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.

Prognostic value of systemic inflammatory markers and the nutrition status in thymic epithelial tumors with complete resection

Background

Recent studies have shown that several systemic inflammatory markers and the nutrition status, including the neutrophil‐to‐lymphocyte ratio (NLR), monocyte‐to‐lymphocyte ratio (MLR), platelet‐to‐lymphocyte ratio (PLR), and prognostic nutritional index (PNI), are useful prognostic factors in several malignant tumors. The present study explored the prognostic value of the NLR, MLR, PLR, and PNI in thymic epithelial tumor (TET) patients who underwent complete resection.

Methods

A total of 158 TET patients who underwent complete resection were involved in the analysis. Their NLR, MLR, PLR, and PNI values were obtained from a blood examination within one month before the initiation of treatment. A receiver operating characteristic curve analysis was conducted to determine the optimal cutoff values.

Results

The enrolled patients were stratified by cutoffs of 4.35 for the NLR, 0.22 for the MLR, 130.18 for the PLR, and 44.02 for the PNI. A univariate analysis revealed that high‐grade malignant TET, including type B2 and B3 thymoma, thymic carcinoma, and thymic neuroendocrine tumor; an advanced Masaoka stage; a high NLR; a high MLR; and a low PNI were significant predictors of a poor disease‐free survival (DFS). A multivariate analysis confirmed that an advanced Masaoka stage (HR = 5.5557, p = 0.0007) and a high MLR (HR = 3.3371, p = 0.0264) were independent predictors of a poor DFS.

Conclusions

Our study demonstrated that the pretreatment MLR was an independent predictor of the DFS in patients with TETs who underwent complete resection.

A large intrathoracic goiter with tracheal stenosis: Complete resection using a robot-assisted thoracoscopic approach

Growing intrathoracic goiters may compress surrounding organs and deteriorate the cardiopulmonary function. Treating such cases requires carefully considering how to maintain oxygenation and resect the tumor with minimal invasiveness without complications. We herein report a surgically resected case of a large intrathoracic goiter‐compressed trachea extending from the right lower pole of the thyroid gland to the carina. We secured the airway by intubation preparing for extracorporeal membrane oxygenation and successfully performed surgical complete resection using a robot‐assisted thoracoscopic and cervical approach. Intrathoracic goiter is a tumor with abundant neovascularity, and the right vagus nerve is displaced in the thoracic cavity, but a robot‐assisted thoracoscopic approach using CO₂ insufflation improved visualization at the narrow apex area of the thoracic cavity. Robot‐assisted thoracoscopic surgery is a useful surgical procedure enabling safe and minimally invasive surgery without recurrent laryngeal nerve palsy or tracheal injury for intrathoracic giant goiters extending into the thoracic cavity.

Comparison of the efficacy of novel two covering methods for spontaneous pneumothorax: a multi-institutional study

OBJECTIVES

The postoperative recurrence rate after thoracoscopic bullectomy for primary spontaneous pneumothorax (PSP) is not satisfactory. This retrospective study was conducted to elucidate an effective technique for improving the postoperative recurrence rate.

METHODS

The present study included 373 patients who underwent thoracoscopic bullectomy for PSP at three hospitals from January 2013 to May 2020. We compared the recurrence rate according to two methods that were used to cover the staple line after thoracoscopic bullectomy. Group A (146 patients) was treated with an absorbable polyglycolic acid (PGA) sheet plus fibrin glue and oxidised regenerated cellulose (ORC). Group B (227 patients) was treated with ORC alone.

RESULTS

There was no significant difference in preoperative characteristics of the patients. The postoperative recurrence rate of pneumothorax was 3.4% (5/146) in Group A and 17.2% (39/227) in Group B, respectively. Among 23 patients (Group A, n=3 and Group B, n=20) who received reoperation for recurrent pneumothorax, the site of recurrence was around the stapler line of the first operation in 1 of 5 (20%) patients in Group A and 28 of 39 (71.8%) patients in Group B. The 1-year recurrence-free rate was 97.4% (median follow-up period, 73 days (range, 2-3952 days)) in Group A and 80.9% (median follow-up period, 71 days (range 2-2648 days)) in Group B.

CONCLUSIONS

Coverage with a PGA sheet may prevent the postoperative recurrence of PSP. A large-scale prospective randomised study should be conducted to clarify the most effective treatment for PSP.

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).

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.

Examination on the necessity of pericardial fat tissue resection in extended thymectomy for myasthenia gravis

Background

Extended thymectomy with pericardial fat tissue resection has been a mainstay in the treatment for myasthenia gravies (MG), but few studies have examined the necessity of the pericardial fat tissue resection in extended thymectomy.

Methods

We pathologically examined the distribution of germinal centers in the resected thymus including the thymus-surrounding fat tissue. Patients who underwent extended thymectomy using subxiphoid thoracoscopy for generalized MG or thymoma with anti-acetylcholine receptor antibody (anti-AchR Ab) positivity from March 2015 to January 2021 were included in this study.

Results

A total of 20 patients underwent extended thymectomy (generalized nonthymomatous MG, n=5; generalized MG with thymoma, n=6; thymoma with anti-AchR Ab positivity, n=9). The resected specimens were divided to 6 parts and were pathologically examined to investigate the distribution of the geminal centers in all lesions. The number and distribution of germinal centers in the thymus varied depending on the patient, and no germinal centers were identified in the right or left pericardial fat tissues.

Conclusions

It is necessary to resect the pericardial fat tissue in patients whose preoperative images show the presence of pericardial fat tissue hyperplasia or ectopic thymoma. However, extensive pericardial fat tissue resection might not be necessary for all MG patients who undergo extended thymectomy with opening of the bilateral pleural by video-assisted or robot-assisted thoracoscopic surgery (RATS) via a subxiphoid approach.

Different patterns of pneumothorax in patients with soft tissue tumors treated with pazopanib: A case series analysis

To investigate pneumothorax patterns in pazopanib treatment by focusing on the positional relationship between the visceral pleura and metastatic lung tumor, we examined 20 patients with advanced soft tissue tumors who developed lung metastases and underwent pazopanib treatment between 2012 and 2019. Pneumothorax was classified into two types based on the location of the metastatic lesion around the visceral pleural area before pazopanib treatment: subpleural type, within 5 mm from the pleura; and central type, >5 mm from the pleura. We investigated the rates of pneumothorax and the associated risk factors. Five patients experienced pneumothorax (three subpleural and two central types). Cavitation preceded pneumothorax in 83% of patients and led to connection of the cavitated cyst of the metastatic lesion to the chest cavity in the shorter term in patients with the subpleural type. Conversely, a more gradual increase in the cavity size and sudden cyst rupture were observed in the central type. The risk factors for pneumothorax were cavitation after initiating pazopanib and intervention before pazopanib, either ablation or surgery. The location of the metastatic lesions was not a risk factor for the occurrence of pneumothorax. In conclusion, pneumothorax is an adverse event associated with pazopanib treatment. Therefore, attention must be paid to predisposing factors such as the formation of cavitation after pazopanib initiation and previous interventions to the lungs. Moreover, because subpleural pneumothorax tends to occur earlier than the central type, a different time course can be anticipated based on the positional relationships of the metastatic lesions to the visceral pleura.

Type A thymoma with simultaneous solitary intrapulmonary metastasis: A case report

A 79‐year‐old woman was referred to our facility because of an abnormal chest shadow. Chest computed tomography (CT) showed a solitary right middle lung nodule with a maximum diameter of 3 mm and anterior mediastinal nodule with a maximum diameter of 21 mm. The lung nodule was suspected of being a primary lung cancer rather than a metastatic tumor because there were no primary malignant tumors, apart from an anterior mediastinal tumor visible on diagnostic imaging, including F¹⁸ fluorodeoxyglucose‐positron emission tomography, and a solitary lung nodule. Partial lung resection by video‐assisted thoracoscopic surgery (VATS) was performed, and the intraoperative frozen section of the tumor tissue resulted in a diagnosis of carcinoid tumor. As a result, right middle lobectomy by VATS was performed. The final histological diagnosis of the permanent specimen was intrapulmonary type A thymoma. VATS thymectomy was performed three months later. The histological diagnosis was type A thymoma with intrapulmonary metastasis (Masaoka stage IVb). Additional therapy was not performed because complete resection was achieved. Follow‐up CT was performed once every six months after the operation. The patient has been followed up for one year without any further recurrence.

The usefulness of fluorodeoxyglucose-positron emission tomography as a preoperative diagnostic tool for thymic epithelial tumors

Background

To investigate the usefulness of ¹⁸F-fluorodeoxy glucose-positron emission tomography (¹⁸F-FDG PET) for the preoperative imaging diagnosis of malignant grade in thymic epithelial tumors (TETs) and the correlation between the maximum standardized uptake value (SUVmax) and tumor size in TETs.

Methods

We retrospectively investigated 51 patients with TETs performed ¹⁸F-FDG PET. The SUVmax was compared between thymic carcinomas and thymomas. We also evaluated the difference in the SUVmax limited to small TETs. In addition, the correlation between the SUVmax and the tumor size was evaluated.

Results

The mean SUVmax of thymic carcinomas (n=12) and thymomas (n=39) was 5.71±2.6 and 3.08±1.4, respectively. The SUVmax of thymic carcinomas was significantly higher than that of thymomas (P<0.001). The mean SUVmax of these small thymic carcinomas (n=3) and thymomas (n=13) was 2.97±0.24 and 1.79±0.47, respectively. The SUVmax of the small thymic carcinomas was significantly higher than that of the thymomas (P=0.001). We found a positive correlation between the SUVmax and the maximum tumor size of TETs (correlation coefficient: 0.632, P<0.001).

Conclusions

¹⁸F-FDG PET might be useful for evaluating the preoperative malignancy of TETs. Of note, the maximum tumor size should be considered when performing assessments by ¹⁸F-FDG PET.

Pericardial immunoglobulin G4-related inflammatory pseudotumor after right upper lobectomy for lung cancer

A 75‐year‐old woman underwent thoracoscopic right upper lobectomy for lung cancer. A histopathological examination showed adenocarcinoma, pT1aN0M0 stage IA1. At six months after surgery, chest computed tomography (CT) revealed pericardial nodules that had not been detected before pulmonary resection. Postoperative CT performed two months later revealed that the nodules were growing and F¹⁸ fluorodeoxyglucose‐positron emission tomography showed a maximum standardized uptake of 9.87. Blood tests revealed no elevated tumor markers, with the exception of a mildly elevated interleukin‐2. Based on the above results, thoracoscopic biopsy was performed due to the suspected recurrence of lung cancer or malignant lymphoma. The histopathological examination of the nodule revealed immunoglobulin G4 (IgG4)‐related inflammatory pseudotumor. The serum IgG4 levels were elevated (358 mg/dL, normal: 4.5–117.0 mg/dL). No additional treatment was required because all nodules were observed to have disappeared naturally on a follow‐up CT scan performed two months after the surgical biopsy. The patient has been followed‐up for two years without recurrence.

Key points

Significant findings of the study

We report a case of pericardial immunoglobulin G4‐related inflammatory pseudotumor that appeared after right upper lobectomy for lung cancer, and which naturally disappeared without any treatment.

What this study adds

There was an immunoglobulin G4‐related inflammatory pseudotumor which appeared as multiple nodules in the pericardial space, and this should be kept in mind when considering the differential diagnosis of intrapericardial nodules.

Long-term survivor of pulmonary combined large cell neuroendocrine carcinoma treated with nivolumab

Several authors have previously reported that patients with pulmonary combined large cell neuroendocrine cancer ( LCNEC) have a poor prognosis and there is no consensus on the treatment strategy for combined LCNEC as well as LCNEC. Here, we report the case of a long‐term survivor with pulmonary combined LCNEC. The patient was a 60‐year‐old man who underwent thoracoscopic right lower lobectomy. The final histopathology and staging of the tumor showed LCNEC combined with squamous cell carcinoma and T2aN0M0 stage IB. Multimodality treatments including chemotherapy, radiotherapy and surgery for several recurrences were performed after the pulmonary surgery. After immune checkpoint inhibitor (ICI) therapy with nivolumab, all the metastatic lesions shrunk and a partial response was maintained at five years after the first surgery. In our case, ICI after multimodality therapy combining cytotoxic anticancer drugs and radiotherapy was effective in LCNEC with metachronous multiple metastases.

Key points

Significant findings of the study

Immune checkpoint inhibitor after multimodality therapy combining cytotoxic anticancer drugs and radiotherapy was effective in LCNEC with metachronous multiple metastases. The patient survived over five‐years after the first surgery.

What this study adds

Immune checkpoint inhibitor may be effective in some LCNEC patients.

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.

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.

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.

The relationship between the expression of thymidylate synthase, dihydropyrimidine dehydrogenase, orotate phosphoribosyltransferase, excision repair cross-complementation group 1 and class III β-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 β-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.

S-1 vs. paclitaxel plus carboplatin as adjuvant chemotherapy for completely resected stage II/IIIA non-small-cell lung cancer

The majority of patients with completely resected stage II or IIIA non-small-cell lung cancer (NSCLC) require adjuvant chemotherapy to improve survival following surgery. In the present trial, the 2-year disease-free survival (DFS), and the feasibility and safety of S-1 as an adjuvant chemotherapy for advanced lung cancer were evaluated. A total of 40 patients with completely resected stage II or IIIA NSCLC were enrolled and randomized to receive postoperative chemotherapy with either up to 4 cycles of paclitaxel plus carboplatin (arm A) or with up to 1 year of S-1 (arm B). The primary endpoint was 2-year DFS. The secondary endpoints were feasibility and toxicity. A total of 40 patients were enrolled, but 3 were excluded in accordance with the exclusion criteria. The remaining 37 patients were analyzed. The 2-year DFS rate was 54.2% in arm A and 84.2% in arm B. Overall, 15/18 (83.3%) patients completed 4 cycles of paclitaxel plus carboplatin and 13/19 (68.4%) completed 1-year of S-1adjuvant chemotherapy. Of the 18 (16.7%) patients in arm A, 3 experienced grade 3 or 4 adverse events, while none in arm B experienced such events. Therefore, S-1 chemotherapy for patients with completely resected stage II or IIIA NSCLC was a feasible and safe regimen, and it may therefore be considered as a potential adjuvant chemotherapy option for advanced NSCLC.

The detectability of the pretreatment EGFR T790M mutations in lung adenocarcinoma using CAST-PCR and digital PCR

BACKGROUND

A gatekeeper T790M mutation is thought to cause resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment. The detection of a 2nd mutation is important for planning the next therapy when patients acquire resistance to the first line EGFR-TKI.

METHODS

We used a competitive allele-specific polymerase chain reaction (CAST-PCR) to analyze the incidence and clinical significance of T790M mutations in 153 lung adenocarcinomas with EGFR-activating mutations. To increase the sensitivity and specificity of the detection of T790M mutations, we subjected 20 of the 153 cases to a digital PCR. The genomic DNAs were extracted from frozen, surgically resected tumor tissue specimens.

RESULTS

The CAST-PCR detected T790M mutations in 45 (29.4%) of the 153 cases. The analytical sensitivity in the detection T790M mutations was 0.13-2.65% (average 0.27%, median 0.20%). In contrast, the digital PCR, detected T790M mutations in 8 (40%) out of 20 cases.

CONCLUSIONS

Our study shows that the pretreatment incidence of T790M mutation was less than that reported in previous studies. In order to clinically use pretreatment EGFR T790M mutation identification method, we should clarify the adequate methods and tissue preserved status.

Expression of excision repair cross-complementation group 1 and class III β-tubulin in thymic carcinoma

Thymic carcinoma is a rare mediastinum malignant tumor derived from thymic epithelial cells. With the exception of complete resection, an effective therapy has not been established to date for advanced or relapsed thymic carcinoma. The present study examined the protein expression of excision repair cross-complementation group 1 (ERCC1) and class III β-tubulin (TUBB3), which are consider to be indicators of the anticancer activity of platinum-based and taxane-based chemotherapy, respectively. The expression of ERCC1 and TUBB3 proteins was examined in 40 thymic carcinoma patients who underwent either surgical resection or core-needle biopsy. The present study investigated whether the expression of ERCC1 and TUBB3 proteins was associated with the overall survival and clinicopathological factors of thymic carcinoma patients. The expression of ERCC1 and TUBB3 proteins was also evaluated in 50 patients who underwent curative resection for non-small cell lung cancer (NSCLC). The expression of ERCC1 and TUBB3 proteins was positive in 8 cases (20%) among the thymic carcinoma patients. ERCC1 was expressed in 21 cases (42%), while TUBB3 was expressed in 27 cases (54%), among the 50 NSCLC patients evaluated in the present study. Only complete resection was observed to be associated with a better prognosis than incomplete resection (P=0.0341). Other clinicopathological factors, including expression of ERCC1 and TUBB3 proteins, exhibited no effect on overall survival. The expression of ERCC1 and TUBB3 proteins in the thymic carcinoma cases was lower than that in the NSCLC cases. The present results suggest a possibility for better antitumor effects of platinum-based and taxane-based chemotherapy on thymic carcinoma patients.

A case of mediastinum undifferentiated high grade pleomorphic sarcoma

Primary anterior mediastinum undifferentiated high grade pleomorphic sarcoma is rare that most physician including thoracic surgeon would not experience this disease. Huge anterior mediastinum tumor pressed the heart and it invaded into the left pulmonary arterial trunk. We did the mediastinum tumor resection, left pneumonectomy and left phrenic, sympathetic and vagus nerve merger excision. But the recurrence lesions were detected in the right lung, the left thoracic cavity and thoracic vertebrae within one month after operation. We reported a case of aggressively progressed undifferentiated high grade pleomorphic sarcoma originated from the anterior mediastinum.

Intra-tumor heterogeneity of BRAF V600E mutation in lung adenocarcinomas

BRAF mutations exist in numerous types of cancer, including melanomas, colorectal cancers and lung cancers. The V600E-specific inhibitor vemurafenib has marked clinical activity in patients with BRAF V600E-mutated melanoma. However, there are many cases of resistance to vemurafenib. This may be due to the reported intra-tumor heterogeneity of the BRAF V600E mutation in primary melanomas. BRAF mutations are found in 1-5% of non-small cell carcinomas (NSCLCs), almost exclusively in adenocarcinoma. A few cases have been reported in which vemurafenib was effective against BRAF V600E-mutated lung cancers. In a previous study, five lung adenocarcinomas with BRAF V600E mutation were detected by direct sequencing. The present study analyzed these tumors for the percentage of mutation (%mutation) by competitive allele-specific polymerase chain reaction (CAST-PCR) assay. In addition, sections of all components of the adenocarcinomas were obtained by laser microdissection and analyzed. The %mutations of BRAF V600E within the macrodissected tumors (cases 1-5) were: Case 1, 10.0%; case 2, 8.0%; case 3, 8.9%; case 4, 21.5%; and case 5, 14.9%. In four cases (cases 2-5), the %mutations of each adenocarcinoma component were as follows: Case 2, lepidic growth 6.5-24.5%, papillary 1.3-11.2% and acinar 9.8%; case 3, solid 2.5-69.9%, acinar 12.4-27.1% and papillary 3.7-17.4%; case 4, acinar 10.0-45.0% and papillary 44.0%; and case 5, papillary 3.7-93.4%. Sensitive BRAF mutation detection methods were used and evidence for heterogeneity of the BRAF V600E mutation in these lung adenocarcinoma cases was observed. Targeted therapy with a BRAF V600E inhibitor such as vemurafenib may have potential in the treatment of lung cancer with this mutation; however, it is necessary to consider how the treatment effect of and drug resistance to BRAF V600E inhibitors are affected by the presence of heterogeneity in future studies.

Increased BRAF copy number in lung adenocarcinoma

Point mutation of the BRAF gene is a genetic event that occurs in a subset of lung adenocarcinoma cases. For example, BRAF V600E is a driver mutation that can be effectively targeted using selective BRAF and/or MEK inhibitors. The present study hypothesized that an increase in BRAF copy number may be correlated with certain clinicopathological features of lung adenocarcinoma in Japanese patients. The BRAF gene copy number was analyzed using quantitative polymerase chain reaction amplifications in 29 surgically treated lung adenocarcinoma cases without EGFR or Kras mutations from Nagoya City University Hospital (Nagoya, Japan). Seven BRAF-mutant cases were included. Increased BRAF gene copy number was identified in three lung adenocarcinoma patients (10.3%), all of which exhibited the V600E mutation. Using fluorescence in situ hybridization with BRAF-specific and chromosome 7 centromeric probes, increased copy number status was associated with gene amplification or gain of chromosome 7. Although increased BRAF copy number was correlated with BRAF V600E mutations, numerical changes in BRAF copy number were rare and mild in lung adenocarcinoma, resulting in no significant difference in pathological tumor status or tumor stage.

Genetic epidemiology of tooth agenesis in Japan: a population- and family-based study

Tooth agenesis is one of the most common congenital anomalies in humans. However, the etiology of tooth agenesis remains largely unclear, as well as evidence base useful for genetic counseling. Therefore, we estimated the prevalence and sibling recurrence risk, and investigated agenetic patterns systematically. Tooth agenesis was classified into two subtypes: hypodontia (one to five missing teeth) and oligodontia (six or more missing teeth). The prevalence of these two subtypes were 6.8% [95% confidence interval (CI): 6.1-7.7%] and 0.1% (95% CI: 0.04-0.3%), respectively, and sibling recurrence risk of these were 24.5% (95% CI: 13.8-38.3%) and 43.8% (95% CI: 26.4-62.3%), respectively. This result suggests that the severe phenotype, oligodontia, might be mostly transmitted in a dominant fashion. Using a simple statistical modeling approach, our data were found to be consistent with a bilateral symmetry model, meaning that there was equal probability of missing teeth from the right and left sides.

Investigation of neurotrophic tyrosine kinase receptor 1 fusions and neurotrophic tyrosine kinase receptor family expression in non-small-cell lung cancer and sensitivity to AZD7451 in vitro

Advances in the molecular segmentation of lung cancer has raised the possibility that neurotrophic tyrosine kinase receptor (NTRK) 1 fusions and NTRK1-3 expression may be promising molecular targets for future therapeutic interventions. We investigated the antitumor effects of a selective pan-NTRK inhibitor, AZD7451, by evaluating its antiproliferative effects on the KM12 cell line (a colorectal cancer cell line harboring a tropomyosin-NTRK1 fusion) and the H460 and H810 cell lines [large-cell neuroendocrine carcinoma (LCNEC) cell lines expressing NTRK2]. Relative quantitative polymerase chain reaction (qPCR) was performed to measure the mRNA levels of the NTRK1-3 tyrosine kinase domain using cDNA extracted from KM12, H460 and H810 cells. The cultures were grown in 6-well plates at a density of 1.0×10⁶ cell/well and treated with AZD7451 at different doses (1, 2.5, 4, 5, 7.5 and 10 nM) using dimethyl sulfoxide as a control. Following a 24-h incubation, the number of surviving cells was measured using a hemocytometer. Furthermore, we performed western blotting of the high-affinity nerve growth factor receptor (TRKA) and NTRK2 (TRKB) proteins and monitored the effects on the downstream signaling pathways Akt and ERK in these cell lines following treatment with AZD7451 (KM12 and H460: 0, 1 and 5 nM; H810: 0 and 5 nM). Immunohistochemical analyses of the surgically resected samples were also performed, using anti-NTRK1,2 antibodies. We performed reverse-transcription PCR and direct sequencing to investigate NTRK fusions in 268 patients; however, were unable to confirm the presence of NTRK fusions in this cohort. Further immunohistochemical analyses of the primary patient samples demonstrated that none of 61 tumors had NTRK1 overexpression and 7 of 39 samples exhibited NTRK2 expression, including 1 LCNEC sample. The qPCR results from the KM12 cell line revealed an apparent increase and overexpression of NTRK1 mRNA levels, while H460 cells exhibited a modest increase and the H810 cell line showed no apparent increase in the expression of any NTRK1-3 isoforms. There were no increases in the NTRK2 mRNA levels in any of the three cell lines, although KM12 and H460 cells exhibited low levels of NTRK2 expression. In vitro growth and proliferation of the KM12 cell line harboring the NTRK1-fusion was found to be potently inhibited by AZD7451 at a concentration of 2 nM. The proliferation of H460 cells was also found to be inhibited at a concentration of 5 nM, while there was no apparent inhibitory effect of AZD7451 on the growth or proliferation of H810 cells. Western blotting of KM12 cells treated with AZD7451 also revealed a potent inhibition of TRKA phosphorylation following AZD7451 treatment. Analysis of H460 cells confirmed the expression and inhibition of phosphorylation of NTRK2, whereas there was little to no expression of TRKA/B in H810 cells. Subsequent in vitro analysis of cell lines treated with the pan-TRK inhibitor AZD7451 suggested that the proliferation of KM12 and H460 cells was significantly inhibited by AZD7451, while H810 cells expressing low levels of wild-type NTRK1-3 were not inhibited. Based on these results, there is potential for a NTRK-dependent proliferation driver in a subpopulation of lung cancer patients with NTRK expression. In addition, pharmacological inhibition with a NTRK inhibitor, such as AZD7451, in cells harboring NTRK1 fusions, may be associated with beneficial antitumor effects.

APOBEC3B gene overexpression in non-small-cell lung cancer

Recent study results have demonstrated that a subclass of apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) cytidine deaminase may induce mutation clusters in various types of cancer. From the Cancer Genome Altas, an APOBEC mutation pattern was identified in bladder, cervical, breast, head and neck and lung cancers. In the present study, APOBEC3B mRNA expression was investigated using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay using LightCycler in surgically treated non-small-cell lung cancer (NSCLC) cases. Additionally, 88 surgically removed Japanese NSCLC cases were analyzed for mRNA level. The results showed that APOBEC3B/β-actin mRNA levels were significantly higher in lung cancer (1,598.481±6,465.781) when compared to adjacent normal lung tissues (2,116.639±8,337.331, P=0.5453). The tumor/normal (T/N) ratio of APOBEC3B/β-actin mRNA levels was not different within the gender, age, smoking status and pathological stages. The T/N ratio of APOBEC3B/β-actin mRNA levels was not significantly different in epidermal growth factor receptor (EGFR) or Kras mutation-positive cases as compared to the wild-type cases.

Prognosis of recurrent non-small cell lung cancer following complete resection

Prognosis following recurrence subsequent to complete resection of non-small-cell lung cancer (NSCLC) is considered a multifactorial process dependent on clinicopathological, biological and treatment characteristics. Gefitinib was approved for lung cancer treatment in Japan in 2002. The aim of the current study was to quantify the prognostic effects of these characteristics on post-recurrence prognosis. In total, 127 NSCLC patients were analyzed who underwent complete resection and subsequently had recurrent cancer. The correlation between characteristics of the initial and recurrent disease with post-recurrence prognosis was investigated. The factors clearly associated with post-recurrence prognosis using Cox proportional hazards models were age at recurrence (those <65 years of age typically had better prognoses) and interval between initial resection and recurrence (intervals of <1 year accompanied a worse prognosis). Epidermal growth factor receptor (EGFR) mutant patients treated with EGFR tyrosine kinase inhibitors (TKIs), exhibited the longest median survival following recurrence (37.4 months) in the sample. Treatment, particularly EGFR TKIs for recurrent NSCLC, was observed to significantly prolong survival. The results of the study highlight that various treatment modalities according to the clinical background of the patient should be considered in patients with postoperative recurrent NSCLC.

[Video-assisted thoracoscopic extended thymectomy while using the carbon dioxide insufflation]

A 40-year-old woman with generalized myasthenia gravis was scheduled for extended thymectomy. The patient under general anesthesia with double-lumen intubation was placed in the supine position. A sealed 5 mm trocar and 2 sealed 12 mm trocars were inserted through the 3rd, 4th and 5th intercostal space at the both side of the anterior axillary line. Under carbon dioxide insufflations by positive pressure of 7 mmHg, thymus and fat tissue was resected completely. An operation time was 162 minutes, and blood losses during operation were 5 ml. The present method was thought to be safe and useful for conducting extended thymectomy.

[A case of double cancer of sigmoid colon cancer with lung metastases, peritoneal dissemination and early gastric cancer responding to S-1]

A 73-year-old man was referred to our hospital with complaints of constipation and defecation caused by a sigmoid colon tumor. After examination, he was diagnosed as sigmoid colon cancer with lung metastasis, peritoneal dissemination and early gastric cancer. To prevent bowel obstruction, a sigmoid colon resection was performed. On postoperative day 20, S-1 (100 mg/body for 4 weeks followed by 2 drug-free weeks) treatment was started. After 13 courses of treatment, gastrointestinal fiberscope revealed that the gastric cancer was remarkably reduced, and after 16 courses, computed tomography revealed that the lung metastasis was remarkably reduced. Although after 12 courses, elevation of bilirubin, the treatment could be possible to continued on a lowered dose of S-1 from 100 mg to 80 mg/body. Twenty-four months after the operation, good control of cancer has been maintained, and the treatment is continuing. S-1 treatment was proved effective for double cancer of the advanced colorectal cancer and the gastric cancer.

Possible involvement of nitric oxide in carbachol-induced activation of transglutaminase in rat superior cervical sympathetic ganglia

The addition of a muscarinic agonist, carbachol (Carb, 0.1 mM), to a physiological medium markedly increased Ca(2+)-dependent transglutaminase (TG) activity (approximately 10-fold) in isolated rat superior cervical sympathetic ganglia (SCG) following in vitro aerobic incubation for 30 min at 37 degrees C. The Carb-evoked stimulation of ganglionic TG activity was considerably reduced (-51%) in the presence of NG-monomethyl-L-arginine (L-NMMA, 50 microM), a selective inhibitor of nitric oxide (NO) synthase. While the suppressant effect of L-NMMA was completely eliminated by the addition of an excess concentration of L-arginine (0.5 mM), a precursor of NO. These observations imply that Carb-induced TG activation possibly involves NO mediation in SCG tissue. The Carb-induced elevation in ganglionic TG activity was markedly reduced (-84%) at as early as 15 min of incubation in the medium containing hemoglobin (Hb) (20 microM), an agent that scavenges only extracellular NO gas. Thus, it is evident that a large fraction of NO released from inside the neuronal cells to extracellular space could rapidly diffuse back into the same group of cells to induce activation of the tissue TG. Methylene blue (MB), an inhibitor of soluble guanylate cyclase (GC), at 0.5 mM, a concentration which is effective in almost abolishing the Carb-evoked synthesis of cyclic GMP (cGMP), had no effect on ganglionic TG activation induced by Carb. Therefore, an increase in cGMP synthesis mediated by NO might not participate in NO-dependent ganglionic TG activation following the stimulation with Carb.(ABSTRACT TRUNCATED AT 250 WORDS)

The intercellular communication via nitric oxide and its regulation in coupling of cyclic GMP synthesis upon stimulation of muscarinic cholinergic receptors in rat superior cervical sympathetic ganglia

Cyclic GMP (cGMP) production in rat superior cervical sympathetic ganglia (SCG) was markedly increased (ca. 7-9-fold) by the addition of either acetylcholine (ACh; 0.1 mM) or a muscarinic agonist, carbachol (Carb; 0.1 mM), in the presence of an inhibitor (3-isobutyl-1-methylxanthine) for cGMP hydrolytic enzyme during in vitro aerobic incubation at 37 degrees C for 5 min. The ACh-induced accumulation of cGMP in SCG was effectively blocked (-73%) by the further addition of atropine (10 microM), a muscarinic antagonist, whereas a nicotinic blocker, hexamethonium (10 microM) partially antagonized (-41%) this ACh stimulation. The inhibitory effect of hexamethonium on ACh-evoked ganglionic cGMP production was effectively augmented (-83%) by addition of NG-monomethyl-L-arginine (L-NMMA, 50 microM), a compound that inhibits nitric oxide (NO) synthesis from L-arginine. Comparable inhibition of cGMP formation was observed following application of L-NMMA to the SCG upon stimulation of Carb. In contrast, L-NMMA had no effect on the decreased level of ACh-evoked cGMP production caused by the muscarinic antagonist. The Carb-induced elevation of ganglionic cGMP synthesis was significantly reduced within 1 min of incubation in the medium containing hemoglobin (Hb; 20 microM), an agent that scavenges only the extracellular fraction of NO. Thereafter, the tissue cGMP formation attenuated to the control level by subsequent incubation for several minutes. Addition of protein kinase C (PKC) activator, 12-O-tetradecanoylphorbol 13-acetate (TPA; 1 microM) to the medium significantly decreased Carb-evoked cGMP synthesis (-61%) in SCG, whereas superoxide dismutase (SOD; 30 U/ml) only slightly suppressed the Carb stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Blockade effect of nerve growth factor on GM1 ganglioside-induced activation of transglutaminase in superior cervical sympathetic ganglia excised from adult rat

The activity of transglutaminase (TG), a Ca(2+)-dependent enzyme indicating tissue degradation or differentiation, showed in isolated adult rat superior cervical ganglia (SCG) a rapid (within 15 to 30 min) and marked (approx. 5- to 8-fold) increase with the addition of either GM1 ganglioside (GM1, 5 nM), which is rich in synapses, or sialyl cholesterol (SC, 20 microM), a synthetic sialic acid-containing compound, to the incubation medium at 37 degrees C. Under the same incubation conditions, addition of GM1 or SC decreased protein kinase C (PKC) activity (-26% to -39%) in the cytosolic fraction of the SCG, but increased the enzymic activity (+39% to +61%) in the particulate (cell membrane) fraction, suggesting that a sialic acid-containing compound (GM1 or SC) promotes PKC translocation from the cytosol to the membrane in ganglionic neurons. By contrast, addition of a promoting factor for survival of sympathetic neurons even in adulthood, nerve growth factor, (NGF, 0.25 micrograms/ml) to the medium significantly decreased ganglionic TG activity (-43%). This inhibition was completely antagonized by the co-addition of NGF-monoclonal antibody (0.75 microgram/ml). An effective blockade of GM1- or SC-induced stimulation of ganglionic TG activity was seen by further addition of NGF to the medium. Also, NGF almost abolished the translocation of ganglionic PKC activity induced by the sialic acid-containing compounds, although either NGF or 12-O-tetradecanoylphorbol ester (TPA) alone stimulated the cytosolic PKC activity (approx. +30%) in the tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of axotomy on nitric oxide-dependent cyclic GMP production of rat superior cervical sympathetic ganglia in response to norepinephrine

Cyclic GMP (cGMP) production in superior cervical sympathetic ganglia (SCG) isolated from rats was markedly enhanced (approx. 4.5-fold) by the addition of L-arginine (L-Arg, 100 microM) plus an inhibitor (3-isobutyl-1-methylxanthine) for cGMP hydrolytic enzyme during in vitro aerobic incubation at 37 degrees C for 10 min. This accelerated accumulation of ganglionic cGMP was effectively reversed by approximately 50% when NG-monomethyl-L-arginine (L-NMMA, 50 microM), a compound that inhibits nitric oxide (NO) synthesis from L-Arg, was further added to the medium. These observations imply that cGMP production with possible involvement of a mechanism depending on NO synthesis may be functionally operating in the ganglionic tissue. Application of norepinephrine (NE, 50 microM) with pargyline, a monoamine oxidase inhibitor, to the medium also elevated the ganglionic cGMP level at a magnitude comparable to that shown by L-Arg addition, while co-addition of L-NMMA largely (approx. -60%) eliminated the NE-induced increase in ganglionic cGMP formation. In axotomized SCG one week prior to examination, where sympathetic neurons were degenerated and reactive proliferation of glial cells was in progress, augmented stimulatory effect (more than 8-fold) of NE on cGMP production was seen compared to that caused in unoperated ganglia or in SCG 1 week following denervation, where preganglionic cholinergic nerve terminals were destroyed. When axotomized SCG were transferred to in vitro incubation conditions, addition of an alpha-1 adrenergic antagonist, prazosin (1 microM) to the medium virtually reduced the accelerative effect of NE to less than 25% of the NE-induced cGMP level in the tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid and transient alterations in transglutaminase activity in rat superior cervical ganglia following denervation or axotomy

The activity of transglutaminase (TG), a Ca(2+)-dependent enzyme contributing to cross-linkage formation of intracellular polypeptide chains decreased rapidly to ca. 25% of control level in superior cervical ganglia (SCG) within 0.5 h following denervation. The reduced level was maintained for at least 24 h. By contrast, following axotomy, ganglionic TG activity increased by ca. 50% within 1 h, maintained the increase to 4 h, and returned to control level by 24 h. When SCG were transferred to aerobic in vitro incubation conditions 3 h following denervation, the addition of the protein kinase C (PKC) inhibitor, trifluoperazine (TFP, 10 micrograms/ml), to the medium partially reversed the denervation-induced reduction in ganglionic TG activity. Addition of a PKC activator, 12-O-tetradecanoylphorbol 13-acetate (TPA, 1 microM), had no effect on the TG activity. These findings suggest that the pathway resulting in the rapid, denervation-induced inhibition of TG activity may involve the transsynaptic activation of PKC. When SCG were placed in vitro 3 h following axotomy, addition of nerve growth factor (NGF, 0.25 micrograms/ml) to the medium reversed approximately one-half of the axotomy-induced increase in TG activity. Thus, following axotomy, the reduction in delivery to the SCG of NGF, which can be transported retrogradely within the axon and is indispensable for morphological and functional survival of sympathetic neurons, may trigger the transient, axotomy-induced TG activation in the SCG.

Selective alterations in transglutaminase activity of rat superior cervical ganglia in response to neurotransmitters, high potassium and sialic acid-containing compounds

We examined the in vitro effects of neurotransmitters, high KCl as well as sialic acid-containing compounds (GM1; SC) on transglutaminase (TG) activity in isolated superior cervical ganglia (SCG) one week after denervation or axotomy. Following denervation, TG activity in SCG decreased to 83% of the unoperated control value, whereas that of axotomized ganglia was 28% of control. Thus, TG activity was relatively unaffected when sympathetic ganglionic neurons were preserved, but was markedly reduced under conditions where neurons were degenerating. Addition of ACh (0.1 mM) to the medium during aerobic incubation stimulated TG activity more than 3-fold in denervated ganglia but had no effect on TG activity in axotomized ganglia. Similarly, the NE (0.05 mM)-induced decrease of TG activity observed in intact SCG was also seen following denervation (-49%) but not following axotomy. In denervated SCG, the stimulatory effects of ACh were virtually abolished by co-addition of the cholinergic antagonists, atropine or hexamethonium, while the suppressant effects of NE were blocked by the adrenergic antagonists, propranolol, prazosin or yohimbine. These results imply that transmitter-induced rapid changes in TG activity occur predominantly in ganglionic neurons. When the ganglia were depolarized by high KCl (50 mM), a significant increase in TG activity in each intact, denervated and axotomized SCG was seen with qualitatively similar manner, suggesting that high KCl-induced depolarization affects both neuronal and glial components in the SCG. The marked increase in ganglionic TG activity in response to GM1 (5 nM) and synthetic SC (0.02 mM) were lost in denervated SCG but only partially reduced in axotomized SCG.(ABSTRACT TRUNCATED AT 250 WORDS)