Clinicopathological Impacts of Expression of Neuronal Markers in Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a tuberous sclerosis complex (TSC)-associated tumor, characterized by the expression of neural crest lineages including neuronal markers. Neural crest cells can differentiate into multiple cell types that contribute to tissues associated with TSC-related tumors, and TSC-related tumors could be specifically associated with distinct neural crest subtypes. This study aimed to clarify the clinicopathological effects of expression of neuronal markers in LAM. Lung tissues from 40 patients with LAM (of whom 13, 1, and 26 had undergone lung transplantation, lobectomy, and partial lung resection, respectively) were immunohistochemically analyzed. All patients were women, and their median age was 36 years (range: 24-62 y). All patients who underwent lung transplantation or lobectomy were classified as LAM histologic score (LHS)-3, whereas those who underwent partial lung resection were classified as LHS-1. LAM cells expressed peripherin (65%), and neuron-specific βIII-tubulin (43%). A comparison of the early (LHS-1) and advanced (LHS-3) stages of LAM revealed that neuron-specific βIII-tubulin was significantly expressed in the early stage of LAM ( P = 0.0009). Neuron-specific βIII-tubulin-positive LAM was associated with younger age ( P < 0.0001), the coexistence of renal angiomyolipoma ( P = 0.027), and the absence of retroperitoneal LAM ( P = 0.045). Furthermore, based on the expression levels of immunohistochemical markers in LAM, 2 distinct clusters with different expression levels of neuronal markers were observed. Approximately 40% to 60% of patients with LAM expressed neuron-specific βIII-tubulin and peripherin. Neuronal expression may be associated with disease severity.

Postoperative hormonal therapies reduce the recurrence of thoracic endometriosis-related pneumothorax

OBJECTIVES

Thoracic endometriosis-related pneumothorax (TERP) frequently recurs even after surgery. Meanwhile, postoperative hormonal therapies (HTx) are believed to be effective for pelvic endometriosis. Therefore, we evaluated the relationship between postoperative TERP recurrence and postoperative HTx in a retrospective observational study.

METHODS

We retrospectively reviewed the data of patients with TERP who underwent the first video-assisted thoracoscopic surgery between January 2011 and February 2022.

RESULTS

Of the 248 patients eligible for this study, 67 (27.0%) experienced postoperative TERP recurrence. Postoperative HTx were administered to 70 patients (28.2%). Dienogest was the most frequently administered drug, given to 56.7% of patients. Following univariable analysis, postoperative hormonal therapies was closely related to reduce postoperative recurrence (P = 0.003). Likewise, the multivariable analysis revealed postoperative hormonal therapies were significantly associated with the risk reduction of recurrence (hazard ratio 0.28, P < 0.001).

CONCLUSIONS

Postoperative HTx reduced TERP recurrence. We hypothesize that HTx may control residual endometrial tissues to avoid TERP if pleural endometrial tissues are resected as much as possible.

Effect of common sedation agents on feline splenic size determined via ultrasonography

AIMS

To evaluate the effect of IM administration of three sedative drugs, acepromazine, alfaxalone and dexmedetomidine, in combination with morphine, on the size of the feline spleen using ultrasonography.

METHODS

Twenty-four client-owned cats undergoing elective de-sexing or minor procedures were recruited for a focused ultrasonographic examination of the spleen prior to and at 10, 20 and 30 minutes following administration of one of three randomly assigned IM sedation protocols: 0.05 mg/kg acepromazine (ACE group), 3 mg/kg alfaxalone (ALF group), or 10 μg/kg dexmedetomidine (DEX group), in combination with 0.5 mg/kg morphine. B-mode images of the spleen were collected and measured following a standardised protocol. Cardiorespiratory parameters and sedation score were also recorded. Mean thickness of the head, body and tail of the spleen for each group at 10, 20 and 30 minutes after drug administration was compared to baseline.

RESULTS

Mean splenic thickness increased over time in the ACE group (thickness of body at T0 = 8.9 (SE 2.1) mm and at T30 = 10.5 (SE 2.0) mm; p = 0.001) and the ALF group (thickness of body at T0 = 8.8 (SE 1.0) mm and at T30 = 10.3 (SE 1.7) mm; p = 0.022) but not in the DEX group (thickness of body at T0 = 8.6 mm (1.2) and at T30 = 8.9 mm (0.6); p = 0.67). Mean arterial blood pressure in the DEX group was significantly higher than in the other groups (p = 0.002). Sedation scores in the DEX group were consistently high for the entire period. However, the sedation score in the ACE group increased over 30 minutes (p = 0.007). Sedation score in the ALF group was highest at 10 minutes but gradually decreased over the following 20 minutes (p = 0.003).

CONCLUSIONS

Sedation with IM dexmedetomidine and morphine did not change splenic size, whereas acepromazine or alfaxalone and morphine increased it regardless of the degree of sedation.

CLINICAL RELEVANCE

Where splenomegaly is identified in a cat sedated with acepromazine or alfaxalone, the effects of the sedation protocol could be considered as a possible cause.

Clinical and genetic features of 334 Asian patients with Birt-Hogg-Dubé syndrome (BHDS) who presented with pulmonary cysts with or without a history of pneumothorax, with special reference to BHDS-associated pneumothorax

BACKGROUND

The clinical pulmonary manifestations and genetic features of Birt-Hogg-Dubé syndrome (BHDS) in Asian patients remained unclear. We aimed to clarify the clinical features of BHDS-associated pneumothorax (PTX) and retrospectively investigate potential contributing factors in the largest Asian cohort to date.

METHODS

We reviewed the clinical and genetic data collected in 2006-2017, from the BHDS patients who were Asian and presented with pulmonary cysts with or without a history of PTX.

RESULTS

Data from 334 (41.3% males; 58.7% females) patients from 297 unrelated families were reviewed. Among them, 314 (94.0%) patients developed PTX. The median age at the first occurrence of PTX was 32 years, which was significantly lower in males (P = 0.003) and patients without notable skin manifestations (P < 0.001). Seventy-six (24.2%) patients experienced their first PTX episode before the age of 25 years. PTX simultaneously occurred in the bilateral lungs of 37 (11.8%) patients. Among 149 patients who had their first PTX episode at least 10 years before BHDS diagnosis, PTX occurred more frequently in males (P = 0.030) and light smokers than in nonsmokers (P = 0.014). The occurrence of PTX peaked in the early 30s and gradually decreased with age but remained high in females (P = 0.001). We identified 70 unique FLCN germline variants, including duplications (46.4%), substitutions (7.1%), insertions/deletions (30.0%), and variants affecting splicing (12.5%). Approximately 80% of Asian patients suspected of having BHDS could be genetically diagnosed by examining FLCN exons 7, 9, 11, 12, and 13. No apparent genotype-phenotype correlation regarding pulmonary manifestations was identified.

CONCLUSIONS

Our findings indicate that sex, smoking history, and skin manifestations at BHDS diagnosis significantly influence the clinical features of BHDS-associated PTX. These findings may contribute to the appropriate management and treatment of BHDS-associated PTX.

Dynamics of thoracic endometriosis in the pleural cavity

Background

Thoracic endometriosis-related pneumothorax is a secondary spontaneous pneumothorax caused by thoracic endometriosis. Diaphragmatic endometriosis is well-studied, but visceral and/or parietal pleural lesions are not. Although surgery is an effective treatment, postoperative recurrence rates are unsatisfactory probably due to inadequate understanding of underlying pathophysiology. We aimed to clarify the clinicopathological features of thoracic endometriosis.

Methods

In total, 160 patients who underwent thoracoscopic surgery from a single institution with histopathologically proven thoracic endometriosis from January 2015 to December 2019 were included. Clinicopathological characteristics and surgical outcomes were assessed retrospectively.

Results

The cohort median age was 41 (range 22–53) years. Pneumothorax was right-sided in 159 (99.4%) and left-sided in only 1 (0.6%) case. Visceral and parietal pleural lesions were diagnosed in 79 (49.4%) and 71 (44.4%) patients, respectively. In total, 104 visceral pleural lesions and 101 parietal pleural lesions were detected. The S⁴ region and the dorsal 6^th intercostal space contained the largest number of visceral pleural (66 lesions) and parietal pleural lesions (25 lesions), respectively. Histopathological evaluation revealed endometriotic tissues, existing in the outer external elastic layer in all lesions, were localized or invaded deeply. The median follow-up period was 370 (range, 6–1824) days. The Kaplan-Meier method revealed that the 1- and 2-year postoperative recurrence rates were 13.8% and 19.3%, respectively.

Conclusions

Visceral pleural endometriotic lesions may be disseminated from the visceral pleural surface and infiltrate into the pleura. Intraoperatively, careful observation of the specific sites, such as the visceral pleura of S⁴ and the parietal pleura of 6^th intercostal space, is important to reduce postoperative recurrence.

Seventh BHD international symposium: recent scientific and clinical advancement

The 7th Birt-Hogg-Dubé (BHD) International Symposium convened virtually in October 2021. The meeting attracted more than 200 participants internationally and highlighted recent findings in a variety of areas, including genetic insight and molecular understanding of BHD syndrome, structure and function of the tumor suppressor Folliculin (FLCN), therapeutic and clinical advances as well as patients’ experiences living with this malady.

Current opinion and comparison of surgical procedures for the treatment of primary spontaneous pneumothorax

INTRODUCTION

Although three-port video-assisted thoracoscopic surgery (VATS) is the standard radical treatment for primary spontaneous pneumothorax (PSP), several issues need to be addressed as the postoperative recurrence rate remains relatively high. Although bullectomy is effective in preventing the postoperative recurrence of PSP, recurrent pneumothorax often occurs, requiring additional methods such as pleural covering with absorbable mesh sheets, surgical chemical pleurodesis, pleural abrasion, or pleurectomy. In addition, minimally invasive approaches that exceed three-port VATS are required according to the social demand. These approaches, such as uniportal VATS, reduced port surgery, and needlescopic surgery, have cosmetic merits, lower postoperative pain, and similar surgical results as three-port VATS.

AREAS COVERED

We focused on conventional and novel treatments for PSP in this article.

EXPERT OPINION

Effective methods that prevent postoperative recurrence and minimally invasive approaches will become popular in the near future.

National survey of bladder endometriosis cases in Japan

AIM

We aimed to describe the clinical presentation, operative or medical management, and postoperative recurrence of bladder endometriosis (BE).

METHODS

We conducted a national survey to investigate BE cases from 2006 to 2016 in Japan. Histologically diagnosed cases were extracted and then investigated for the following factors: age at diagnosis, body mass index, symptoms, imaging modalities, surgical therapy, hormonal therapy, follow-up period, and postoperative recurrence.

RESULTS

Eighty-nine patients with pathologically benign BE were identified. Eighty patients underwent surgery, whereas nine did not. Moreover, 34 and 44 patients underwent transurethral resection (TUR) and partial cystectomy (PC), respectively. Cumulative recurrence rates were significantly higher with TUR than with PC (p < 0.05). The recurrence rate tended to be higher after laparoscopic PC (n = 24) than after open PC (n = 20), but the difference was not statistically significant (p = 0.0879). Of the nine nonsurgical patients, eight received hormonal therapy and one did not. Efficacy rates of dienogest, GnRH agonist, and OC were 85.7%, 66.7%, and 66.7%, respectively. Of five patients with BE extending to the ureter or ureteral orifices, two underwent PC and ureteroneocystostomy and one underwent total nephroureterectomy due to renal function loss.

CONCLUSION

To our knowledge, this is the first study to compare the postoperative recurrence of BE after TUR and PC. We found that cumulative recurrence rate is significantly lower after PC than after TUR. BE extending to the ureter or ureteral orifices is a very challenging condition. Further studies are required for the optimal management of BE.

The effects of total pleural covering on pneumothorax recurrence and pulmonary function in lymphangioleiomyomatosis patients without history of pleurodesis or thoracic surgeries for pneumothorax

Background

Total pleural covering (TPC) is an innovative surgical procedure in which the entire visceral pleura is wrapped with sheets of oxidized regenerated cellulose (ORC) mesh under video-assisted thoracoscopic surgery. We have previously reported that TPC could successfully prevent pneumothorax recurrence in patients with lymphangioleiomyomatosis (LAM). However, the actual efficacy and preventive effect of TPC on pneumothorax recurrence remains unclear as many LAM patients already had pleural adhesion prior to TPC that was induced by thoracic surgery and/or pleurodesis. The purpose of this study is to evaluate the effects of TPC on pneumothorax recurrence and pulmonary function in LAM patients with no history of thoracic surgeries or pleurodesis.

Methods

We retrospectively reviewed medical charts of 52 patients (60 hemithoraces) who underwent TPC at our center, from January 2003 to September 2019, as a first surgical intervention for pneumothorax.

Results

Pneumothorax recurrence occurred in 12 patients [14 of 60 hemithoraces (23.3%)] during the observation period [27 months (14.7; 56.4) = median (lower; upper quartiles)]. The probability of recurrence-free hemithorax post TPC was 81.1% at 2.5 years and 64.1% at 5 years. TPC did not produce a significant decrease in either VC %predicted (pred) or FEV₁/FVC. The pre- vs. post-TPC median (lower; upper quartiles) VC %pred was 85.7% (79.7; 98.0) vs. 87.2% (72.3; 95.6), P=0.535 and the FEV₁/FVC was 84.6% (75.7; 89.6) vs. 83.0% (71.8; 87.0), P=0.667. Mechanistic/mammalian target of rapamycin (mTOR) inhibitors (mTORI) were subsequently initiated in 19 patients (36.5%) because of the progression of LAM. The postoperative FEV_1%pred was significantly lower in patients who required mTORI than in those who did not [68.1% (57.3; 82.9) vs. 88.7% (84.6; 89.8), P=0.020]; the decline rate in FEV_1%pred/year from pre to post TPC was significantly greater in LAM patients who required mTORI than in those who did not [-9.37% (-4.73; 12.9) vs. -1.94% (1.52; -4.50), P=0.029]. Postoperative complications were found in 25 of 52 hemithoraces (48.1%).

Conclusions

TPC can prevent pneumothorax recurrence without causing ventilatory impairment or severe pleural symphysis in LAM patients. TPC is an effective treatment option for LAM-associated pneumothorax based on its efficacy and safety.

PAX8: A Highly Sensitive Marker for the Glands in Extragenital Endometriosis

In cases of extragenital endometriosis or microscopic endometriosis lesions, pathological diagnosis can be challenging because endometriotic stroma and glands represent only a minor component of fibrotic endometriotic lesions. For better accuracy of diagnosis, the development of a sensitive and specific epithelial marker is beneficial. Previous studies showed that PAX8 is a highly sensitive and specific marker for primary and metastatic Mullerian epithelial tumors. Therefore, we sought to examine whether PAX8 is a highly sensitive marker for glands in extragenital endometriosis. Eight and 47 samples of ovarian endometrioma and extragenital endometriosis, respectively, were evaluated in this study. We calculated the percentage of samples positively immunostained for PAX8, CD10, estrogen receptor (ER), and progesterone receptor (PR). PAX8 was positive for endometriotic epithelial cells in 95.7% (45/47) of extragenital endometrioses and in 100% (8/8) of ovarian endometrioses. CD10 was positive for endometriotic stromal cells in 97.9% (46/47) of extragenital endometrioses. PAX8 was strongly positive for glands, even in a CD10-negative case. The expression of PAX8, CD10, and PR was not affected by preoperative hormonal therapy, and the positive rate of ER staining was significantly reduced by preoperative hormonal therapy. In conclusion, PAX8 is a highly sensitive epithelial marker for extragenital endometriosis. This specific expression was maintained under hormonal therapy. It is noteworthy that extragenital endometriosis maintains the expression of this lineage marker, although it occurs at various sites, and its cause and mechanism of development might be different. PAX8 nuclear expression can be useful in detecting extragenital endometriosis in clinical practice.

IFITM1 is a Novel, Highly Sensitive Marker for Endometriotic Stromal Cells in Ovarian and Extragenital Endometriosis

When the presence of endometriotic lesions are not evident by hematoxylin and eosin staining, CD10 is used to highlight and confirm the presence of endometriotic stroma. However, CD10 is not specific only to the endometrial stroma but is also expressed in many other cells. Recently, interferon-inducible transmembrane protein 1 (IFITM1) was reported as a highly specific immunohistochemical marker of normal endometrial stroma and endometrial stromal neoplasm. In this study, we examined the expression of IFITM1 and CD10 in 18 cases of ovarian endometriosis and 44 cases of extragenital endometriosis. Among the 62 patients, 62 (100.0%) were positive for IFITM1 and 60 (96.8%) for CD10, and CD10 was negative in 2 cases that were positive for IFITM1. Additionally, we found that IFITM1 sensitivity was unaffected by the presence or absence of hormonal therapy. To the best of our knowledge, this represents the first demonstration of IFITM1 as a highly sensitive stromal marker of ovarian and extragenital endometriosis.

Is conventional management of primary spontaneous pneumothorax appropriate?

OBJECTIVE

This study aimed to evaluate the recurrence rate after primary and secondary conservative treatments and to clarify the validity of current primary spontaneous pneumothorax management by comparing secondary conservative treatment and surgical outcomes.

METHODS

Data from 166 patients with primary spontaneous pneumothorax treated at a single site between September 2015 and March 2019 were retrospectively evaluated. Patient characteristics of those who received primary conservative therapy (n = 166) and secondary conservative therapy (n = 28) were summarized. The outcomes from patients who experienced recurrence (n = 64) were compared based on those who underwent surgery (n = 24) and those who underwent secondary conservative therapy (n = 28).

RESULTS

The post-treatment day 60 recurrence rate was 27.1 and 49.5% cases in the primary and secondary treatment groups, respectively, which was significantly higher after secondary treatment than after primary treatment with conservative therapy (p = 0.032). The post-treatment one-year recurrence rate was 13.5 and 57.9% in patients who underwent surgery and secondary conservative treatment, respectively; secondary conservative treatment resulted in a significantly higher recurrence rate than surgery (p < 0.001).

CONCLUSIONS

There is evidence for guidelines that recommend surgery for recurrent primary spontaneous pneumothorax after primary conservative therapy based on its lower and more delayed post-treatment recurrence rate than secondary treatment with conservative therapy.

Clinical practice guidelines for the treatment of extragenital endometriosis in Japan, 2018

The aim of this publication is to disseminate the clinical practice guidelines for the treatment of intestinal, bladder/ureteral, thoracic and umbilical endometriosis, already published in Japanese, to non-Japanese speakers. For developing the original Japanese guidelines, the clinical practice guideline committee was formed by the research team for extragenital endometriosis, which is part of the research program of intractable disease of the Japanese Ministry of Health, Labor and Welfare. The clinical practice guideline committee formulated eight clinical questions for the treatment of extragenital endometriosis, which were intestinal, bladder/ureteral, thoracic and umbilical endometriosis. The committee performed a systematic review of the literature to provide responses to clinical questions and developed clinical guidelines for extragenital endometriosis, according to the process proposed by the Medical Information Network Distribution Service. The recommendation level was determined using modified Delphi methods. The clinical practice guidelines were officially approved by the Japan Society of Obstetrics and Gynecology and the Japan Society of Endometriosis. This English version was translated from the Japanese version.

Does a gender have something to do with clinical pictures of primary spontaneous pneumothorax?

OBJECTIVE

Primary spontaneous pneumothorax is relatively rarer in women than in men. In addition, women develop secondary spontaneous pneumothorax, such as lymphangioleiomyomatosis, which is rare and difficult to diagnose. Therefore, the clinical characteristics of primary spontaneous pneumothorax in women remain unknown presently. We compared the clinical characteristics of primary spontaneous pneumothorax between the two sexes at two pneumothorax centers.

METHODS

Between January 2015 and July 2019, we retrospectively evaluated 627 cases (106 women and 521 men) who underwent first video-assisted thoracoscopic surgery for primary spontaneous pneumothorax and extracted the medical backgrounds and postoperative recurrence between the sexes. Univariate and multivariate analysis was used to examine the effect of sexual specificity on postoperative recurrence.

RESULTS

Among women and men with PSP, the mean ages were 27.8 ± 10.7 and 24.3 ± 10.0 years, respectively; their mean heights were 162.0 ± 5.9 and 173.3 ± 6.1 cm, respectively. These differences were statistically significant. Three women (2.8%) and 54 men (10.4%) developed postoperative recurrence, which showed significant difference on Kaplan-Meier analysis (p = 0.027). Univariate and multivariate analysis showed the factors; women (p = 0.045, hazard ratio: 0.289 [95% confidence interval 0.086-0.973]) and smoker (p = 0.035, hazard ratio: 0.269 [95% confidence interval 0.079-0.909]) had the preventing factor for postoperative recurrence, respectively.

CONCLUSIONS

Women with PSP had lower postoperative recurrence rate than men. Although we could not reveal why women had lower postoperative recurrence rates than men in this study, the sexual difference such as hormonal cycle, development of body structure possibly affects the clinical characteristics of women with primary spontaneous pneumothorax.

A novel dual-covering method in video-assisted thoracic surgery for pediatric primary spontaneous pneumothorax

BACKGROUND

Primary spontaneous pneumothorax (PSP) generally occurs in young adults, whereas pediatric PSP is uncommon. It is difficult to source reliable data on pediatric PSP, the management of which is based on guidelines for adult PSP; however, the rate of recurrence after video-assisted thoracoscopic surgery (VATS) for pediatric PSP is reported to be higher.

METHODS

We reviewed retrospectively a collective total of 66 surgical cases of a first pneumothorax episode in 46 children under 16 years of age, who were treated at our hospital between February, 2005 and November, 2017.

RESULTS

The surgical cases were divided into two groups, depending on how the treated lesions were covered. In the dual-covering (DC) group, the PSP was covered by oxidized regenerated cellulose and polyglycolic acid (8 patients; 13 cases) and in the single-covering (SC) group, the PSP was covered by oxidized regenerated cellulose (38 patients; 53 cases). There was no incidence of recurrence after surgery in the DC group, but 17 cases (32.1%) of recurrence after surgery in the SC group. This difference was significant.

CONCLUSION

The DC method prevented the recurrence of PSP more effectively than the SC method after VATS in pediatric patients. Long-term follow-up after VATS for pediatric PSP is also important because of the risk of delayed recurrence.

IFITM1 is a Novel, Highly Sensitive Marker for Endometriotic Stromal Cells in Ovarian and Extragenital Endometriosis

When the presence of endometriotic lesions are not evident by hematoxylin and eosin staining, CD10 is used to highlight and confirm the presence of endometriotic stroma. However, CD10 is not specific only to the endometrial stroma but is also expressed in many other cells. Recently, interferon-inducible transmembrane protein 1 (IFITM1) was reported as a highly specific immunohistochemical marker of normal endometrial stroma and endometrial stromal neoplasm. In this study, we examined the expression of IFITM1 and CD10 in 18 cases of ovarian endometriosis and 44 cases of extragenital endometriosis. Among the 62 patients, 62 (100.0%) were positive for IFITM1 and 60 (96.8%) for CD10, and CD10 was negative in 2 cases that were positive for IFITM1. Additionally, we found that IFITM1 sensitivity was unaffected by the presence or absence of hormonal therapy. To the best of our knowledge, this represents the first demonstration of IFITM1 as a highly sensitive stromal marker of ovarian and extragenital endometriosis.

PAX8: A Highly Sensitive Marker for the Glands in Extragenital Endometriosis

In cases of extragenital endometriosis or microscopic endometriosis lesions, pathological diagnosis can be challenging because endometriotic stroma and glands represent only a minor component of fibrotic endometriotic lesions. For better accuracy of diagnosis, the development of a sensitive and specific epithelial marker is beneficial. Previous studies showed that PAX8 is a highly sensitive and specific marker for primary and metastatic Mullerian epithelial tumors. Therefore, we sought to examine whether PAX8 is a highly sensitive marker for glands in extragenital endometriosis. Eight and 47 samples of ovarian endometrioma and extragenital endometriosis, respectively, were evaluated in this study. We calculated the percentage of samples positively immunostained for PAX8, CD10, estrogen receptor (ER), and progesterone receptor (PR). PAX8 was positive for endometriotic epithelial cells in 95.7% (45/47) of extragenital endometrioses and in 100% (8/8) of ovarian endometrioses. CD10 was positive for endometriotic stromal cells in 97.9% (46/47) of extragenital endometrioses. PAX8 was strongly positive for glands, even in a CD10-negative case. The expression of PAX8, CD10, and PR was not affected by preoperative hormonal therapy, and the positive rate of ER staining was significantly reduced by preoperative hormonal therapy. In conclusion, PAX8 is a highly sensitive epithelial marker for extragenital endometriosis. This specific expression was maintained under hormonal therapy. It is noteworthy that extragenital endometriosis maintains the expression of this lineage marker, although it occurs at various sites, and its cause and mechanism of development might be different. PAX8 nuclear expression can be useful in detecting extragenital endometriosis in clinical practice.

Diagnosis of superficial esophageal squamous cell carcinoma invasion depth before endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a widely accepted procedure for superficial esophageal squamous cell carcinoma (SESCC) limited to the epithelium or lamina propria mucosae (EP/LPM). We aimed to compare the efficacy of endoscopic ultrasonography (EUS) and magnifying endoscopy with narrow band imaging (ME-NBI) for predicting the tumor invasion depth in patients with SESCC. Specifically, we evaluated the ability of these examinations to distinguish EP/LPM from SESCC invading the muscularis mucosae or superficial submucosa (MM/SM1) and more deeply invasive lesions before ESD.We retrospectively analyzed a database of all patients with SESCC who had undergone both EUS and ME-NBI for pretreatment staging and ESD resection at Hiroshima University Hospital between September 2007 and June 2015. The clinicopathologic characteristics of SESCCs were classified according to the Japanese Classification of Esophageal Cancer.A total of 174 lesions in 174 patients were included: 124 (71%) EP/LPMs, 35 (20%) MM/SM1s, and 15 (9%) SESCCs invading the mid submucosae (SM2). The sensitivity of EUS and of ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 72% and 83%, respectively. The accuracy of EUS and ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 70% and 82%, respectively. Sensitivity and accuracy of ME-NBI in distinguishing EP/LPM from MM/SM1 and more deeply invasive SESCCs is significantly higher than those of EUS (P = 0.048 and P = 0.017, respectively).ME-NBI may be more useful than EUS for the determination of SESCC invasion depth before ESD.

Curative Criteria After Endoscopic Resection for Superficial Esophageal Squamous Cell Carcinomas

BACKGROUND

According to the Japanese Esophageal Society (JES) guidelines, risk factors for lymph node (LN) metastasis in the muscularis mucosa (MM)/submucosa to a depth of up to 200 μm (SM1) in cases of esophageal squamous cell carcinomas (ESCCs) include the presence of lymphatic invasion (ly), venous invasion (v), infiltration pattern (INF)c, and SM1. The long-term prognoses of these patients are unclear, and there are very few reports on the validation of the curative criteria for MM/SM1 ESCCs.

AIMS

To examine the long-term prognoses of these patients and the risk factors for LN metastasis of MM/SM1 ESCCs after endoscopic resection (ER).

METHODS

This study included patients with MM/SM1 ESCCs who underwent ER at Hiroshima University Hospital from December 1990 to November 2016. We evaluated the clinicopathological characteristics of 98 patients and overall survival, disease-specific survival, recurrence-free survival, and recurrence rates in the e-curative and non-e-curative groups.

RESULTS

The mean observation period was 75 months. There was no significant difference in disease-specific survival rate between the e-curative and non-e-curative groups (100 vs. 98%). There was no significant difference in disease-specific survival rates between the groups (100 vs. 98%). In contrast, the LN recurrence-free survival rate in patients with INFa, ly(-), and v(-) was significantly higher than that in patients with INFb/c, ly(+), or v(+) (100 and 87%, P < 0.05).

CONCLUSION

Contrary to the JES guidelines, our findings suggest that new criteria (MM/SM1, INFa, negative vertical margin (VM0), ly[-], and v[-]) may be associated with curative ER without additional treatment.

A total pleural covering of absorbable cellulose mesh prevents pneumothorax recurrence in patients with Birt-Hogg-Dubé syndrome

Background

Birt-Hogg-Dubé syndrome (BHDS) is a recently recognized inherited multiple cystic lung disease causing recurrent pneumothoraces. Similarly to the lesions in patients with lymphangioleiomyomatosis (LAM), the pulmonary cysts are innumerable and widely dispersed and cannot all be removed. We recently described a total pleural covering (TPC) that covers the entire visceral pleura with oxidized regenerated cellulose (ORC) mesh. TPC successfully prevented the recurrence of pneumothorax in LAM patients. The purpose of this study was to evaluate the effect of an ORC pleural covering on pneumothorax recurrence in BHDS patients.

Results

This retrospective study enrolled a total of 81 pneumothorax patients with the diagnosis of BHDS who underwent 90 covering surgeries from January 2010 to August 2017 at Tamagawa Hospital. During the first half of the study period, a lower pleural covering (LPC) which covered the affected area with ORC mesh was mainly used to treat 38 pneumothoraces. During the second half of the study period, TPC was primarily performed for 52 pneumothoraces. All the thoracoscopic surgeries were successfully performed without serious complications (≥ Clavien-Dindo grade III). The median follow-up periods after LPC/TPC were 66/34 months, respectively. Pneumothorax recurrence rates after LPC at 2.5/5/7.5 years postoperatively were 5.4/12/42%, respectively; none of the patients who had underwent TPC developed postoperative pneumothorax recurrence (P = 0.032).

Conclusions

TPC might be an effective option for surgical treatment of intractable pneumothorax in patients with BHDS.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0790-x) contains supplementary material, which is available to authorized users.

Skin lesions of Birt-Hogg-Dubé syndrome: Clinical and histopathological findings in 31 Japanese patients who presented with pneumothorax and/or multiple lung cysts

BACKGROUND

Birt-Hogg-Dubé syndrome (BHDS) (OMIM #135150) is an autosomal dominant disease, characterized by fibrofolliculomas (FFs) of the skin, pulmonary cysts with/without pneumothorax, and renal tumors. The prevalence of skin manifestations reported for Japanese BHDS patients is lower (<30%) compared with that of Western countries (75∼90%), which appear to be underestimated.

OBJECTIVE

To precisely examine the prevalence of skin lesions with dermoscopy and histopathology with reference to genetic analyses.

METHODS

We studied 31 patients (47.0±13.2years old, range 15-71) consisting of 26 unrelated families consecutively from May 2013 to June 2015 specifically for skin-colored papules on their faces and cervicothoracic regions. Patients initially suspected of BHDS from multiple pulmonary cysts that resulted in pneumothorax (30/31; 96.8%) received dermoscopic examinations and skin biopsies if applicable. The diagnosis of BHDS was established by folliculin (FLCN) genetic testing, and the results were compared to the histopathological findings of FFs or trichodiscomas (TDs).

RESULTS

FLCN germline mutation was demonstrated in 25/26 (96.2%) unrelated families tested and 28/29 patients (96.6%) tested. Skin lesions were recognized in 26/31 patients (83.9%); skin biopsies were performed in 23 patients of whom FFs and/or TDs were histologically demonstrated in 17 (73.9%). Although our study population included patients whose skin manifestations were evaluated prior to or after FLCN genetic testing, skin lesions were clearly prevalent and recognizable irrespective of whether genetic testing was or wasn't done. When examined with dermoscopy, distinct FFs appeared as well-demarcated areas of pallor with central follicular openings in 13 of 15 FF-bearing patients (86.7%); however, those manifestations were not recognized for TD.

CONCLUSIONS

Skin lesions appear to be more prevalent than previously reported (<30% vs.73.9%) in Japanese BHDS patients. Dermoscopy is a useful diagnostic aid for finding FFs.

Oxidized regenerated cellulose induces pleural thickening in patients with pneumothorax: possible involvement of the mesothelial-mesenchymal transition

PURPOSE

The pleural covering technique, i.e., wrapping a part of or the entire surface of the lung with oxidized regenerative cellulose (ORC), reinforces visceral pleura through pleural thickening for patients with pneumothorax and cystic lung diseases. However, it remains undetermined how ORC induces pleural thickening.

METHODS

A histopathological examination was performed for lung specimens from patients who had recurrent pneumothoraces after pleural covering and re-operation (n = 5). To evaluate the influence of ORC on the pleura in vitro, we used MeT-5A cells (a human pleural mesothelial cell line).

RESULTS

Pleural thickening was confirmed in all lung specimens examined. Three months after covering, the thickened pleura showed inflammatory cell infiltration, proliferation of myofibroblasts, and expression of fibronectin and TGF-β. However, after 1 year, those findings virtually disappeared, and the thickened pleura was composed mainly of abundant collagen. When MeT-5A cells were cultured in ORC-immersed medium, their morphology changed from a cobblestone to spindle-shaped appearance. The expression of E-cadherin decreased, whereas that of N-cadherin, α-smooth muscle actin, and fibronectin increased, suggesting mesothelial-mesenchymal transition (Meso-MT).

CONCLUSIONS

Our results suggest that Meso-MT may be involved as a mechanism of pleural thickening induced by pleural covering with ORC.

Novel clinical scoring system to identify patients with pneumothorax with suspicion for Birt-Hogg-Dubé syndrome

BACKGROUND AND OBJECTIVE

Birt-Hogg-Dubé syndrome (BHDS) is a rare hereditary disease that presents with multiple lung cysts and pneumothorax (PTX). Although some reports propose that findings from chest computed tomography enable one to distinguish BHDS from primary spontaneous pneumothorax (PSP), it is still unclear whether clinical features are useful for identifying patients with suspicion of BHDS from those with PTX.

METHODS

We retrospectively reviewed the medical records of patients with PTX who underwent video-assisted thoracoscopic surgery at Nissan Tamagawa Hospital from January 2012 to December 2015.

RESULTS

We identified a total of 1141 patients with PTX, including 54 with BHDS and 517 with PSP. Among them, logistic regression analysis segregated five features that were significantly associated with BHDS: familial history of PTX, past history of bilateral PTX, age at the first episode of PTX (≥25 years old (y.o.)), body mass index (≥18.5) and gender (female). We assigned scores of 3, 3, 2, 2 and 1 to the five features, respectively, to establish a system with a calculated score from 0 to 11. The cut-off value of a calculated score ≥ 4 yielded the highest sensitivity of 93% and specificity of 86%. Receiver operating characteristic (ROC) analysis showed the area under the curve reflecting an accuracy of this diagnostic test as 0.953.

CONCLUSION

BHDS has several clinical features distinct from PSP. Our scoring system consists of only five clinical variables that are easily evaluated and efficiently separate BHDS patients from those who have PTX without relying on an imaging study. Further prospective study is needed to confirm our findings.

Haploinsufficiency of the folliculin gene leads to impaired functions of lung fibroblasts in patients with Birt-Hogg-Dubé syndrome

Birt–Hogg–Dubé syndrome (BHDS) is an autosomal dominant inherited disorder caused by germline mutations in the FLCN gene, and characterized by skin fibrofolliculomas, multiple lung cysts, spontaneous pneumothorax, and renal neoplasms. Pulmonary manifestations frequently develop earlier than other organ involvements, prompting a diagnosis of BHDS. However, the mechanism of lung cyst formation and pathogenesis of pneumothorax have not yet been clarified. Fibroblasts were isolated from lung tissues obtained from patients with BHDS (n = 12) and lung cancer (n = 10) as controls. The functional abilities of these lung fibroblasts were evaluated by the tests for chemotaxis to fibronectin and three‐dimensional (3‐D) gel contraction. Fibroblasts from BHDS patients showed diminished chemotaxis as compared with fibroblasts from controls. Expression of fibronectin and TGF‐β1 was significantly reduced in BHDS fibroblasts when assessed by qPCR. Addition of TGF‐β1 in culture medium of BHDS lung fibroblasts significantly restored these cells' abilities of chemotaxis and gel contraction. Human fetal lung fibroblasts (HFL‐1) exhibited reduced chemotaxis and 3‐D gel contraction when FLCN expression was knocked down. To the contrary, a significant increase in chemotactic activity toward to fibronectin was demonstrated when wild‐type FLCN was overexpressed, whereas transduction of mutant FLCN showed no effect on chemotaxis. Our results suggest that FLCN is associated with chemotaxis in lung fibroblasts. Together with reduced TGF‐β1 expression by BHDS lung fibroblasts, a state of FLCN haploinsufficiency may cause lung fibroblast dysfunction, thereby impairing tissue repair. These may reveal one mechanism of lung cyst formation and pneumothorax in BHDS patients.

A Total Pleural Covering for Lymphangioleiomyomatosis Prevents Pneumothorax Recurrence

Background

Spontaneous pneumothorax is a major and frequently recurrent complication of lymphangioleiomyomatosis (LAM). Despite the customary use of pleurodesis to manage pnenumothorax, the recurrence rate remains high, and accompanying pleural adhesions cause serious bleeding during subsequent lung transplantation. Therefore, we have developed a technique of total pleural covering (TPC) for LAM to wrap the entire visceral pleura with sheets of oxidized regenerated cellulose (ORC) mesh, thereby reinforcing the affected visceral pleura and preventing recurrence.

Methods

Since January 2003, TPC has been applied during video-assisted thoracoscopic surgery for the treatment of LAM. The medical records of LAM patients who had TPC since that time and until August 2014 are reviewed.

Results

TPC was performed in 43 LAM patients (54 hemithoraces), 11 of whom required TPC bilaterally. Pneumothorax recurred in 14 hemithoraces (25.9%) from 11 patients (25.6%) after TPC. Kaplan-Meier estimates of recurrence-free hemithorax were 80.8% at 2.5 years, 71.7% at 5 years, 71.7% at 7.5 years, and 61.4% at 9 years. The recurrence-free probability was significantly better when 10 or more sheets of ORC mesh were utilized for TPC (P = 0.0018). TPC significantly reduced the frequency of pneumothorax: 0.544 ± 0.606 episode/month (mean ± SD) before TPC vs. 0.008 ± 0.019 after TPC (P<0.0001). Grade IIIa postoperative complications were found in 13 TPC surgeries (24.1%).

Conclusions

TPC successfully prevented the recurrence of pneumothorax in LAM, was minimally invasive and rarely caused restrictive ventilatory impairment.

Left-Sided Catamenial Pneumothorax with Thoracic Endometriosis and Bullae in the Alveolar Wall

Catamenial pneumothorax (CP) is generally caused by intraperitoneal air leaking from the uterus into the thoracic cavity via a defect in the endometrial tissue of the diaphragm and is usually detected in the right thorax. We report a case of left-sided CP caused by endometriosis in the visceral pleura and with no abnormal findings in the diaphragm. A 33-year-old female patient presented at the end of a course of low-dose contraceptive pills for pelvic endometriosis, with spontaneous pneumothorax in the left chest. Chest CT revealed a bulla in the left upper lung lobe. The patient underwent partial resection of the lung. Immunohistochemistry confirmed the presence of endometrial stromal tissue in the visceral pleura and confirmed this as the cause of pneumothorax since there were no observable abnormalities in the diaphragm. This case suggests that immunohistochemical examination of patients with spontaneous pneumothorax can detect alternative endometrial lesions.

Two Kinds of Cystic Lung Lesions with Pulmonary Lymphangioleiomyomatosis in a Male

A 34-year-old male with frequent recurrence of right pneumothorax was admitted to our hospital. He was a current smoker and outwardly male without genital aplasia. He was diagnosed as tuberous sclerosis complex (TSC) at 2 year-old and underwent transcatheter arterial embolization for right renal hemorrhage due to renal tumor 2 years ago. Chest Computed Tomography showed that he had multiple tiny round cystic lesions with thin wall in both lungs. The recurrent pneumothorax was expected to be associated with TSC-Lymphangioleiomyomatosis (LAM). Video-assisted thoracic surgery was successfully performed. The operative and histological findings revealed that the bullae were classified into two groups; emphysematous bullae and bullae due to LAM. His postoperative course was uneventful. TSC-LAM is extremely rare, but in some cases the clinical recognition might be escaped due to subtle findings of bullae in early LAM, resulting in diagnosis as spontaneous pneumothorax.

Isolation of individual cellular components from lung tissues of patients with lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare neoplastic disease entailing cystic destruction of the lungs and progressive respiratory failure. LAM lungs are histologically characterized by the proliferation of smooth muscle-like cells (LAM cells) and an abundance of lymphatic vessels. To elucidate the pathophysiological processes of LAM, cell-type-specific analyses are required. However, no method exists for isolating the individual types of cells in LAM lesions. Therefore, we established a fluorescence-activated cell sorting (FACS)-based method for the direct isolation of LAM cells and other various cellular components from LAM-affected lung tissue. We obtained LAM-affected lung tissue from resections or transplant recipients and prepared single-cell suspensions. FACS, immunohistochemical, and molecular analysis were used cooperatively to isolate HMB45-positive LAM cells with tuberous sclerosis complex (TSC) 2 loss of heterozygosity (LOH). Using a combination of antibodies against an epithelial cell adhesion molecule (EpCAM) and podoplanin, we fractionated CD45-negative lung cells into three groups: lymphatic endothelial cells (LEC) (EpCAM(-)/podoplanin(hi) subset), alveolar type II cells (EpCAM(hi)/podoplanin(-) subset), and mesenchymal cells (EpCAM(-)/podoplanin(-/low) subset). During subsequent analysis of HMB45 expression, as a LAM-specific marker, we clearly identified LAM cells in the mesenchymal cell population. We then discovered that CD90(+)/CD34(-) cells in the mesenchymal cell population are not only positive for HBM45 but also had TSC2 LOH. These isolated cells were viable and subsequently amenable to cell culture. This method enables us to isolate LAM cells and other cellular components, including LAM-associated LEC, from LAM-affected lung tissues, providing new research opportunities in this field.

Pleural Covering Application for Recurrent Pneumothorax in a Patient with Birt-Hogg-Dubé Syndrome

Birt-Hogg-Dubé syndrome (BHDS) is a rare hereditary disease that presents with multiple lung cysts and recurrent pneumothorax. These cysts occupy predominantly the lower-medial zone of the lung field adjacent to the interlobar fissure, and some of them abut peripheral pulmonary vessels. For the surgical management of pneumothorax with BHDS, the conventional approach of resecting all subpleural cysts and bullae is not feasible. Thus, after handling several bullae by using a stapler or performing ligation as a standardized treatment, we applied to a pleural covering technique to thicken the affected visceral pleura and then to prevent recurrence of pneumothorax. We herein report the successful application of a pleural covering technique via thoracoscopic surgery to treat the recurrent pneumothorax of a 30-year-old man with BHDS. This technique is promising for the management of intractable pneumothorax secondary to BHDS.

Computed tomographic features of lymphangioleiomyomatosis: evaluation in 138 patients

PURPOSE

The aim was to characterize the computed tomographic (CT) findings from Japanese patients with lymphangioleiomyomatosis (LAM).

MATERIALS AND METHODS

CT scans of the chest, abdomen, and pelvis from 124 patients with sporadic LAM (S-LAM, mean age, 37.4 years) and 14 patients with tuberous sclerosis complex (TSC)-LAM (mean age, 35.6 years) were analyzed.

RESULTS

Pulmonary nodules (18.8%) and hepatic angiomyolipoma (AML, 24.3%) were more common in our patients than those in previous reports. Compared with TSC-LAM, S-LAM group had a higher frequency of pulmonary nodules (28.6% vs 32.3%, P<0.01) and lower frequencies of air-space consolidation (21.4% vs 2.4%, P<0.01), pneumothorax (28.6% vs 8.1%, P=0.02), pulmonary hilar lymphadenopathy (14.3% vs 0.8%, P<0.01), renal AML (85.7% vs 17.4%, P<0.01), hepatic AML (71.4% vs 17.4%, P<0.01), and retrocrural lymphadenopathy (14.3% vs 1.4%, P=0.04). Axial lymphatic abnormalities (i.e., thoracic duct dilatation, lymphadenopathy, and lymphangioleiomyoma) were most common in the pelvis and tended to decrease in incidence with increased distance from the pelvis.

CONCLUSION

The incidence of some CT findings in Japanese patients differed from those in previous reports. Axial lymphatic abnormalities noted here suggest that the origin of LAM cells may be the pelvis.

Synthesis, Structure, and Redox Properties of [{(η(5) -C5 H5 )Co(S2 C6 H4 )}2 Mo(CO)2 ], a Novel Metalladithiolene Cluster

Metal-metal bond formation by a cobaltadithiolene complex was observed for the first time in the reaction of [Co(η(5) -C5 H5 )(S2 C6 H4 )] with [Mo(CO)3 (py)3 ] and BF3 to give the Co-Mo-Co cluster 1. Cyclic voltammetry reveals that 1 undergoes two one-electron reduction steps at the Co centers, which is indicative of transmission of the Co-Co electronic interaction through the Mo center.

Thoracic endometriosis-related pneumothorax distinguished from primary spontaneous pneumothorax in females

PURPOSE

Thoracic endometriosis-related pneumothorax (TERP) is a secondary condition specific for females, but in a clinical setting, TERP often is difficult to distinguish from primary spontaneous pneumothorax (PSP) based on a relationship between the dates of pneumothorax and menstruation. The purpose of this study was to clarify the clinical features of TERP compared with PSP.

METHODS

We retrospectively reviewed the clinical and histopathological files of female patients with pneumothorax who underwent video-assisted thoracoscopic surgery in the Pneumothorax Research Center during the 6-year period from January 2005 to December 2010. We analyzed the clinical differences between TERP and PSP.

RESULTS

The study included a total of 393 female patients with spontaneous pneumothorax, of whom 92 (23.4 %) were diagnosed as having TERP and 33.6 % (132/393) as having PSP. We identified four factors (right-sided pneumothorax, history of pelvic endometriosis, age ≥31 years, and no smoking history) that were statistically significant for predicting TERP and assigned 6, 5, 4, and 3 points, respectively, to establish a scoring system with a calculated score from 0 to 18. The cutoff values of a calculated score ≥12 yielded the highest positive predictive value (86 %; 95 % confidence interval (CI) 81.5-90.5 %) for TERP and negative predictive value (95.2 %; 95 % CI 92.3-98 %) for PSP.

CONCLUSIONS

TERP has several distinct clinical features from PSP. Our scoring system consists of only four clinical variables that are easily obtainable and enables us to suspect TERP in female patients with pneumothorax.

Characterization of pulmonary cysts in Birt-Hogg-Dubé syndrome: histopathological and morphometric analysis of 229 pulmonary cysts from 50 unrelated patients

Aims

To characterize the pathological features of pulmonary cysts, and to elucidate the possible mechanism of cyst formation in the lungs of patients with Birt–Hogg–Dubé syndrome (BHDS), a tumour suppressor gene syndrome, using histological and morphometric analyses.

Methods and results

We evaluated 229 lung cysts from 50 patients with BHDS and 117 from 34 patients with primary spontaneous pneumothorax (PSP) for their number, size, location and absence or presence of inflammation. The BHDS cysts abutted on interlobular septa (88.2%) and had intracystic septa (13.6%) or protruding venules (39.5%) without cell proliferation or inflammation. The frequencies of these histological characteristics differed significantly from those seen in the lungs of patients with PSP (P < 0.05). Although the intrapulmonary BHDS cysts were smaller than the subpleural BHDS cysts (P < 0.001), there was no difference in size between them when there was no inflammation. The number of cysts diminished logarithmically and the proportion of cysts with inflammation increased as their individual sizes became greater (P < 0.05).

Conclusions

These results imply that the BHDS cysts are likely to develop in the periacinar region, an anatomically weak site in a primary lobule, where alveoli attach to connective tissue septa. We hypothesize that the BHDS cysts possibly expand in size as the alveolar walls disappear at the alveolar-septal junction, and grow even larger when several cysts fuse.