An analysis of residual lung volume changes after segmentectomy based on three-dimensional computed tomography.

Background: Based on the results of JCOG0802 and CALGB studies, segmentectomy has considered to be a standard procedure for early-stage non-small cell lung cancer (NSCLC). After lobectomy, the residual cavity is filled with mediastinal and diaphragmatic deviations, and compensatory volume changes are present in the residual lungs. In this study, we examined the efficacy of segmentectomy, a surgical procedure, by focusing on its impact on postoperative lung volume and function. Methods: We enrolled 77 patients who underwent segmentectomy as their initial surgical procedure, excluding those with additional lung resections and those who lacked postoperative computed tomography imaging. The predicted residual volume (mL) was defined as the total lung volume before surgery minus the volume of the resected area. Using the predicted residual volume (mL) and postoperative total lung volume (mL), we calculated the rate of postoperative lung volume increase [(postoperative total lung volume/predicted residual volume) × 100] (%). We also classified 52 cases with a rate of postoperative lung volume increase of ≥100% into a compensatory group, while those with a rate of <100% were classified into a non-compensatory group. Results: The average postoperative lung volume increase was 104.6% among 77 cases. Age ≥65 years, pack year index ≥27.5, ≥3 resected segments, and use of electrocautery for intersegmental plane division were significantly associated with compensatory group classification. In 20 compensatory cases with preoperative and postoperative pulmonary function tests, postoperative vital capacity and forced expiratory volume in one second values exceeded the preoperative predictions. This study further examined the areas responsible for postoperative compensatory lung volume increase. In the compensatory group, significant expansion was observed in the ipsilateral lobes, excluding the resected segment and contralateral lung, while no significant changes were noted in the volume of the lobe, including the resected segment. Conversely, the non-compensatory group showed a significant volume decrease in the resected lobe, but no significant increase in other areas. Conclusions: This study emphasizes the importance of preserving lung segments in segmentectomy. The study demonstrates extensive compensatory volume changes in the ipsilateral lung and contralateral lung. There was no significant volume decrease in any residual segment. This underlines the potential of segmentectomy to maintain lung function and expand treatment options post-surgery. In addition, the compensated group included patients with a lower pack-year index and younger patients. These results suggest that postoperative compensatory lung expansion includes not only hyperinflation of the remaining lung, but also an increase in the functional lung parenchyma.

EGFR-mutated lung adenocarcinoma with choroidal oligometastasis during treatment with gefitinib: a case report.

The patient was a 74-year-old woman who was diagnosed with lung adenocarcinoma, clinical Stage IIIA. Induction chemoradiation was performed followed by right upper lobectomy and lymph node dissection. Because of positive pleural effusion cytology, which was proven after surgery, the patient was diagnosed with pathological Stage IVA with EGFR L858R mutation. At 17 months after the administration of gefitinib, left choroidal metastasis appeared. Stereotactic irradiation and ruthenium small-beam radiation were effective; however, the metastatic lesion showed regrowth 7 months after these treatments. Because the patient's choroidal oligometastasis was resistant to conservative therapy, left ophthalmectomy was performed. EGFR mutations (L858R and E709K) were detected in the resected choroidal tumor. The patient continued to take gefitinib. However, a neoplastic lesion developed on the optic nerve adjacent to the resected posterior eye segment. The lesion was treated with stereotactic radiation, gefitinib was switched to afatinib 30 mg, and the patient remains alive and disease free for 11 months.

Low FDG uptake in lung metastasis despite high FDG uptake in a primary adenoid cystic carcinoma of a sublingual gland.

Adenoid cystic carcinoma is a rare malignant tumor that primarily occurs in the salivary glands. There are few reports of sublingual gland adenoid cystic carcinoma with lung metastases on which 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) was performed. We report the case of a 57-year-old Japanese woman with an adenoid cystic carcinoma of the sublingual gland with lung metastases in whom the FDG uptake of the lung metastasis was low despite high FDG uptake in the primary lesion. The pathological examination revealed that solid components were more visible and the Ki-67 index was more positive in the primary lesion compared to the metastatic lesion. We speculate that differences in tumor growth ability might have resulted in the differences in FDG uptake. This case demonstrates that significant differences might occur in the FDG uptake between primary and metastatic tumors.

Role of Pathologic Single-N and Multiple-N Descriptors in Resected Non-Small Cell Lung Cancer.

BACKGROUND: The eighth edition of lung cancer N staging assignment includes the location of lymph node metastasis, but does not include single-N and multiple-N descriptors. RESEARCH QUESTION: Do the single-N and multiple-N statuses stratify the prognosis of patients with non-small cell lung cancer (NSCLC)? STUDY DESIGN AND METHODS: Using the National Cancer Database, we analyzed patients with pathologically staged N1 and N2 NSCLC. N descriptors were classified into pathological single N1 (pSingle-N1), pathological multiple N1 (pMulti-N1), pathological single N2 (pSingle-N2), and pathological multiple N2 (pMulti-N2). Survival analysis was performed using the Kaplan-Meier method and multivariable Cox regression models. RESULTS: In the general analysis cohort, 24,531, 22,256, 8,528, and 21,949 patients with NSCLC demonstrated pSingle-N1, pMulti-N1, pSingle-N2, and pMulti-N2 disease, respectively. Patients with pMulti-N1 and pMulti-N2 disease showed a shorter survival than those with pSingle-N1 and pSingle-N2 disease, respectively (hazard ratio [HR], 1.22 [P < .0001] for N1 and 1.39 [P < .0001] for N2). After adjusting age, sex, and histologic findings, the HR for pSingle-N2 compared with pMulti-N1 disease was 1.05 (P = .0031). Patients with pN1 disease were categorized by metastatic lymph node count (1, 2, 3, ≥ 4), showing significant prognostic differences among groups (P < .0001). In the sensitivity analysis cohort (limited to R0 resection, lobectomy, or more; survival ≥ 30 days; ≥ 10 examined lymph nodes; and without neoadjuvant therapy; n = 34,904) and the external validation cohort (n = 708), analyses supported these results. INTERPRETATION: Patients with NSCLC with one metastatic lymph node, whether in N1 or N2 stations, showed better survival than those with more than one lymph node involved. Patients with NSCLC with a single-skip N2 lymph node metastasis showed survival similar to patients with multiple N1 lymph nodes, and the number of lymph nodes involved in N1 resections up to four or more was sequentially prognostic.