A sufficiently large tissue sample is required to perform next-generation sequencing (NGS) with a high success rate, but the majority of patients with advanced non-small-cell lung cancer (NSCLC) are diagnosed with small biopsy specimens. Biopsy samples were collected from 184 patients with bronchoscopically diagnosed NSCLC. The tissue surface area, tumor cell count, and tumor content rate of each biopsy sample were evaluated. The impact of the cut-off criteria for the tissue surface area (≥1 mm2) and tumor content rate (≥30%) on the success rate of the Oncomine Dx Target Test (ODxTT) was evaluated. The mean tissue surface area of the transbronchial biopsies was 1.23 ± 0.85 mm2 when small endobronchial ultrasonography with a guide sheath (EBUS-GS) was used, 2.16 ± 1.49 mm2 with large EBUS-GS, and 1.81 ± 0.75 mm2 with endobronchial biopsy (EBB). The proportion of samples with a tissue surface area of ≥1 mm2 was 48.8% for small EBUS-GS, 79.2% for large EBUS-GS, and 78.6% for EBB. Sixty-nine patients underwent ODxTT. The success rate of DNA sequencing was 84.1% and that of RNA sequencing was 92.7% over all patients. The success rate of DNA (RNA) sequencing was 57.1% (71.4%) for small EBUS-GS (n = 14), 93.4% (96.9%) for large EBUS-GS (n = 32), 62.5% (100%) for EBB (n = 8), and 100% (100%) for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) (n = 15). Regardless of the device used, a tissue surface area of ≥ 1 mm2 is adequate for samples to be tested with NGS.

Background: The Oncomine Dx Target Test (ODxTT) is a next-generation sequencing-based companion diagnostic test which has been recently developed; however, its analysis success rate could be improved, especially for small samples. The aim of this study was to identify the pathological factors associated with biopsy specimens that affect the analysis success rate of ODxTT. Methods: We retrospectively investigated 119 cases subjected to ODxTT at Kanagawa Cancer Center. Data pertaining to the results of BRAF V600E mutation analysis in ODxTT and pathological factors based on microscope slides were collected. Pathological factors including tissue surface area, tumor cell count, and tumor content rate were assessed. We constructed receiver operating characteristic curves and determined the optimal cutoff values of each pathological factor. Multivariate logistic analysis was used to identify significant factors. Results: A total of 98 of 119 samples were successfully analyzed (75.6%). The tissue surface area and tumor cell count were significantly higher in the group associated with analysis success (P < 0.001 and P = 0.011, respectively), and their optimal cutoff values were 1.04 mm 2 and 375 cells, respectively. A tissue surface area > 1.04 mm 2 and tumor cell count >375 cells had a positive effect on the analysis success rate of ODxTT (odds ratio [OR] 0.10; 95% confidence interval [CI]: 0.03-0.35; P < 0.001 and OR 0.25; 95% CI: 0.07-0.90; P = 0.033, respectively). Conclusions: Selecting samples with a tissue surface area > 1.04 mm 2 and a tumor cell count >375 cells might improve the analysis success rate of ODxTT. Key points: Significant findings of the study: We found that a tissue surface area > 1.04 mm 2 and tumor cell count >375 cells had a positive effect on the analysis success rate of ODxTT in the analysis of biopsy tissue samples. What this study adds: It is sometimes necessary to assess genetic alterations with a small biopsy sample in daily practice. The criteria mentioned above will help to determine which tests should be performed, ODxTT or multiple single-gene testing.

A 75-year-old woman visited a nearby clinic with complaints of right clavicle discomfort, and she underwent diagnostic thoracoscopic lung biopsy, being diagnosed with lung metastasis and a right-upper mediastinal mass. The superior mediastinum mass was extrapulmonary and covered by the pleura, and it was not biopsied. Papillary thyroid carcinoma was diagnosed following biopsy of the lung metastasis. Only a small tumor, with a maximum diameter of 70 mm from the right neck to the superior mediastinum, in the thyroid gland invades the internal jugular vein and subclavian vein, forming a tumor embolus in the right brachiocephalic vein and reaching the vicinity of the superior vena cava. For life-saving purposes, we obtained approval from the Cancer Board of Kanagawa Cancer Center and used lenvatinib according to unresectable undifferentiated cancer IRB approval number 28–41. The tumor had shrunk after 4 months, and surgery was performed. The postoperative course has been good, and the patient is being followed up. The patient is alive three months after surgery, and lung metastases have disappeared on CT images. This case is reported as a successful case of neoadjuvant chemotherapy and interval debulking surgery.

A sufficient amount of tissue sample is required to perform next-generation sequencing (NGS) with a high success rate, but the majority of patients with advanced non-small-cell lung cancer (NSCLC) are diagnosed with small biopsy specimens. Biopsy samples were collected from 184 patients with bronchoscopically diagnosed NSCLC. The tissue surface area, tumor cell count, and tumor content rate of each biopsy sample were evaluated. The impact of the cut-off criteria for the tissue surface area (&ge; 1 mm2) and tumor content rate (&ge; 30%) on the success rate of Oncomine Dx Target Test (ODxTT) was evaluated. The mean tissue surface area of the transbronchial biopsies was 1.23 &plusmn; 0.85 mm2 when small endobronchial ultrasonography with a guide sheath (EBUS-GS) was used, 2.16 &plusmn; 1.49 mm2 with large EBUS-GS, and 1.81 &plusmn; 0.75 mm2 with endobronchial biopsy (EBB). The proportion of samples with a tissue surface area of &ge; 1 mm2 was 48.8% for small EBUS-GS, 79.2% for large EBUS-GS, and 78.6% for EBB. Sixty-nine patients underwent ODxTT. The success rate of DNA sequencing was 84.1% and that of RNA sequencing was 92.7% over all patients. The success rate of DNA (RNA) sequencing was 57.1% (71.4%) for small EBUS-GS (n = 14), 93.4% (96.9%) for large EBUS-GS (n = 32), 62.5% (100%) for EBB (n = 8), and 100% (100%) for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) (n = 15). Regardless of the device used, a tissue surface area of &ge; 1 mm2 is adequate for samples to be tested with NGS.

Background: Bronchopleural fistula (BPF) remains a serious complication after surgery for lung cancer with bronchial resection. A free pericardial fat pad (FPFP) is applied in high-risk cases to reduce BPF frequency. BPF may occur 6 months after surgery. Thus, we evaluated the residual FPFP volume at 6 months after surgery to estimate the residual FPFP ratio and determine the amount of FPFP to be harvested during surgery. Methods: We retrospectively investigated 40 patients who underwent lobectomy with bronchial stump coverage using FPFP. During surgery, the volume of the harvested FPFP was measured and the FPFP was affixed to the bronchial stump. Further, 6 months after surgery, the residual volume of the installed FPFP was analyzed using a three-dimensional volume analyzer and the residual ratio was calculated. We also evaluated clinicopathological factors influencing the resected FPFP and residual ratio. Results:The median resected FPFP volume was 11 mL. During multivariate analysis, body mass index and surgical approach were found to be significant factors associated with the resected FPFP volume.The median residual FPFP volume was 4.3 (0.4-15.5) mL. The median residual ratio was 0.39 (0.13-0.66).The resected FPFP volume was significantly associated with the residual volume (P<0.001) but not with the residual ratio (P=0.811). No factor was associated with the residual ratio. Conclusions: In all cases, residual FPFP was confirmed at 6 months after surgery and the residual ratio was 40%. It is necessary to determine the volume of FPFP to be harvested while carefully considering the shrinkage ratio.