching deep frozen samples. Considering the IHC results, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to measure the expression level of 2 different exons of ERα, exon 6 and exon 7, which are part of the ligand binding domain of ERα, using the Taqman gene expression assay. Extra-nuclear expression of ERα using IHC demonstrated a statistically significant association with pathological invasiveness. RT-qPCR results exhibited a decreased expression of ERα exon 7 in invasive tumor tissues, compared with their adjacent normal tissues. This is consistent with the findings of previous in vitro studies indicating that extra-nuclear ERα were exon 7 splicing variants. No difference was observed in ERα exon 7 expression between normal and tumor tissues in non-invasive lung cancer tissues. When considering the EGFR mutation status, EGFR wild-type lung cancers exhibited decreased ERα exon 7 expression levels compared with EGFR mutated lung cancers. Extra-nuclear expression of ERα, which may represent exon 7 splicing variants of ERα, showed statistical association with pathological invasiveness in smoking-independent lung cancer. The post-translational splicing mechanism of ERα may be involved in the acquired invasiveness of smoking independent lung cancer.

Blastomatoid pulmonary carcinosarcoma: A rare case report and review of the literature: Blastomatoid pulmonary carcinosarcoma

A 65‐year‐old never‐smoking woman presented to a local hospital, because an abnormal shadow was detected at the right lower lung field by annual chest X‐ray. Computed tomography (CT) revealed a 5‐cm tumor in segment 6 of her right lung and an enlarged subcarinal lymph node, suggesting metastasis. The lung tumor was diagnosed as adenocarcinoma by a CT‐guided percutaneous needle biopsy. She was referred to our hospital and underwent right lower lobectomy with lymph node dissection (ND2a‐2). A histopathological examination of the tumor showed a biphasic proliferation made of carcinomatous and sarcomatous components. The carcinomatous component consisted of glandular structures of atypical cells that possessed chromatin‐rich nuclear and clear cytoplasm, confirming high‐grade fetal adenocarcinoma. The sarcomatous component consisted of immature spindle cells that differentiated into chondrosarcoma. Immunohistochemically, the glandular structures expressed membranous beta‐catenin, and the ultimate diagnosis was blastomatoid variant of pulmonary carcinosarcoma. She received four courses of cisplatin plus vinorelbine as adjuvant chemotherapy and remained alive with neither recurrence nor distant metastasis at two and a half years after the operation. We experienced a rare case of blastomatoid pulmonary carcinoasarcoma.

Thymothymectomy with pulmonary partial resection using the subxiphoid approach: how to do it?

An open approach by sternotomy is still selected for locally advanced anterior mediastinal tumors. Technical and instrumental improvements to video-assisted thoracic surgery (VATS) have enabled the treatment of anterior mediastinal tumor in the last decade, and the indications of VATS for an anterior mediastinal tumor are thus expanding. Recently, a single-port thymectomy procedure using the subxiphoid approach has gained popularity worldwide because of its low invasiveness. Improvements to the thoracoscopic instruments and the development of a single-port device are expanding the adoption of single-port VATS in the thoracic surgical field, including resection of anterior mediastinal tumors. We, herein, report a case of thymothymectomy with pulmonary partial resection using the subxiphoid approach. This approach is useful for extended operation for anterior mediastinal tumors and provides favorable results regarding postoperative pain and cosmetic outcomes.

Four immunohistochemical assays to measure the PD-L1 expression in malignant pleural mesothelioma

Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 pathway are expected to be a novel therapy for combating future increases in numbers of malignant pleural mesothelioma (MPM) patients. However, the PD-L1 expression, which is a predictor of the response to ICIs, is unclear in MPM. We studied the PD-L1 expression using four immunohistochemical assays (SP142, SP263, 28-8 and 22C3) in 32 MPM patients. The PD-L1 expression in tumor cells and immune cells was evaluated to clarify the rate of PD-L1 expression and the concordance among the four assays in MPM. The positivity rate of PD-L1 expression was 53.1% for SP142, 28.1% for SP263, 53.1% for 28-8, and 56.3% for 22C3. Nine cases were positive and 10 were negative for all assays. Discordance among the four assays was found in 13 cases. The concordance rates between SP142 and 22C3 and between 28-8 and 22C3 were the highest (84.4%). The concordance rates between SP263 and the other three assays were low (71.9% to 75.0%). The PD-L1 expression in MPM was almost equivalent for three of the assays. Given the cut-off values set in our study, these findings suggested that these assays, except for SP263, can be used for accurate PD-L1 immunostaining in MPM.

A comparative study of PD-L1 immunohistochemical assays with four reliable antibodies in thymic carcinoma

Currently, four immunohistochemical assays are registered with the US Food and Drug Administration to detect the expression of PD-L1. We investigated the PD-L1 expression in thymic carcinomas using these four diagnostic assays. The cases of 53 patients were reviewed and their specimens were subjected to four PD-L1 assays with different antibodies (SP142, SP263, 22C3, and 28-8). The PD-L1 expression in tumor cells (TCs) and immune cells (ICs) was evaluated. In TCs, the four assays showed similar scores in each case. Histopathologically, high TC scores were observed in squamous cell carcinomas (SqCCs). Meanwhile, there were no significant relationships among the IC scores in the four assays. In SqCCs, the high expression of PD-L1 (defined as ≥50% TC score) in TCs tended to be associated with early stage cancer. The patients with high expression levels of PD-L1 tended to show longer overall survival in the 22C3 assays (p=0.0200). In thymic carcinomas, the staining pattern showed high concordance among the four assays when TCs – rather than ICs – were stained. High PD-L1 positivity in TCs, especially in SqCCs, indicated that PD-1/PD-L1 targeted therapy may be a promising therapeutic approach.