Efficacy of hyperthermia pleurodesis: A comparative experimental study on serous membrane of abdominopelvic and thoracic cavities of rats.

BACKGROUND: Pleurodesis is a common technique for treating the accumulation of air or liquid in the pleural space caused by pneumothorax or pleural effusion, it is based on the bounding of pleural layers through induced inflammatory lesions. There are several pleurodesis procedures. OBJECTIVES: To test and describe the inflammatory effect of hyperthermia on the pleural and peritoneal mesothelia of rats, with the aim of testing the effectiveness of this process for inducing pleurodesis. METHODS: 35 Sprague-Dawley (male/female) rats were randomized into four treatment groups: Group A (Talc, 10 individuals); group B (control, 5 individuals); group C (hyperthermic isotonic saline, 10 individuals); and group D (filtrate air at 50°, 10 individuals). Inflammatory effect of hyperthermia was the primary outcome parameter. RESULTS: In the talc group, minimal adhesions between both pleural and peritoneal layers were observed in seven rats. Talc produced peritoneal mesothelium inflammation and fibrosis associated to foreign body giant cells in 80% (8/10) of the sample. Furthermore, clear evidence of a granulomatous foreign-body reaction was detected. No macroscopic and/or microscopic damage was registered in the remaining three groups (control, hyperthermic, and filtrate air). CONCLUSIONS: Talc is an excellent method for producing pleuro-peritoneal inflammatory lesions. On the contrary, hyperthermia apparently does not induce the macroscopic and microscopic damage that is required for efficient pleurodesis. Therefore, hyperthermia should not be used for pleurodesis procedures.

Uniportal VATS pleural biopsy in the diagnosis of exudative pleural effusion: awake or intubated?

BACKGROUND: The aim of this study is to compare the diagnostic efficacy and safety of video-assisted thoracoscopic surgery (VATS) with awake VATS (AVATS) pleural biopsy in undiagnosed exudative pleural effusions. METHODS: The diagnostic efficacy of pleural biopsy by uniportal VATS under general anesthesia or AVATS under local anesthesia and sedation performed by the same surgeon in patients with undiagnosed exudative pleural effusion between 2007 and 2020 were retrospectively evaluated. Test sensitivity, specificity, positive predictive value and negative predictive value were compared as well as age, gender, comorbidities, procedure safety, additional pleural-based interventions, duration time of operation and length of hospital stay. RESULTS: Of 154 patients with undiagnosed exudative pleural effusion, 113 (73.37%) underwent pleural biopsy and drainage with VATS, while 41 (26.62%) underwent AVATS pleural biopsy. Sensitivity, specificity, positive predictive value and negative predictive value were 92, 100, 100, and 85.71% for VATS, and 83.3, 100, 100, and 78.9% for AVATS, respectively. There was no significant difference in diagnostic test performance between the groups, (p = 0.219). There was no difference in the rate of complications [15 VATS (13.3) versus 4 AVATS (9.8%), p = 0.557]. Considering additional pleural-based interventions, while pleural decortication was performed in 13 (11.5%) cases in the VATS group, no pleural decortication was performed in AVATS group, (p = 0.021). AVATS group was associated with shorter duration time of operation than VATS (22.17 + 6.57 min. Versus 51.93 + 8.85 min., p < 0.001). Length of hospital stay was relatively shorter in AVATS but this was not statistically significant different (p = 0.063). CONCLUSIONS: Our study revealed that uniportal AVATS pleural biopsy has a similar diagnostic efficacy and safety profile with VATS in the diagnosis and treatment of patients with undiagnosed pleural effusion who have a high risk of general anesthesia due to advanced age and comorbidities. Accordingly, uniportal AVATS pleural biopsy may be considered in the diagnosis and treatment of all exudative undiagnosed pleural effusions.

Polyphenol Extract from Evening Primrose (Oenothera paradoxa) Inhibits Invasion Properties of Human Malignant Pleural Mesothelioma Cells.

Extracts from the defatted evening primrose (Oenothera paradoxa Hudziok) seeds are the source of a range of stable polyphenolic compounds, including ellagic acid, gallic acid, and catechin. Our studies evaluate, for the first time, the influence of evening primrose isopropanol extract (EPE) on malignant pleural mesothelioma (MPM) cells. MPM is rarely diagnosed, its high aggressiveness and frequently noted chemoresistance limit its treatment schemes and it is characterized by low prognostic features. Here, we demonstrate that EPE inhibited MPM growth in a dose-dependent manner in cells with increased invasion properties. Moreover, EPE treatment resulted in cell cycle arrest in the G2/M phase and increased apoptosis in invasive MPM cell lines. Additionally, EPE strongly limited invasion and MMP-7 secretion in MPM cancer cells. Our original data provide evidence about the potential anti-invasive effects of EPE in MPM therapy treatment.

Curcumin as an Anticancer Agent in Malignant Mesothelioma: A Review.

Malignant mesothelioma is an infrequent tumor that initiates from the mesothelial cells lining of body cavities. The great majority of mesotheliomas originate in the pleural cavity, while the remaining cases initiate in the peritoneal cavity, in the pericardial cavity or on the tunica vaginalis. Usually, mesotheliomas grow in a diffuse pattern and tend to enclose and compress the organs in the various body cavities. Mesothelioma incidence is increasing worldwide and still today, the prognosis is very poor, with a reported median survival of approximately one year from presentation. Thus, the development of alternative and more effective therapies is currently an urgent requirement. The aim of this review article was to describe recent findings about the anti-cancer activity of curcumin and some of its derivatives on mesotheliomas. The potential clinical implications of these findings are discussed.

Effectiveness and safety of local anesthetic, semi-flexible pleuroscopy - experience from a peripheral hospital.

If the seemingly less invasive semi-flexible pleuroscopes are combined with strategies of conscious sedation and local anesthesia the pleuroscopy has the potential to reach an increasing number of hospital settings. Local experiences can provide valuable information pertaining to the reproducibility of this technique in different scenarios. We performed a retrospective analysis of the clinical records of all patients that had undergone local anesthetic semi-flexible pleuroscopy in our unit between February 2015 and July 2017. Data on demographics, previous biochemical, cytological and histopathological analysis, procedure details, diagnostic and therapeutic results, complications and mortality were collected from all patients. Statistical analysis was performed using SPSS v23. A total of 30 patients were included. They were mainly male (66.7%), with a median age of 72 years (minimum 19 years, maximum 87 years). All presented with exudative pleural effusions and the exam was performed for diagnostic reasons. Pleural tissue was obtained in all patients and the overall diagnostic accuracy was 93.3%. Malignancy was the chief group of diagnosis (66.7%), followed by pleural tuberculosis (13.3%). The procedure was well tolerated and self-limited subcutaneous emphysema was the only complication registered (13.3%). No deaths were associated with the procedure. Our results globally overlap those of wider series and reinforce the perception that local anesthetic semi-flexible pleuroscopy is a well-tolerated, safe and highly accurate diagnostic and therapeutic tool which has proved to be both feasible and effective in our experience.

Does Sericin, as a Novel Pleurodesis Agent, Have Higher Effectiveness Compared to Talcum Powder, Doxycycline, and Silver Nitrate Pleurodesis?

INTRODUCTION: The usefulness of sericin as pleurodesis agent has previously been described. Present study aims to compare sericin pleurodesis regarding success, effectiveness, tolerability, and side-effects. METHODS: Adult, 12-week-old Wistar-albino rats (n=60), divided to five groups as sericin, talcum-powder, doxycycline, silver-nitrate and control. Agents were administrated through left thoracotomy, rats sacrificed twelve-days after. RESULTS: Highest ratio of collagen fibers was observed in sericin group, and the intensity was higher than talcum-powder group (p<0.05). Compared to silver nitrate, sericin group displayed better mesothelial reaction, and multi-layer mesothelium was also better (p<0.05). Foreign body reaction and emphysema were less frequent in sericin group (p<0.05). The presence of biological tissue in parenchyma was less prominent in sericin group (p<0.05). Foreign body reaction on thoracic wall was less common in sericin group (p<0.05). Presence of biological tissue glue in thoracic wall was less prominent in sericin group (p<0.05). Glomerular degeneration was lower in sericin group compared to the silver nitrate group (p<0.05), and tubular degeneration was less common in sericin group than talcum group (p<0.05). Pericarditis was less common in sericin group compared to the other groups (p<0.05). CONCLUSION: As an intrinsic, natural glue protein, sericin protects the lung parenchyma and tissues, and its glue-like characteristics enable pleurodesis. The success of sericin in pleurodesis was demonstrated in the present study based on investigations of the pleurae. Being cost-effective and better tolerated agent associated with a low potential of side effects, sericin is more effective, less expensive and provides more lung parenchyma protection.

Structural heteropolysaccharides as air-tight sealants of the human pleura.

Pulmonary "air leaks," typically the result of pleural injury caused by lung surgery or chest trauma, result in the accumulation of air in the pleural space (pneumothorax). Air leaks are a major source of morbidity and prolonged hospitalization after pulmonary surgery. Previous work has demonstrated structural heteropolysaccharide (pectin) binding to the mouse pleural glycocalyx. The similar lectin-binding characteristics and ultrastructural features of the human and mouse pleural glycocalyx suggested the potential application of these polymers in humans. To investigate the utility of pectin-based polymers, we developed a simulacrum using freshly obtained human pleura. Pressure-decay leak testing was performed with an inflation maneuver that involved a 3 s ramp to a 3 s plateau pressure; the inflation was completely abrogated after needle perforation of the pleura. Using nonbiologic materials, pressure-decay leak testing demonstrated an exponential decay with a plateau phase in materials with a Young's modulus less than 5. In human pleural testing, the simulacrum was used to test the sealant function of four mixtures of pectin-based polymers. A 50% high-methoxyl pectin and 50% carboxymethylcellulose mixture demonstrated no sealant failures at transpleural pressures of 60 cmH2 O. In contrast, pectin mixtures containing 50% low-methoxyl pectin, 50% amidated low-methoxyl pectins, or 100% carboxymethylcellulose demonstrated frequent sealant failures at transpleural pressures of 40-50 cmH2 O (p < 0.001). Inhibition of sealant adhesion with enzyme treatment, dessication and 4°C cooling suggested an adhesion mechanism dependent upon polysaccharide interpenetration. We conclude that pectin-based heteropolysaccharides are a promising air-tight sealant of human pleural injuries. © 2018 Wiley Periodicals, Inc. J. Biomed. Mater. Res. Part B, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 799-806, 2019.

Multisensor Imaging-From Sample Preparation to Integrated Multimodal Interpretation of LA-ICPMS and MALDI MS Imaging Data.

Laterally resolved chemical analysis (chemical imaging) has increasingly attracted attention in the Life Sciences during the past years. While some developments have provided improvements in lateral resolution and speed of analysis, there is a trend toward the combination of two or more analysis techniques, so-called multisensor imaging, for providing deeper information into the biochemical processes within one sample. In this work, a human malignant pleural mesothelioma sample from a patient treated with cisplatin as a cytostatic agent has been analyzed using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). While LA-ICPMS was able to provide quantitative information on the platinum distribution along with the distribution of other elemental analytes in the tissue sample, MALDI MS could reveal full information on lipid distributions, as both modes of polarity, negative and positive, were used for measurements. Tandem MS experiments verified the occurrence of distinct lipid classes. All imaging analyses were performed using a lateral resolution of 40 µm, providing information with excellent depth of details. By analyzing the very same tissue section, it was possible to perfectly correlate the obtained analyte distribution information in an evaluation approach comprising LA-ICPMS and MALDI MS data. Correlations between platinum, phosphorus, and lipid distributions were found by the use of advanced statistics. The present proof-of-principle study demonstrates the benefit of data combination for outcomes beyond one method imaging modality and highlights the value of advanced chemical imaging in the Life Sciences.

Abrupt hemodynamic changes accompanying intrapleural hyperthermic chemotherapy: Case series.

RATIONALE: Intrapleural hyperthermic chemotherapy (IPHC) is the preferred method to locally treat lung cancer with pleural seeding. Anesthetic management during IPHC is a very challenging task for the anesthesiologist because of the hemodynamic instability associated with the procedure; however, there is no report on anesthetic considerations during the IPHC procedure. PATIENT CONCERNS: Three patients who diagnosed lung cancer with pleural invasion scheduled for IPHC were reported in this case series. DIAGNOSIS: Case 1, a 48-year-old woman, suffered from lung cancer (adenocarcinoma, T2NxM1a) with diffuse pleural seeding. Case 2, a 58-year-old female, diagnosed with lung cancer (adenocarcinoma, T3N0M1a) with pleural dissemination. Case 3, a 47-year-old male, diagnosed as sarcoma on the left lung with right pericardial invasion and right hemidiaphragm invasion (stage, T3N0M1a). INTERVENTION: All three patients underwent IPHC with cisplatin diluted in normal saline (2000 ml) at a rate of 600 ml/min. Inflow temperature of 42°C was using a heart-lung machine over 90 minutes. Hemodynamic changes were monitored through the procedure. OUTCOMES: The patient did not require supplemental oxygenation anymore after he recovered from lung transplantation. LESSONS: There was sudden drop in the cardiac output and an increase in the pulmonary vascular resistance, which were caused by the volume and temperature of the hyperthermic chemotherapeutic drugs in the pleura during the early stage of IPHC; these changes can be a major problem during the procedure, and supportive hemodynamic management may be needed.

Dose dependency of outcomes of intrapleural fibrinolytic therapy in new rabbit empyema models.

The incidence of empyema (EMP) is increasing worldwide; EMP generally occurs with pleural loculation and impaired drainage is often treated with intrapleural fibrinolytic therapy (IPFT) or surgery. A number of IPFT options are used clinically with empiric dosing and variable outcomes in adults. To evaluate mechanisms governing intrapleural fibrinolysis and disease outcomes, models of Pasteurella multocida and Streptococcus pneumoniae were generated in rabbits and the animals were treated with either human tissue (tPA) plasminogen activator or prourokinase (scuPA). Rabbit EMP was characterized by the development of pleural adhesions detectable by chest ultrasonography and fibrinous coating of the pleura. Similar to human EMP, rabbits with EMP accumulated sizable, 20- to 40-ml fibrinopurulent pleural effusions associated with extensive intrapleural organization, significantly increased pleural thickness, suppression of fibrinolytic and plasminogen-activating activities, and accumulation of high levels of plasminogen activator inhibitor 1, plasminogen, and extracellular DNA. IPFT with tPA (0.145 mg/kg) or scuPA (0.5 mg/kg) was ineffective in rabbit EMP (n = 9 and 3 for P. multocida and S. pneumoniae, respectively); 2 mg/kg tPA or scuPA IPFT (n = 5) effectively cleared S. pneumoniae-induced EMP collections in 24 h with no bleeding observed. Although intrapleural fibrinolytic activity for up to 40 min after IPFT was similar for effective and ineffective doses of fibrinolysin, it was lower for tPA than for scuPA treatments. These results demonstrate similarities between rabbit and human EMP, the importance of pleural fluid PAI-1 activity, and levels of plasminogen in the regulation of intrapleural fibrinolysis and illustrate the dose dependency of IPFT outcomes in EMP.

The effects of aqueous extract of babassu (Orbignya phalerata) on the pleura and lung parenchyma in rats.

PURPOSE: To evaluate macro and microscopically, changes following the use of the aqueous extract of babassu (Orbignya phalerata) in the lung parenchyma and pleura of rats. METHODS: Sixty adult male rats with average weight of 350 g, were randomized into two groups of 30 animals (experimental and control) further divided into sub-groups of 10 to be sacrificed at 48 h, 72 h and 21 days. The substance was injected into the right pleura of the animals. RESULTS: There was intense pleuropulmonary macroscopic reaction with statistically significant differences between groups respectively (p<0.05, p<0.02, p<0.03). Microscopically, no statistically significant difference was evident (p>0.05). CONCLUSION: The aqueous extract of babassu (Orbignya phalerata) was found to be highly irritating to the pleura and lung of rats, evidenced macroscopically by numerous adhesions and inflammation while no major changes were evident microscopically.

The effects of aqueous extract of babassu (Orbignya phalerata) on the pleura and lung parenchyma in rats

PURPOSE: To evaluate macro and microscopically, changes following the use of the aqueous extract of babassu (Orbignya phalerata) in the lung parenchyma and pleura of rats. METHODS: Sixty adult male rats with average weight of 350 g, were randomized into two groups of 30 animals (experimental and control) further divided into sub-groups of 10 to be sacrificed at 48 h, 72 h and 21 days. The substance was injected into the right pleura of the animals. RESULTS: There was intense pleuropulmonary macroscopic reaction with statistically significant differences between groups respectively (p<0.05, p<0.02, p<0.03). Microscopically, no statistically significant difference was evident (p>0.05). CONCLUSION: The aqueous extract of babassu (Orbignya phalerata) was found to be highly irritating to the pleura and lung of rats, evidenced macroscopically by numerous adhesions and inflammation while no major changes were evident microscopically.

[Intraoperative chemotherapy after radical pleurectomy or extrapleural pneumonectomy]. / Intraoperative Chemotherapie nach radikaler Pleurektomie oder extrapleuraler Pneumonektomie.

Trimodality treatment including induction and/or adjuvant chemotherapy, surgical resection and in some cases radiotherapy offers a curative intention in selected patients with pleural malignancies (malignant pleural mesothelioma, thymoma with pleural spread). Nevertheless, locoregional tumor recurrence mainly limits the outcome and the quality of life. A few years ago an additional intraoperative chemotherapy perfusion was developed in order to improve local tumor control and prognosis after surgical resection in a multimodality treatment setting. Cytoreductive surgery with the purpose of a macroscopic complete resection could be achieved by radical pleurectomy or extrapleural pneumonectomy. The concept, techniques and perioperative management of this additional treatment option are presented along with a detailed review of the recent literature.

[Diagnosing and expertizing asbestos-induced occupational diseases]. / Diagnostik und Begutachtung asbestbedingter Berufskrankheiten.

Due to latency periods that can last for decades, asbestos-related diseases show 18 years after the enforcement of the prohibition of asbestos application in Germany their highest numbers. In the centre of attention are asbestos-induced pleural fibroses, mesotheliomas, asbestoses, lung and laryngeal cancer. Diagnosing and expertizing these diseases causes difficulties, is hitherto non-uniform and does frequently not correspond to the current medico-scientific expertise. This induced the German Respiratory Society as well as the German Society of Occupational and Environmental Medicine in cooperation with the German Society of Pathology, the German Radiology Society and the German Society of Otorhinolaryngology, Head and Cervical Surgery, to develop the above mentioned guideline during seven meetings moderated by AWMF. The required thorough diagnosis is based on the detailed recording of a qualified occupational history. Since the sole radiological and pathological-anatomical findings cannot sufficiently contribute to the causal relationship the occupational history recorded by a general physician and a specialist is of decisive importance. These physicians have to report suspected occupational diseases and to advise patients on social and medical questions. Frequently, problems occur if the recognition of an occupational disease is neglected due to a supposedly too low exposure or too few ferruginous bodies or low fibre concentrations in lung tissue. The new S2k directive summarizing the current medico-scientific knowledge is for this reason, for diagnoses and expert opinions as well as for the determination of a reduced capacity for work a very important source of information.

[Extended thymectomy and intraoperative-intrapleural perfusion hyperthermo-chemotherapy for stage IVa invasive thymoma with myasthenia gravis].

A 37-year-old woman diagnosed with ocular myasthenia gravis was referred to our department. Chest computed tomography (CT) showed anterior mediastinal tumor and right pleural dissemination. Extended thymectomy and right intraoperative-intrapleural perfusion hyperthermo-chemothrapy (IPHC) were performed. Pathological diagnosis was invasive thymoma type B2 and stage IVa based on Masaoka's classification. The post operative course was uneventful. The patient underwent 4 cycles of adjuvant chemotherapy with doxorubicin, cisplatin, vincristine, and cyclophosphamide (ADOC), and is free from recurrence at 12 months postoperatively.

Volumetry: an alternative to assess therapy response for malignant pleural mesothelioma?

The purpose of our study was to assess robustness of volumetric measurement of malignant pleural mesothelioma (MPM) before and after chemotherapy to modified RECIST (response evaluation criteria in solid tumours) criteria. 30 patients with digitally available chest computed tomography (CT) scans before and after three cycles of chemotherapy were included. Three readers independently assessed tumour response using two different methods: 1) the modified RECIST criteria; and 2) the tumour volumetric approach using dedicated software (Myrian; Intrasense, Paris, France). Inter-rater reliability of unidimensional and volumetric measurements was assessed using intraclass correlation. Tumour response classification for modified RECIST was compared to the volumetric approach applying unidimensional RECIST volumetric equivalent criteria. The determination of unidimensional tumour measurement (RECIST) revealed a low inter-rater reliability (0.55) and a low interobserver agreement for tumour response classification (general κ 0.33). Only 14 patients were classified equally. A high inter-rater reliability (0.99) and interobserver agreement (general κ 0.9) were found for absolute tumour volumes (volumetric measurements). 27 cases were classified equally. The number of cases classified as "stable disease" was higher for the volumetric approach using tumour-equivalent criteria compared to modified RECIST. Volumetric measurement of MPM on CT using Myrian software is a reliable, reproducible and sensitive method to measure tumour volume and, thus, therapy response after induction chemotherapy.

[Cytoreductive surgery and hyperthermic intrathoracic chemotherapy perfusion]. / Zytoreduktive Chirurgie und hypertherme intrathorakale Chemotherapieperfusion.

Recently cytoreductive surgery of primary and secondary pleural tumors has been combined with hyperthermic intrathoracic chemotherapy perfusion (HITHOC) for better local tumor control. In comparison to simple instillation of chemotherapeutic agents into the pleural cavity, the combination of surgical resection of pleural tumors and simultaneous HITHOC seems to be a more effective treatment. Intra-operative perfusion allows an improved distribution of the drug in the pleural space and a higher local concentration of the chemotherapeutic agents in contrast to systemic chemotherapy. Additional advantages of HITHOC are a better response to chemotherapeutic agents and synergistic antineoplastic effects. A prerequisite for safe application of HITHOC is compliance with safety regulations. Due to the reduction in morbidity and mortality this new concept is a valuable alternative for selected patients who do not undergo radical resection (e.g. extrapleural pneumonectomy). HITHOC is an additional therapeutic option in the multimodal treatment of patients with primary or secondary tumors of the pleura.

[A case of pulmonary carcinosarcoma with pleural effusion, progressive pleural thickening and a calcification-like lesion].

A 70-year-old man was admitted to our hospital with dyspnea. Chest X-ray film revealed right pleural effusion. Chest CT showed right pleural effusion with slight pleural thickening and a patchy calcification-like lesion. Adenocarcinoma cells were detected in pleural effusion, but upper gastrointestinal endoscopy, barium enema examination and ultrasonography of the abdomen failed to show the primary lesion. We made a diagnosis of primary adenocarcinoma of the lung. Chemotherapy was performed after pleurodesis. However there was gradual increase of right pleural thickening and expansion of the calcification-like lesions. The patient died 16 months after his first visit. Pathological findings of the autopsy specimen revealed the tumor composed of an adenocarcinomatous component and an osteosarcomatous component. The final diagnosis was primary carcinosarcoma of the lung.

Pleural MALT lymphoma diagnosed on thoracoscopic resection under local anesthesia using an insulation-tipped diathermic knife.

A 79-year-old man presented with back pain. Chest CT scan showed elevated nodular lesions in the right parietal pleurae with pleural effusion. There were no intrapulmonary or mediastinal abnormalities. Under local anesthesia, right thoracoscopy and subsequent thoracoscopic pleural resection were performed using an insulation-tipped diathermic knife (IT-knife). The resected pleura, 2.2 cm in diameter, had a rough granular surface. Lymphoid cells histologically infiltrated diffusely into the pleura. They were composed of centrocyte-like and monocytoid cells. On immunohistochemistry they were found to be positive for Bcl2, CD20, CD45RB and CD79a, but negative for CD3, CD5, CD10 and cyclin D1. EBV-encoded small RNA-1 (EBER-1) in situ hybridization was negative. A diagnosis of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) arising in the pleura was therefore made. To the authors' knowledge this is the first case in which IT-knife was used for diagnosis of a pleural lesion. This large, single-piece, only slightly crushed pleural specimen, enabled study of histopathological findings (listed here) that could not have been obtained on conventional biopsy: (i) lack of apparent evidence of plasmacytic differentiation; (ii) no recognition of lymphoid follicles; (iii) mesothelial cells not infiltrated by lymphoma cell clusters; (iv) thin layer of hyperplastic mesothelial cells continuously covering the surface; and (v) no proliferation of fibroblast-like submesothelial cells.