Malignant mesothelioma of the tunica vaginalis testis: report of first case with preoperative diagnosis

Asbestos exposure and malignant mesothelioma of the tunica vaginalis testis: a systematic review and the experience of the Apulia (southern Italy) mesothelioma register

BACKGROUND

Malignant mesothelioma of the tunica vaginalis testis (MMTVT) is a rare disease with a poor prognosis. The diagnosis and management of these lesions are often difficult for pathologists, surgeons, oncologists and occupational physicians. A preoperative diagnosis of malignancy is rarely made, and there is no established effective therapy except orchidectomy.

METHODS

A systematic literature review was conducted among the articles published in the English literature on primary MMTVT. Moreover four cases from the Apulia mesothelioma register are reported here.

RESULTS

Two hundred eighty-nine cases of MMTVT have been reported from 1943 to 2018. Overall asbestos exposure has been investigated only for 58% of all cases reported in this review, while in 41.8% this data are not available. Noteworthy is the fact that in many reports there is not an anamnestic reconstruction of any asbestos exposure. A history of direct occupational, environmental or familial asbestos exposure is found in 27.6% of the cases. The four cases from the Apulia mesothelioma register are all with ascertained occupational exposure to asbestos.

CONCLUSIONS

The true incidence of asbestos exposure in MMTVT is underestimated because of insufficient information reported in older literature. To establish a broad consensus on the causal relationship between asbestos and MMTVT in the scientific community its necessary to analyze the same variables in the epidemiological studies. In general it should be recommended that a positive history of exposure to asbestos or to asbestos-containing materials are at risk for the development of a MMTVT and should be monitored.

Cytopathological Diagnosis of an Unusual Cause of Malignant Hydrocele

Testicular involvement in a case of acute lymphoblastic leukemia (ALL) is well reported, but occurrence of “isolated” malignant hydrocele is extremely uncommon. We herein report a case of a 22-year-old man who presented to our hematology clinic with fever and easy fatiguability of 2 weeks’ duration. Examination revealed pallor, cervical lymphadenopathy, and bilateral scrotal swellings. He was diagnosed as a case of Philadelphia-positive ALL (B-cell type) based on peripheral smear, bone marrow examination, and flow cytometry of the marrow aspirate. Ultrasonography of scrotum revealed bilateral hydrocele with normal testes. Cytopathological analysis of the hydrocele fluid showed the presence of lymphoblasts. The patient was treated with modified BFM-90 protocol along with imatinib mesylate (600 mg/day). He achieved complete remission with a minimal residual disease of <0.001% at the end of induction therapy. However, the hydrocele persisted and a repeat cytological examination of the aspirate did not reveal any lymphoblasts. The patient was treated with consolidation (high-dose methotrexate), bilateral testicular irradiation, and re-induction following which the hydrocele disappeared. The patient is currently on maintenance phase of BFM-90 protocol and is alive at one year of follow-up. Contiguous spread from the subclinical testicular involvement is hypothesized as the mechanism for development of hydrocele in the current case. The role of cytopathology in the early diagnosis of testicular involvement in ALL is emphasized here.

Preoperative cytological diagnosis of malignant mesothelioma of tunica vaginalis

Malignant mesothelioma of tunica vaginalis testis is a rare aggressive neoplasm with ∼200 cases reported so far. A correct preoperative diagnosis of this rare tumor is difficult. Fine-needle aspiration cytology (FNAC) is a rapid and inexpensive diagnostic tool that may prove helpful in such cases. Very few cases have been diagnosed on cytology so far, and the descriptions of the cytological features have rarely been described in the literature. In this report we present the cytological features of malignant mesothelioma of tunica vaginalis testis which was diagnosed by FNAC and subsequently confirmed by histopatholoy and immunohistochemical (IHC) studies.

Perineal and colonic metastases in two cases of malignant mesothelioma

Two patients with rare sites of metastatic pleural mesothelioma are presented and the literature on similar cases is examined. One patient developed colonic metastases from a sarcomatoid mesothelioma. Another patient with epithelioid mesothelioma developed perineal metastases.

Mesothelioma of tunica vaginalis testis and asbestos exposure

Study Type - Therapy (case series). Level of Evidence 4. What's known on the subject? and What does the study add? Mesothelioma of the tunica vaginalis testis is a rare tumour. From 2000 to 2010, 13 mesothelioma of the tunica vaginalis testis cases were reported in the most populated and industrialized region in Italy. Asbestos exposure was documented in two-thirds of these cases.

OBJECTIVE

• To describe cases of mesothelioma of the tunica vaginalis testis (MTVT) recorded in the Lombardy Mesothelioma Registry between 2000 and 2010.

METHODS

• The Lombardy Mesothelioma Registry, established in 2000, collects data regarding all incident cases of mesothelioma of the pleura, peritoneum, pericardium and tunica vaginalis testis that have been diagnosed in the population of the Lombardy region. • These data include a detailed clinical report and a complete occupational history for each MTVT patient, with the latter including details of the industrial sector involved, the patient's job, and the specific tasks performed. To address the potential for asbestos exposure outside the work environment, the residential history, lifestyle habits and hobbies of the patient, as well as job information for all subjects living with the patient, are also collected. • Records were reviewed and discussed by a panel of experts.

RESULTS

• Thirteen cases of MTVT were reported between 2000 and 2010. • The age-standardized incidence rate of MTVT for the Lombardy region of Italy is 0.2 cases per million individuals/year. • Asbestos exposure was documented in 8 of the 12 (67%) interviewed cases.

CONCLUSIONS

• Asbestos exposure was associated with a higher proportion of MTVT cases than previously reported in the literature. These results confirm the aetiological role for asbestos in the pathogenesis of MTVT. • The results of this study also highlight the importance of obtaining detailed occupational histories and lifestyle habits from patients, particularly by trained interviewers.

Hydroceles: Disturbing Discoveries During Routine Repair

Hydroceles are a common presenting complaint to the urological surgeon. They are known to harbour malignancy in a small percentage of cases. We report a case of malignant mesothelioma of the tunica vaginalis and a case of isolated lymphoma of the spermatic cord, both presenting during routine hydrocele repair. These are both rare diagnoses with a handful of reported cases worldwide. The literature of both these pathological entities is reviewed.

[Malignant mesothelioma of the tunica vaginalis]

Case report of a new case of malignant mesothelioma of the tunica vaginalis testis. A mediterranean male age 62, presented with enlargement and swelling of the scrotum, treated as orchiepydidymitis within the previous 3 months. Physical and ultrasonography examination showed a left scrotal mass with extension to the skin of the scrotum. After surgery (orchiectomy and partial hemiscrotectomy) and histopathology diagnosis of locally advanced malignant mesothelioma, CT showed metastasis in retroperitoneum, Lung and Liver. The patient undergoes chemotherapy and radiotheraphy with a poor prognose. We review the diagnosis, histopathology and therapeutical approach for this uncommon kind of paratesticular tumor (less than 80 cases reported in the last 30 years).

Malignant mesothelioma of the tunica vaginalis testis: report of a case

We describe herein the case of a 68-year-old man with malignant mesothelioma of the tunica vaginalis testis. The pathological diagnosis was based upon the clinical findings, gross and microscopic morphology, and special stains. Malignant mesothelioma is a rare tumor associated with asbestos exposure that can be effectively treated with orchidectomy via an inguinal approach.

Malignant mesothelioma of the tunica vaginalis testis: a report of two cases and review of literature

Two cases of rare malignant mesothelioma of tunica vaginalis testis are presented. Both cases were advanced on clinical and radiological studies. One patient was treated with surgical excision followed by chemotherapy and radiotherapy and the other patient was treated with surgery and chemotherapy. Despite aggressive therapy both the patients died within 18 months of treatment. Review of the literature with suggested treatment protocol is presented. The response of malignant mesothelioma to chemotherapy and radiotherapy is poor as indicated by both of our cases. Initial aggressive surgery and adjuvant procedures are necessary soon after diagnosis to achieve long-term survival.

Malignant mesothelioma of the tunica vaginalis testis: review of the literature and assessment of prognostic parameters

BACKGROUND

Only 73 cases of malignant mesothelioma of the tunica vaginalis testis have been reported in the last 30 years. Although these tumors were most often seen in patients between ages 55 and 75 years, 10% of the patients were younger than 25 years. Because prognostic parameters have not yet been reported, the authors present another case of a male age 14 years and a review of the available literature, which they conducted to determine prognostic parameters.

METHODS

The medical literature about malignant mesothelioma of the tunica vaginalis testis was reviewed. For the determination of prognostic parameters, a univariate and multivariate Cox regression model was used to assess the relevance of the patient's age, history of asbestos exposure, tumor histology, primary therapeutic approach, and presence of metastatic disease to survival.

RESULTS

Previous exposure to asbestos or asbestos-containing materials must be considered a risk factor for the development of malignant mesothelioma. The major difficulty in managing patients with malignant mesothelioma of the tunica vaginalis testis was determining an accurate preoperative diagnosis, which was reported in only two cases. Due to the lack of characteristic symptoms, 97.3% of the cases were diagnosed intraoperatively. Of patients who underwent local resection of the hydrocele wall, 35.7% experienced local tumor recurrence, as compared with 10.5% after scrotal orchiectomy and 11.5% after inguinal orchiectomy. Therefore, radical orchiectomy should be the first-line therapy. The median survival of the patients was 23 months, which decreased to 14 months in cases of recurrence. The overall recurrence rate (local and disseminated) was 52.5%. More than 60% of recurrences developed within the first 2 years of the follow-up. In some cases of disseminated mesothelioma, adjuvant chemotherapy or radiotherapy was given. Although reports on adjuvant treatments were limited, radiotherapy appeared to be more effective than chemotherapy. However, 37.9% died of disease progression. Assessment of prognostic parameters revealed a significant correlation of patient's age with survival (P < 0.01), with a better outcome for younger patients and a worse disease course for patients with primary disseminated disease (P < 0.05) in univariate analysis. A multivariate Cox regression model of prognostic parameters concerning survival did not yield statistically significant results.

CONCLUSIONS

Malignant mesotheliomas of the tunica vaginalis testis rarely occur, but the possibility should be considered for all age groups. Univariate analysis determined that a patient's age and the presence of primary disseminated disease were prognostic parameters related to survival. Due to the invasive potential of this disease and the risk of tumor recurrence, radical orchiectomy and close follow-up are strongly recommended.

Pre-operative diagnosis of malignant mesothelioma of tunica vaginalis testis by hydrocele fluid cytology

Malignant mesothelioma of tunica vaginalis testis is a rare tumour usually associated with hydrocele. Until now only one case has been documented, where a pre-operative diagnosis was made by cytological examination of hydrocele fluid. We report one more case with pre-operative diagnosis using hydrocele fluid cytology.

Primary malignant mesothelioma of the tunica vaginalis of the testis. Immunohistochemistry and electron microscopy

A case of primary malignant mesothelioma of the tunica vaginalis of the testis in a 75 year old man is here presented. Anamnesis for asbestos exposure was negative. Recurrent left hydrocele was the main symptom. Echography revealed a nodular mass in the caudal aspect of the epididymis and papillary projection on the surface of the tunica vaginalis of the testis. An inguinal left orchiectomy was performed. The tumor both in the solid area and in the papillary projections was identified as a malignant mesothelioma of epithelial type. The role of immunohistochemistry and ultrastructure for a correct definition of the tumor is underlined.

Hypericin in phototherapy

We describe the first local use of hypericin as photosensitizer for photodynamic therapy in a patient with recurrent malignant mesothelioma. Hypericin is a polycyclic quinone, which has been shown to possess in vivo and in vitro antiretroviral and photosensitizing activity; moreover, it is used in depressive disorders. The semiquinone radical, singlet oxygen, and superoxide anion radical are reported to be the toxic agents in hypericin phototherapy. Our first experience with locally applied hypericin in a superficial tumor-plate was performed 8 weeks after the systemic administration of hematoporphyrin derivatives. For tumor light illumination we used an argon pumped dye laser tuned to 632 nm. Owing to satisfactory results, we repeated the same therapy 4 weeks later- and no therapeutic effect was noted. Following this, we proved the interstitial application of HPD and the combination of interstitial HDP and superficially applied hypericin. The subsequent light illumination 6 hours later had no efficacy in the HDP-photosensitized area but there was tumor destruction in the field with both administered photosensitizers. Our first experience suggests a potentiation of two photosensitizers: hematoporphyrin derivatives and hypericin.

Concomitant malignant mesothelioma of the pleura, peritoneum, and tunica vaginalis testis

We describe the cytohistological, immunohistochemical and ultrastructural findings in a 55-yr-old-man with history of asbestos exposure and diffuse malignant mesothelioma (DMM) of the pleura, peritoneum, and tunica vaginalis presenting with chest pain and scrotal swelling. Pleural fine-needle aspiration (FNA) revealed mesenchymal elements and spindle-shaped epithelial-like cells, while biopsy showed pure sarcomatous tumor invading lung parenchymal. In both samples tumor cells coexpressed cytokeratin and vimentin. Peritoneal and hydrocele effusions contained aggregates of malignant mesothelial cells. Electron microscopy showed intermediate filaments, rare desmosomes and sparse microvilli. Morphological findings were consistent with a DMM, with a biphasic pattern in the pleura and an epithelial one in the peritoneum and tunica vaginalis. Although the possibility of a multicentric origin cannot be ruled out, clinical chronologic sequence suggests that the pleura was the primary involved site, followed by spread to peritoneum and tunica vaginalis.

Malignant mesothelioma of the tunica vaginalis testis diagnosed by aspiration cytology--a case report with review of literature

A case of malignant mesothelioma of the tunica vaginalis testis diagnosed by preoperative cytology of hydrocele fluid is reported. In our view this is only the second case diagnosed by preoperative cytology. The unique feature of this case, the characteristic ultrasound appearance, was recognized and confirmation by aspiration cytology led directly to radical orchiectomy, thus avoiding hydrocelectomy, hemiscrotectomy and possible local recurrence. Aetiopathogenesis and management options of this rare tumour are discussed, with a review of the literature.

Case report: malignant mesothelioma of the tunica vaginalis testis--an indolent course

Malignant mesothelioma of the tunica vaginalis testis is an extremely rare tumour. So far less than 50 cases have been reported in the literature. Radical inguinal orchiectomy appears to be the optimal treatment. Upon recurrence, treatment remains unsatisfactory. A further case is reported here, where the disease ran an indolent course despite several recurrences after initial treatment.

Combined therapy in a case of malignant mesothelioma of the tunica vaginalis testis

Malignant mesothelioma of the tunica vaginalis testis is exceedingly rare. A new case mimicking hydrocele in a 47-year-old man is here reported. Clinical staging revealed scrotal cutaneous and funicular tumor invasion together with retroperitoneal adenopathies. Once visceral dissemination was ruled out, radical orchiectomy, left hemiscrotectomy and modified retroperitoneal lymph node dissection were performed. Adjuvant systemic chemotherapy and radiation were also administered. Histologically, an epithelial neoplasm with papillary pattern was evidenced. CAM 5.2 cytokeratin was positive in proliferating cells, but carcinoembryonic and Leu M1 antigens gave negative results. Three years later the patient is free of disease.

Biochemical analysis of tunica vaginalis fluid in patients with or without idiopathic hydroceles

OBJECTIVE

To establish the differences, if any, between the biochemical composition of idiopathic hydrocele fluid and the fluid normally present in the tunica vaginalis.

PATIENTS AND METHODS

Aspiration and sclerotherapy of 37 idiopathic hydroceles from patients who presented to this urology clinic were performed. The biochemical content of the fluid was compared with that of the tunica vaginalis fluid from a small group of controls (n = 8), taken from patients undergoing orchidectomy for carcinoma of the prostate.

RESULTS

Differences in several measurements were recorded; in particular, there were significantly higher concentrations of calcium, albumin, total protein and creatine-kinase in the hydrocele group. The levels of potassium, aspartate transaminase, alanine transaminase and alkaline phosphatase were significantly lower in the hydrocele group.

CONCLUSION

Whether these differences have a role in the causation of an idiopathic hydrocele is, at this stage, speculative. A similar study on a larger scale would probably be more conclusive.

A new case of malignant mesothelioma of the tunica vaginalis testis. Immunohistochemistry in comparison with an adenomatoid tumor of the testis

Malignant mesothelioma of the tunica vaginalis testis is an extremely rare tumor with 41 previously reported cases. The histological and immunohistological features of a new case in an 80-year-old patient are described and compared with an adenomatoid tumor of the tunica vaginalis testis, which is considered to be the benign variant of malignant mesothelioma. Both tumors revealed strong cytoplasmic staining for a panepithelial antibody (Lu-5) and membranous staining for BMA-120 (a mesothelial/endothelial cell marker) but yielded negative staining results with the endothelial cell markers QBend-10 (CD 34), Factor VIII-related antigen (vWF) and UEA-1. There was also negative staining for CEA, Ber-EP4, HEA-125 and Blood group related antigens A, B, H. An identical staining pattern was evident in normal and reactive mesothelial cells. Our data support a mesothelial rather than an endothelial derivation of the adenomatoid tumor studied.

Case report: ultrasound appearances of a malignant mesothelioma of the tunica vaginalis testis

A case of a 91-year-old gentleman who developed massive scrotal swelling secondary to malignant mesothelioma of the tunica vaginalis testis is presented. Preoperative sonography was performed and the findings and difficulty in establishing the pathological diagnosis are discussed.

Malignant mesothelioma of the tunica vaginalis testis. Report of a case and review of the literature

An autopsy case of malignant mesothelioma of the tunica vaginalis testis in a 60-year-old man is described. The tumor showed widespread metastasis via the lymphatics, leading to the patient's death five years after diagnosis. A review of 38 previously described cases is also presented. The most frequent presenting symptom was hydrocele. When a hydrocele in association with a paratesticular tumor is present, aspiration cytology should be performed first. In most of the cases with a fatal outcome, the tumors metastasized to the retroperitoneal lymph nodes. Once the diagnosis has been made, lymphangiography or CT scan should be done immediately.

Background incidence of mesothelioma: animal and human evidence

Evidence is presented showing that mesotheliomas can have causes other than exposure to asbestos dust, in both experimental animals and humans. In experimental animals, for example, results from two major experimental laboratories suggest that at least 10% may be taken for background incidence, whereas a third laboratory suggests that the experimental group must have a rate exceeding 30% "Background" also includes mesotheliomas found in association with nonfibrous and fibrous nonasbestiform agents. Mesotheliomas in humans can be broadly classified in a manner similar to those of experimental animals: (1) spontaneously occurring, (2) those with a latent period less than 10 years, (3) childhood mesotheliomas, (4) familial cases, (5) cases before the 20th century, (6) mineralogically negative mesotheliomas, and (7) mesotheliomas caused by nonasbestiform agents. The importance of the acceptance of these "background" cases lies in the fact that a basis is provided for the study of the incidence of disease associated with various types of asbestos.

Malignant mesothelioma of the tunica vaginalis testis

Malignant mesothelioma of the tunica vaginalis is an extremely rare tumor. Appropriate treatment consists of inquinal orchiectomy with close followup. Treatment of locally recurrent malignant mesothelioma of the tunica vaginalis has not been standardized. We recommend radical resection for the initial presentation of locally recurrent disease rather than saving surgical resection as salvage therapy after other treatment modalities have failed. We report case 37 of malignant mesothelioma of the tunica vaginalis and review the literature.

Retroperitoneal lymph node dissection in malignant mesothelioma of tunica vaginalis testis

A case of metastatic mesothelioma of the tunica vaginalis testis in a 57-year-old man is reported. Clinicopathological findings and treatment options are reviewed.

Malignant mesothelioma of the tunica vaginalis

A case of a malignant mesothelioma of the tunica vaginalis is presented. The patient with an intrascrotal mass was a 32-year-old Japanese male who had no history of asbestos exposure. The tumor was located on the surface of the right testis and was composed of columnar to polygonal cells with glandular and papillary structures. It showed many mitoses and focal invasion of the tunica albuginea. The tumor cells contained alcian blue- and Hale's colloidal iron-positive, hyaluronidase-digestible materials. Immunohistochemical stains for cytokeratin and vimentin were positive, while those for carcinoembryonic antigen, epithelial membrane antigen, Leu-M1, and factor VIII-related antigen were negative. The systemic examinations revealed no other tumors. Based on these findings the tumor was diagnosed as malignant mesothelioma of the tunica vaginalis. The differential diagnosis is discussed under the histologic, histochemical, and immunohistochemical points of view and the previous literature is reviewed.

Aspiration cytology of palpable lesions of the scrotal content

To date, we have studied 89 palpable lesions of the scrotum, testicle, and epididymis using fine-needle aspiration cytology (FNAC). Cystic lesions (48.3%) and inflammatory pathology (25.8%) were the most frequent findings. Tumors accounted for 11.2% of results, with a slight predominance of the malignant varieties. In this article, we describe the cytopathology of the main entities and discuss the principal problems of differential diagnosis, especially among inflammatory processes, seminomas, and embryonal carcinomas. The cytopathological pattern of the neoplasias is highly characteristic, and this permits their diagnosis with great precision. FNAC is essentially nontraumatic and easy to carry out, but it requires considerable practice in its execution and in the interpretation of the aspirates. We believe FNAC to be the technique of choice for the study of the pathology of the scrotal content, and we think that it should be employed on the patient's very first visit. The main advantage of FNAC is avoiding delays in diagnosis.

Malignant mesothelioma of tunica vaginalis testis

Malignant mesothelioma of the tunica vaginalis is rare, but sometimes curable. It is similar to malignant mesothelioma of the peritoneum and of the pleura, and is likewise associated with asbestos exposure. We report a case, with correlative computed tomography, ultrasound, and gross pathology images that demonstrate tiny tumor implants studding the vaginalis testis. The literature is reviewed.

Aspiration biopsy cytology of mesothelioma

From 1977 to 1986, 39 cases at our institution were diagnosed as "consistent with mesothelioma" by percutaneous fine-needle aspiration biopsy. All were verified clinically and/or histologically, with no false-positive results. All mesotheliomas except four tumors of peritoneal origin originated from the pleura. On the basis of their cytomorphologic features in correlation with histopathology, the tumors were classified into four types: benign, carcinomatous, sarcomatous, and undifferentiated. Of these 39 cases of mesothelioma diagnosed by aspiration biopsy, nine were benign type; 14, carcinomatous type; 13, sarcomatous type; and three, undifferentiated type. The cytomorphologic features and patterns of different types of mesotheliomas observed in aspirate preparations are presented, and the differential diagnosis is discussed. It appears feasible to investigate pleural- or peritoneal-based lesions with fine-needle aspiration biopsy, particularly in patients without effusions or with negative results in effusion examinations. It is also possible to make a definitive diagnosis of mesothelioma on the basis of cytologic findings coupled with special and immunoperoxidase staining in combination with roentgenographic findings and clinical history.

Mesotheliomas of the tunica vaginalis testis and hernial sacs

Three histologically and immunohistochemically well-documented cases of mesothelioma of the tunica vaginalis testis and hernial sac are presented. Analysis and follow-up data on our three patients and a review of 30 previously reported cases have revealed a varied and often unpredictable clinical course. A classification into high- and lowgrade malignant tumours is suggested, based on clinical and pathological findings.

Malignant mesothelioma of the tunica vaginalis testis: a case report

We report a case of malignant mesothelioma of the testicular tunica vaginalis. A preceding hydrocele showed mesothelial hyperplasia of its lining. The tumor was treated surgically as well as with a combination of radiotherapy and chemotherapy but it progressed, resulting in death within 21 months from the diagnosis. The relationship of the tumor to mesothelial hyperplasia and to previous exposure to asbestos is discussed.

Malignant papillary mesothelioma of the tunica vaginalis testes: cutaneous metastases showing pagetoid epidermal invasion

Malignant papillary mesothelioma of the tunica vaginalis testis is an extremely rare tumor arising from the mesothelium of the tunica vaginalis. A total of 14 cases have been reported, with only two exhibiting cutaneous metastases. We present a third case of cutaneous metastases arising from this unusual tumor. In addition, this is the first reported case of the occurrence of pagetoid epidermal invasion in this condition.

Nodular fibrous proliferation (fibrous pseudotumour) of the tunica vaginalis testis. A light, electron microscopic and immunocytochemical study of a case and review of the literature

A case of nodular fibrous proliferation of the tunica vaginalis testis occurring in a 25-year-old male is described. Electron microscopy and immunocytochemical analysis confirm a fibroblastic origin. The histogenesis of the lesion is considered in the light of the findings and a review of the literature. It is concluded that the lesions known variously as 'fibrous pseudotumour' and 'reactive periorchitis' represent a fibroblastic overgrowth of the genito-urinary tract in response to trauma or infection. Nodular or diffuse fibrous proliferation of the testicular tunica vaginalis is suggested as a unifying terminology for this group of lesions.

Flow cytometric identification of cancer cells in effusions with Ca1 monoclonal antibody

The fluorescence of cells from 42 pleural and peritoneal effusions stained with Ca1 monoclonal antibody (Ca1MA) was studied by flow cytometry. In 14 of 17 malignant effusions a significantly higher intensity of fluorescence was observed in samples exposed to Ca1MA when compared with controls. There was no increase of fluorescence intensity in 25 benign effusions. The method failed in three malignant effusions: one due to endometrial carcinoma and two to malignant lymphoma. The sensitivity of the method was tested in experimental samples with a known percentage of malignant cells. The positive fluorescence with Ca1MA was detected in samples containing 0.1% of carcinoma cells. Flow cytometry with Ca1MA can be a relatively simple method of identification of malignant cells in effusions.

Immunoperoxidase study on adenomatoid tumor of the epididymis using anti-mesothelial cell serum

The mesothelial origin of epididymal adenomatoid tumor is supported by the current study for the presence of mesothelial antigen in the tumor cells. By an indirect immunoperoxidase technique, anti-mesothelial cell serum showed positive cytoplasmic staining in five of the six adenomatoid tumors studied. Previous findings of the presence of strong cytoplasmic keratin and the absence of carcinoembryonic antigen and Factor VIII-related antigen in these tumor cells are also confirmed by this study.

Biphasic malignant mesothelioma (malignant adenomatoid tumor) of paratesticular tissue

This article describes a metastasizing tumor of the paratesticular tissue which has features similar to that of malignant mesothelioma commonly seen in other mesothelial surfaces. The tumor is composed of two types of cells, epithelial-like and spindle-shaped malignant cells.

Occluding junctions in an epithelioid mesothelioma: a freeze-fracture study

The presence of a well-developed tight junction system in a case of diffuse, papillary, malignant mesothelioma of the peritoneum is documented using the freeze-fracture methodology. The mean number of strands within the tight junction network was determined to be 3.83 +/- 0.16. In addition, the tight junctions were specifically located in regions of the plasma membrane adjacent to recognizable microvilli. Gap junctions and desmosomes were found in close association with the occluding complexes; however, they were also seen in areas of the plasma membrane quite distinct from those that exhibit tight junction differentiation. The possible significance of the presence of tight junctions in neoplastic epithelial cells is also discussed.