Impact of intrapulmonary tumour location of non-small-cell lung cancer on surgical outcomes for segmentectomy.

OBJECTIVES: While segmentectomy is considered a viable option for small peripheral non-small-cell lung cancer, its efficacy for central lesions remains uncertain. This study aimed to assess the oncological outcomes of segmentectomy for central lesions compared to peripheral ones. METHODS: We retrospectively examined 338 clinical stage IA non-small-cell lung cancer patients who underwent thoracoscopic anatomical segmentectomy at our institution from January 2013 to December 2021. Patients were divided into 2 groups based on intrapulmonary tumour location: inner two-thirds (central group, n = 82) and outer one-third (peripheral group, n = 256). RESULTS: The gender, body mass index, performance score, smoking, comorbidities and preoperative pulmonary function were similar in both groups. On computed tomography images, tumour diameter and consolidation-to-tumour ratio were comparable between the groups. The central group had significantly greater tumour-to-pleura distances [mm, 23 (18-27) vs 11 (8-14); P < 0.001], shorter margin distances [mm, 20 (15-20) vs 20 (20-20); P < 0.001] and larger resected lung volumes based on subsegment count [4 (3-6) vs 3 (3-5); P = 0.004] than the peripheral group. Surgery duration, bleeding, hospitalization or drainage period, mortality, readmission and pathological stage were equivalent between the groups. The central group showed significantly more postoperative pleural effusions (5% vs 1%; P = 0.03) than the peripheral group, with no adverse impact on postoperative pulmonary functions. During the follow-up period, local-only recurrence rates were 0% and 8% in the respective groups (Gray test P = 0.07), and total recurrence rates were 6% and 11% (Gray test P = 0.70), with no significant differences. Moreover, no significant inter-group difference in overall survival rates was observed (82% vs 93%; P = 0.15). CONCLUSIONS: Segmentectomy may be a promising therapeutic option for early-stage non-small-cell lung cancer located in the inner two-thirds of the parenchyma.

Lobectomy versus proton therapy for stage I non-small cell lung cancer.

OBJECTIVE: Lobectomy is the standard treatment for patients with early-stage non-small cell lung cancer (NSCLC). In recent years, an increasing number of patients with lung cancer have been treated using proton therapy (PT). We conducted a propensity score-matched analysis to compare the treatment outcomes of these 2 modalities. METHODS: We retrospectively reviewed data from 275 patients with histologically confirmed clinical stage I NSCLC who underwent lobectomy (n = 206) or PT (n = 69) at our institution from July 2013 to December 2020. The end points were overall survival (OS), cause-specific survival, recurrence-free survival (RFS), local control, regional lymph node control, and distant control. Propensity score matching was performed to reduce selection bias in the 2 groups. RESULTS: The matched cohort consisted of 59 patients who underwent lobectomy and 59 patients who underwent PT with a median follow-up period of 50 months. There were no significant differences in OS (P = .26), cause-specific survival (P = .33), RFS (P = .53), local control (P = .41), regional lymph node control (P = .98), and distant control (P = .31). In the lobectomy and PT groups, the 5-year OS rate was 85.8% and 79.1%, respectively, the RFS rate was 82.3% and 77.8%, and the local control rate was 92.1% and 96.6%. CONCLUSIONS: We found no difference in survival or disease control between lobectomy and PT in patients with histologically confirmed clinical stage I NSCLC. Despite these findings, the potential for unmeasured confounding factors remains, and randomized control trials are needed to better compare these treatment modalities.

Factors related to fixedness after transbronchial fiducial marker placement for image-guided proton therapy: A retrospective study.

BACKGROUND: The usefulness of transbronchially inserted gold fiducial markers has been reported in radiation therapy and proton therapy for mobile lesions, such as lung tumors. However, there is occasional dropout of inserted markers. This retrospective study investigated the factors related to dropout of markers inserted for image-guided proton therapy (IGPT). METHODS: Between June 2013 and October 2021, 535 markers were inserted in 171 patients with lung tumors. We investigated whether marker dropout was affected by the location of marker insertion, distance between the marker and the chest wall (DMC), and difference in forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC). Marker dropout from the time of planning computed tomography (CT) to follow-up CT was also evaluated. RESULTS: Of the 535 inserted markers, 417 were confirmed on planning CT and 356 on follow-up CT after IGPT. Multivariate analysis revealed that marker insertion into the upper lobe and FEV1/FVC ≥70% were factors associated with total marker dropout. Marker dropout between planning CT and follow-up CT was associated with DMC, FEV1/FVC ≥70%, and planning CT performed within 4 days of marker insertion. CONCLUSIONS: Marker dropout can be minimized by inserting markers more peripherally, by considering the planned insertion location, and FEV1/FVC. Additionally, planning CT should be scheduled at least 5 days after marker insertion.

Thoracoscopic Anatomical Sublobar Resection Including Subsegmentectomy for Non-Small Cell Lung Cancer.

BACKGROUND: Among anatomical sublobar resection techniques for non-small cell lung cancer (NSCLC), the clinical benefit of subsegmentectomy remains unclear. We investigated whether anatomical sublobar resection including subsegmentectomy-segmental resection with subsegmental additional resection or subsegmental resection alone-is an effective and feasible surgical procedure for NSCLC. METHODS: We retrospectively reviewed data of 285 patients with clinical stage I NSCLC who underwent anatomical sublobar resection at our institution from January 2013 to March 2021 and compared surgical outcomes between patients who underwent anatomical sublobar resection including (IS; n = 50) and excluding (ES; n = 235) subsegmentectomy. RESULTS: No significant intergroup differences were noted in terms of age, sex, smoking, comorbidities, tumor size or location, consolidation tumor ratio, and preoperative pulmonary function. The IS group had more preoperative computed tomography-guided markings (34 vs. 15%; p = .004) and smaller resected lung volumes converted to the total subsegment number [3 (2-4) vs. 3 (3-6); p = .02] than the ES group. No significant differences in margin distance [mm, 20 (15-20) vs. 20 (20-20); p = .93], readmission rate (2% vs. 3%; p > .99), and intraoperative (8% vs. 7%; p = .77) or postoperative (8% vs. 10%; p = .80) complication rates were observed, and the 5-year local recurrence-free survival (91% vs. 90%; p = .92) or postoperative pulmonary function change were comparable between both groups. CONCLUSIONS: Although further investigations are required, anatomical sublobar resection including subsegmentectomy for clinical stage I NSCLC could be an acceptable therapeutic option.

A case of resected pulmonary capillary hemangioma with a literature review.

Pulmonary hemangiomas are benign, relatively rare tumours. Because computed tomography (CT) findings show a variety of images, it is often difficult to distinguish hemangiomas from lung cancer and other benign tumours. We report a 63-year-old man who was diagnosed with a pulmonary capillary hemangioma (PCH). A right lung basal segmentectomy was performed for diagnosis and treatment. On chest CT, the lesion was shown to be a solid nodule with contrast-enhanced margins. This finding was thought to reflect the dense vascular hyperplasia of the central part of the tumour based on the pathologic findings. Although few studies involving PCH have referred to contrast-enhanced CT, the findings of contrast-enhanced CT might be a valuable indicator for diagnosing PCH.

Everolimus in combination with octreotide LAR in thymic atypical carcinoid.

Thymic atypical carcinoids are extremely rare tumors and have a poor prognosis owing to their aggressive clinical course. The efficacy of treatments other than complete surgical resection is unclear. We herein report a postoperative recurrent case of thymic atypical carcinoid treated with everolimus and octreotide long-acting repeatable (LAR). A 75-year-old woman was admitted to our department because a nodule was detected in the right lobe of thymus by annual computed tomography. The patient underwent thymothymectomy, and a diagnosis of thymic atypical carcinoid was made. One year and seven months after surgery, she developed multiple metastases in the lung, hilar and mediastinal lymph nodes, liver, and bone. Everolimus 10 mg/day was administered; however, the dose had to be reduced to 5 mg/day due to grade 3 hyperglycemia and grade 3 interstitial lung disease. Metastatic lesions other than liver metastasis markedly responded to everolimus, although the liver metastases gradually progressed. Three years and six months after surgery, she was administered octreotide LAR 30 mg per month in combination with everolimus. She has maintained stable disease for 8 months after the application of this combination therapy.

A single-center analysis of 71 patients with thymic carcinoma: the chronological changes in the surgical procedure and prognosis.

Background: Effective treatments for thymic carcinoma (TC) have not been established due to its rarity and the prognosis has not yet been improved. In the present study, data of patients who underwent treatment for TC at our single institution were retrospectively reviewed to investigate the chronological changes in the clinical characteristics, surgical procedure, and prognosis. Methods: A total of 71 patients were included in this study. To investigate the chronological changes, the patients were divided into two groups at January 2009, when minimally invasive surgery (MIS) for thymic epithelial tumors (TETs) was introduced. Results: Among the 71 TC patients, 24 patients underwent surgery through December 2008 (earlier period), and 21 underwent surgery from January 2009 (later period). The patients in the later group were more likely to be diagnosed by chest computed tomography (CT) scan without subjective symptom. The rates of MIS and complete resection were significantly higher and the number of the patients at the early stage were significantly greater in the later group. The 5-year overall survival (OS) rate of the patients who underwent surgery at earlier and later groups were 58.7% and 92.8% respectively (P<0.01). Conclusions: The prognosis of TC has improved over time, thanks to early detection by CT screening and complete surgical resection.

Preoperative percutaneous needle indigo carmine and lipiodol mixture marking in lung segmentectomy.

OBJECTIVES: For successful nodule localization and appropriate surgical margin distances in pulmonary segmentectomy for patients with lung malignancies, the effectiveness and feasibility of preoperative marking using an indigo carmine and lipiodol mixture remain unclear. METHODS: Patients who underwent thoracoscopic pulmonary segmentectomy with (marking group, n = 69) and without (non-marking group, n = 265) preoperative marking at our institution from January 2013 to March 2020 were retrospectively reviewed and compared in terms of surgical outcomes. All markings were performed using a fine needle to percutaneously inject an indigo carmine and lipiodol mixture under the guidance of computed tomography fluoroscopy. RESULTS: Successful localization was achieved in 66 (96%) patients, of whom 62 (94%) underwent dye pigmentation and 4 (6%) underwent intraoperative fluoroscopy. On images, the marking group showed a significantly longer distance between the lung surface and tumour [mm, 9 (1-17) vs 0 (0-10); P < 0.01] and smaller maximum tumour size [mm, 16 (11-21) vs 17 (13-23); P = 0.03] and consolidation tumour ratio [0.4 (0.3-1) vs 0.8 (0.4-1); P < 0.01] than the non-marking group. Both groups had comparable operative outcomes, perioperative complications, pulmonary function changes and surgical margin distances [mm, 20 (15-21) vs 20 (15-20); P = 0.96] without any local recurrence on the surgical margin. Propensity score-matching analysis also showed similar findings for both groups. CONCLUSIONS: Thoracoscopic pulmonary segmentectomy with preoperative marking using an indigo carmine and lipiodol mixture may be an acceptable therapeutic option for small malignancies located in deep lung parenchyma.

Complex video-assisted thoracoscopic surgery lobectomy for locally advanced lung cancer: a prospective feasibility study.

PURPOSE: The limitations regarding indications for video-assisted thoracoscopic surgery lobectomy requiring complex surgery remain unclear. A prospective cohort study was conducted to elucidate the safety and feasibility of complex thoracoscopic lobectomy for patients with locally advanced non-small-cell lung cancer. METHODS: We planned to enroll patients who were suspected of needing thoracoscopic lobectomy or more with complex surgery, including tracheo-bronchoplasty, pulmonary arterioplasty, and combined resection of adjacent organs. Between February 2016 and January 2019, 28 consecutive patients were prospectively enrolled. RESULTS: After excluding 1 patient due to disease progression, 27 patients were included in this study. Three patients underwent thoracoscopic lobectomy without complex surgery. Of the remaining 24 patients, complex thoracoscopic lobectomy was successfully completed in 21 (88%), and the 3 conversions were due to surgery for the great vessels. All 27 patients achieved complete resection. Six patients (22%) suffered grade 2 complications, and the in-hospital, 30-day, and 90-day mortality rates were all 0%. At a median follow-up time of 900 days, the 3-year overall and disease-free survival rates were 75% and 54%, respectively. CONCLUSIONS: Complex thoracoscopic lobectomy was shown to be safe and feasible in select patients with locally advanced non-small-cell lung cancer excluding invasion to the great vessels. CLINICAL REGISTRATION NUMBER: University Hospital Medical Information Network Clinical Trials Registry, 000,019,441 (JAPAN). Institutional Review Board number: 46-15-0003 (accepted at September 7, 2015).

Comparison of surgical outcomes between thoracoscopic anatomical sublobar resection including and excluding subsegmentectomy.

OBJECTIVES: Despite the ubiquitous utilization of anatomical sublobar resection for malignant lung tumors, the effectiveness and feasibility of subsegmentectomy remains unclear. This study therefore compared the perioperative outcomes between anatomical sublobar resection including (IS) and excluding (ES) subsegmentectomy. METHODS: Patients who had undergone anatomical sublobar resection at our institution from January 2013 to March 2019 were retrospectively reviewed. Clinicopathologic characteristics and perioperative outcomes of the IS group (n = 58) were then analyzed the compared to those of the ES group (n = 203). RESULTS: No statistically significant differences in age, sex, comorbidities, tumor location, preoperative pulmonary function, or tumor size on imaging were found between both groups. The IS group had significantly higher preoperative computed tomography-guided marking rates (40% vs. 18%; p < 0.01) and used significantly more staplers for intersegmental dissection than the ES group [4, interquartile range (IQR): 3-4 vs. 3, IQR: 3-4; p = 0.03]. Both groups had comparable 30-day mortality (0% vs. 0%; p > 0.99), intraoperative complications (7% vs. 10%; p = 0.61), and postoperative complications (5% vs. 8%; p = 0.58). After propensity score matching, the IS group experienced significantly lesser blood loss than the ES group (5 mL, IQR: 1-10 vs. 5 mL, IQR: 5-20; p = 0.03). Both groups experienced no local recurrence and demonstrated similar postoperative pulmonary functions after surgery. CONCLUSIONS: IS may be a feasible and acceptable therapeutic option for malignant lung tumors. Nonetheless, future investigations are required to further validate the current findings.

Mixed-type primary germ cell tumor of the mediastinum in a young adult male with a sudden life threatening condition: A case report.

Primary germ cell tumors of the mediastinum are rare neoplasms. Above all, choriocarcinomas are highly aggressive with early haematogenous dissemination. Here, we report an extremely rare case of mixed-type primary germ cell tumor of the mediastinum which occurred in a 26-year-old man with multiple metastases of the lung caused by choriocarcinoma components, with diffuse pulmonary hemorrhaging. The patient developed a sudden life threatening condition a few days after a needle biopsy. KEY POINTS: Significant findings of the study: This was an extremely rare case of mixed-type germ cell tumor in a young adult male who developed a sudden life threatening condition due to choriocarcinoma components just a few days after a needle biopsy. What this study adds: Serious conditions may occur in patients with germ cell tumor containing choriocarcinoma components. At present, there is no other way to treat such patients than to promptly recognize complications and perform urgent multimodal intervention.

Talc pleurodesis for secondary pneumothorax in elderly patients with persistent air leak.

BACKGROUND: We herein report the usefulness of two types of talc pleurodesis for secondary pneumothorax of elderly patients with persistent air leak who have severe pulmonary emphysema. METHODS: We assessed 17 elderly patients with persistent air leak who received talc pleurodesis for secondary pneumothorax from April 2013 to March 2017. Thoracoscopic talc poudrage (TTP) (n=11) was performed in patients whose general condition was thought to sufficiently stable to tolerate for general anesthesia. Talc slurry pleurodesis (TSP) (n=6) via a chest tube was performed in patients whose general condition was thought to be insufficiently stable to tolerate general anesthesia. RESULTS: The median drainage period after pleurodesis was 6 days in patients who received TTP and 12 days in patients who received TSP. Complications associated with talc pleurodesis included atrial fibrillation (n=1) in the thoracoscopic poudrage group, while the slurry pleurodesis group showed chest pain (n=2), asthmatic attack (n=1), and pneumonia (n=1). All patients who received thoracoscopic poudrage were able to leave the hospital after removal of the chest tube. Five of the six patients who received slurry pleurodesis were able to leave the hospital, but one of them died of acute exacerbation of interstitial pneumonia (IP) on the 45th day after pleurodesis. The success rate was 94% (16/17). There were no cases of recurrence during the observation period. CONCLUSIONS: TTP was deemed likely to be safe and effective for patients able to tolerate general anesthesia. In patients with IP, especially those treated with steroids, the indication of talc pleurodesis should be cautiously considered.

Case of intercostal lung hernia with hemosputum that developed after thoracoscopic lobectomy.

Intercostal lung hernia is defined as a protrusion of the lung tissue through a chest wall defect. It is an uncommon condition after a lobectomy, and most cases are asymptomatic. We herein report a case of intercostal lung hernia after a thoracoscopic right upper lobectomy in a patient whose chief complaint was hemosputum. Elevated intrathoracic pressure is a major risk factor for intercostal lung hernia. In this patient, obesity and bronchial asthma were considered the causes of this disease. Three reports on intercostal lung hernia after thoracoscopic lobectomy were previously published. In three of the four lung hernia cases (including our own), right upper lobectomy had been performed, and the middle lobe was herniated. We consider right upper lobectomy to be an anatomical risk factor.

Thymic inflammatory pseudotumor with multilocular thymic cyst caused by immunoglobulin G4-related disease.

A 44-year-old man was referred to our hospital after an anterior mediastinal tumor was noted on computed tomography during follow-up observation after left testicular seminoma resection. Chest computed tomography revealed an enhanced mass measuring 33 x 16 x 15 mm at the anterior mediastinum. Chest magnetic resonance imaging revealed high signal intensity on T2-weighted imaging, and F18 fluorodeoxyglucose-positron emission tomography showed a maximum standardized uptake of 12.45. Laboratory tests revealed no elevated tumor markers, except for mildly elevated interleukin-2. Based on these results, complete resection was performed under suspicion of a malignant tumor, mediastinal metastasis of seminoma, or malignant lymphoma. An extended thymectomy with partial merger pericardial resection was performed using a subxiphoid approach. Small nodules and multiple thymic cysts were observed the thymus in addition to the main mass. Microscopic examination of the tumor revealed fibrosis, lymphocyte infiltration with lymphoid follicular hyperplasia, and hyperplasia of the thymus. Numerous immunoglobulin G4 (IgG4)-positive plasma cells were found on immunohistochemical staining. The ratio of IgG4 to total IgG was approximately 60%. We ultimately diagnosed the patient with a thymic inflammatory pseudotumor with multilocular cyst caused by IgG4-related disease.

Long-term outcomes of video-assisted thoracoscopic surgery lobectomy vs. thoracotomy lobectomy for stage IA non-small cell lung cancer.

OBJECTIVES: Video-assisted thoracoscopic surgery (VATS) lobectomy is performed widely for patients with clinical stage I non-small cell lung cancer (NSCLC) because of its superior short-term outcomes to those of thoracotomy lobectomy. However, the long-term outcomes of VATS lobectomy vs. thoracotomy lobectomy remain controversial. METHODS: We reviewed the clinical data of 202 consecutive patients who underwent lobectomy for clinical stage IA NSCLC at our institution between January, 2008 and December, 2013. Stage IA NSCLC was confirmed pathologically in 162 of these patients, 60 of whom underwent VATS lobectomy and 102 of whom underwent thoracotomy lobectomy. We compared the perioperative clinical factors and outcomes of these two groups, using a propensity score-matched analysis. RESULTS: In an analysis of 58 matched cases, the VATS group showed less blood loss, a shorter duration of chest tube placement, a shorter postoperative hospital stay, and a lower peak C-reactive protein value, despite a longer operative time. The VATS group also had significantly longer survival than the thoracotomy group [5-year overall survival, 100% vs. 87%, respectively (p = 0.01); 5-year disease-free survival, 100% vs. 86% (p = 0.03)]. CONCLUSIONS: These findings suggest that VATS may have better long-term as well as short-term outcomes than thoracotomy for patients with early-stage NSCLC.

Pure red cell aplasia associated with thymoma: a report of a single-center experience.

BACKGROUND: Pure red cell aplasia (PRCA) associated with thymoma is relatively rare, and relevant reports are limited. We investigated the clinical features and outcomes of PRCA associated with thymoma in this study. METHODS: A retrospective review of all PRCA patients who underwent surgical resection of thymoma from April 1, 2004, to December 31, 2015, was performed. RESULTS: We experienced eight patients with PRCA among 146 patients who underwent surgical resection of thymoma. Extended thymectomy (n=4) and thymectomy (n=4) were performed for thymoma. Regarding the WHO classification of thymoma, the subtypes were type B2 or B3 in seven patients, and the stage of thymoma was advanced in seven patients. Complete resection was achieved macroscopically in only five patients. Recurrence of thymoma occurred in four patients who underwent complete resection. PRCA was diagnosed after surgical resection of thymoma in six patients (range 1-101 months, median 56.5 months). Cyclosporine was used for PRCA in six patients. Pneumonia of treatment-related complications due to cyclosporine occurred in all patients. The follow-up period ranged from 13-147 months (median 54.5 months) after the PRCA diagnosis. Three patients obtained complete remission of anemia by cyclosporine. Although one patient was able to stop taking cyclosporine because of complete remission of anemia, transfusion was needed due to relapse of PRCA. Five patients died, with the main causes of death diagnosed as pneumonia (n=4) and cardiac failure (n=1). CONCLUSIONS: PRCA associated with thymoma was diagnosed postoperatively in three-quarter of patients. We should be alert for the occurrence of PRCA even after resection of thymoma, especially in patients with incomplete resection or advanced disease. Cyclosporine was effective for PRCA, but treatment-related complications occurred, particularly pneumonia. As treatment for PRCA associated with thymoma and its complications were combined in a complex manner, treating PRCA associated with thymoma can be quite difficult.

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

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.

Early chest tube removal after thoracoscopic lobectomy with the aid of an additional thin tube: a prospective multi-institutional study.

OBJECTIVES: There is no evidence concerning the appropriate drainage volume for indicating chest tube removal after pulmonary lobectomy. A prospective multi-institutional cohort study was designed to elucidate the safety of early chest tube removal after thoracoscopic lobectomy. METHODS: Between April 2009 and November 2011, 310 patients with suspected or histologically documented lung cancer were screened. Patients without air leakage or bloody, chylous, or purulent pleural effusion underwent chest tube removal on the day after thoracoscopic lobectomy, independent of the drainage volume. The subjects were classified into three groups as tertiles according to the drainage volume that was observed for approximately 24 h after surgery. The associations between the drainage volume and the development of complications were investigated, with several clinical factors taken into account. RESULTS: The 162 patients who were enrolled underwent early chest tube removal via this protocol and were classified into three groups according to their drainage volume (0-219 mL, n = 52; 220-349 mL, n = 56; and ≥ 350 mL, n = 54). A 7F backup tube placed within the dead space to prevent troubles was removed by postoperative day 4 in all patients because nothing happened. Univariate and multivariate analyses showed that the drainage volume was not associated with the risk of complications. CONCLUSIONS: Early removal of the chest tube on the day after thoracoscopic lobectomy appears to be a safe treatment protocol in patients without air leakage or bloody, chylous, or purulent pleural effusion; however, careful surveillance is needed for patients who have a drainage volume of ≥ 350 mL/day. CLINICAL REGISTRATION NUMBER: University Hospital Medical Information Network Clinical Trials Registry, 000028971 (Japan).

The relationship between the expression of thymidylate synthase, dihydropyrimidine dehydrogenase, orotate phosphoribosyltransferase, excision repair cross-complementation group 1 and class III ß-tubulin, and the therapeutic effect of S-1 or carboplatin plus paclitaxel in non-small-cell lung cancer.

Previous studies have reported that the expressions of specific proteins may predict the efficacy of chemotherapy agents for non-small cell lung cancer (NSCLC) patients. The present study evaluated the expression of proteins hypothesized to be associated with the effect of chemotherapeutic agents in 38 NSCLC patients with pathological stage II and IIIA. The subjects received carboplatin plus paclitaxel (CP) or S-1 as adjuvant chemotherapy following complete resection. The protein expressions evaluated were those of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and orotate phsphoribosyltransferase (OPRT), which were suspected to be associated with the effect of S-1 agents, excision repair cross-complementation group 1 (ERCC1), which was suspected to be associated with the effect of platinum-based agents, and class III ß-tubulin (TUBB3), which was suspected to be associated with the effect of taxane-based agents. The positive rate of TS was 55.3% (n=21/38), DPD was 57.9% (n=22/38), OPRT was 42.1% (n=16/38), ERCC1 was 47.4% (n=18/38) and TUBB3 was 44.7% (n=17/38). Among the patients who received S-1 adjuvant chemotherapy, TS-negative cases demonstrated a significantly better disease-free survival than positive cases. Thus, TS protein expression may have been a factor that predicted the effect of S-1 agent as adjuvant chemotherapy.