Benign multicystic peritoneal mesothelioma mimicking mucinous ovarian neoplasm with pseudomyxoma peritonei.

Cystic mesothelioma, also known as benign multicystic peritoneal mesothelioma (BMPM), is a rare neoplasm and one of the five main histological types of peritoneal mesothelioma. Although it is usually considered benign histologically, it is increasingly accepted as a 'borderline malignancy' because the local recurrence rate is high. It is more common in middle-aged women and is generally asymptomatic. Considering that BMPM is often found in the pelvis, it is difficult to differentiate from other pelvic and abdominal lesions, such as cystic ovarian masses, especially mucinous cystadenoma-adenocarcinoma, pseudomyxoma peritonei, etc. Preoperative diagnosis is very difficult due to its rarity and lack of specific diagnostic imaging and clinical findings. Definitive diagnosis is made only by pathological evaluation. In this article, we aimed to present the imaging findings of a BMPM case in a woman who was diagnosed with mucinous ovarian neoplasm with pseudomyxoma peritonei preoperatively and underwent cytoreductive surgery with hyperthermic intraperitoneal chemotherapy.

Thoracic benign cystic mesothelioma.

BACKGROUND: Benign cystic mesotheliomas (BCMs), also known as multilocular mesothelial inclusion cysts, inflammatory inclusion cysts or multicystic mesothelial proliferation, are frequently observed in females and are localised localised in the pelvic peritoneum. They are rarely present in the thoracic and mediastinal areas; however, these locations have been reported in a few cases in the literature. CASE PRESENTATION: We present the case of a woman with an intrathoracic BCM. A 28-year-old female patient presented with a cystic mass of 8 × 6 × 6 cm in the left hemithorax shown by computed tomography of the thorax. The patient underwent cystic mass excision with video-assisted thoracoscopic surgery (VATS), which was completed without complications. The diagnosis was confirmed histopathologically after the surgical resection. CONCLUSIONS: Due to BCMs' non-specific clinical symptoms and radiological imaging, preoperative diagnosis is difficult, and they are often confused with pericardial cysts. There is no standard treatment protocol; however, VATS and en bloc resection are the most frequently used treatment options for mediastinal localization. Since these lesions slow proliferation rates have the potential for local recurrence and low malignant transformation, close follow-up is recommended. In this case report, we aimed to present a rare BCM case with intrathoracic paracardiac localization was completely excised through VATS. No recurrence has been detected in three years of follow-up.

BENIGN MULTICYSTIC PERITONEAL MESOTHELIOMA MIMICKING GYNECOLOGIC PATHOLOGY.

Benign multicystic peritoneal mesothelioma is a rare pathology that arises from the abdominal peritoneum. It has an affinity to develop on the surfaces of pelvic viscera. It predominantly occurs in women of reproductive age. The most used form of treatment is complete surgical removal. We report a case of a a 21-year-old female patient who presented with unclear diffuse abdominal pain. Transvaginal ultrasound and magnetic resonance imaging of the abdomen and pelvis revealed multiple functional cysts in the projection of the right and left ovary and free fluid in the pouch of Douglas. Laparoscopy was performed and multicystic tumor with thin, smooth walls, filled with clear serous content was found in lesser pelvis spreading to the left paracolic region and under the spleen. The multicystic mass was removed. Histologic examination revealed cystic formations filled with mucous content and formed from connective tissue outside and single row epithelium-mesothelium inside. Definitive diagnosis was benign multicystic mesothelioma of the abdominal peritoneum. The patient was well at one year follow-up.

A rare case of benign multicystic peritoneal mesothelioma misdiagnosed as hydatid cyst found in the liver parenchyma and abdomen cavity of a male with asbestos exposure.

BACKGROUND: Benign Multicystic Peritoneal Mesothelioma (BMPM) is one of the rarest diseases in medicine with only more than 200 cases worldwide. This paper aims to report a case of Benign Multicystic Peritoneal Mesothelioma that strangely arose from the liver and was long treated as Hydatid cyst. The case also had many risk factors including asbestos exposure that had not yet been linked with Benign Multicystic Peritoneal Mesothelioma. CASE PRESENTATION: We report a case of a 62 years old male with a history of a perforated peptic ulcer and a cystic mass in the liver that was misdiagnosed as hydatid cyst 7 years ago. He presented with generalized abdominal pain and bloating. Image studies showed many cystic formations filled with clear fluid. An en bloc surgery was performed and a pathologic study showed a multiloculated mass lined by flat or cuboidal epithelium leading to the diagnosis of BMPM. A follow up was scheduled after 3 months revealed total recurrence. CONCLUSION: BMPM resembles many other cystic lesions in the abdomen and should be taken into consideration when dealing with nontypical cystic formations. Its diagnostic and treatment methods are still hazy making this disease difficult to approach.

Quistes mesoteliales benignos con posible origen en las trompas de Falopio resecados por laparotomía / Benign mesothelial cysts with possible origin in the Fallopian tubes resected by laparotomy

Introducción. Los quistes mesoteliales benignos son una entidad poco frecuente, que ocurren especialmente en mujeres en edad reproductiva. Se deben a una proliferación anómala del mesotelio que puede ser originada en varias estructuras intraabdominales e inicialmente es asintomática. Caso clínico. Se presenta el caso de una mujer de 20 años con un cuadro sugestivo de neoplasia maligna, en quien se confirmó el diagnóstico de quiste mesotelial originado en la trompa de Falopio derecha. Se realizó tratamiento quirúrgico exitoso. Discusión. A pesar de la estrecha relación de esta entidad con el útero y los ovarios, no se encuentran reportes de quistes mesoteliales originados a partir de las trompas de Falopio. El tratamiento de los quistes mesoteliales es quirúrgico y en el caso de esta paciente se hizo con la finalidad de mejorar los síntomas y erradicar la enfermedad. Las decisiones fueron tomadas basadas en la opinión de expertos en oncología en una junta de tumores gastrointestinales. Conclusiones. Los quistes mesoteliales son neoplasias de baja incidencia, pero se deben tener en cuenta como diagnóstico diferencial de los tumores abdominales. Se presenta el caso de una paciente tratada de forma quirúrgica con resultados exitosos y seguimiento a un año sin recurrencias

Introduction. Benign mesothelial cysts (BMC) are a rare entity that occurs especially in women of reproductive age. It is due to an abnormal proliferation of the mesothelium that can originate from various intra-abdominal structures and it is initially asymptomatic. Clinical case. This is a case of a 20-year-old woman with a suspicious malignant neoplasia, in whom the diagnosis of a mesothelial cyst originating in the right Fallopian tube was confirmed. Successful surgical treatment was achieved. Discussion. Despite the close relationship of this entity with the uterus and ovaries, there are no reports of me-sothelial cysts originating from the Fallopian tubes. The treatment of mesothelial cysts is surgical and in the case of this patient it was performed in order to improve the symptoms and eradicate the disease. The decisions were taken based on the oncologists' expert opinion of the gastrointestinal tumor board. Conclusions. Mesothelial cysts are neoplasms of low incidence, but they should be considered as a differential diagnosis of abdominal tumors. The case of a patient treated surgically with successful results and a one-year follow-up without recurrences is presented

Benign multicystic peritoneal mesothelioma in a postmenopausal woman complicated with an ovarian cyst: a case report.

Benign multicystic peritoneal mesothelioma is a rare cystic neoplasm, characterized by subtle symptoms, that occurs predominantly in reproductive-aged women. The pathogenesis and etiology of the disease are yet to be determined. We herein present a 71-year-old woman presented to our clinic with persistent low back pain. The clinical examination showed a palpable mass in the abdominal area. The magnetic resonance imaging revealed multiple cystic lesions that occupy the largest part of the pelvis, posterior to the uterus. The patient underwent cyst excision, total hysterectomy with bilateral salpingo-oophorectomy, omentectomy and lymph node dissection. Postoperative course was uneventful and histopathology of the specimen revealed a benign multicystic peritoneal mesothelioma. Complete tumor resection is considered the optimal therapeutic approach of peritoneal mesothelioma. Histopathological analysis is required to confirm the diagnosis of multicystic peritoneal mesothelioma.

Mesotelioma peritoneal multiquístico benigno: reporte de un caso y revisión de la literatura / Benign multicystic peritoneal mesothelioma: case report and literature review

INTRODUCCIÓN: El mesotelioma peritoneal multiquístico benigno (MPMB) es una entidad con muy baja incidencia que se presentan con mayor frecuencia en mujeres jóvenes. CASO CLÍNICO: Paciente de 17 años que consulta por amenorrea secundaria. Además, refería pérdida de peso, estreñimiento y molestias abdominales. La exploración fue normal y en las pruebas de imagen se objetivó una pelvis ocupada por una masa multiquística, de unos 20 cm de diámetro máximo, de paredes finas y contenido anecoico. Se solicitaron marcadores tumorales de los cuales sólo se encontró elevado el CA 19.9 (35,2 U/mL). Se decidió realizar una laparoscopia exploradora para establecer un diagnóstico y ante los hallazgos y al considerarse la masa fácilmente resecable, en el mismo acto quirúrgico se extirpó por completo para su estudio anatomopatológico, que confirmó un MPMB. Se desestimaron tratamientos adicionales y actualmente se encuentra en seguimiento y asintomática. CONCLUSIÓN: La patogénesis del MPMB no está clara. Algunos autores defienden que se trata de una reacción peritoneal a un daño inflamatorio, otros apoyan que se trata de una neoplasia benigna. Esta naturaleza incierta, junto con la escasa experiencia, hacen que el manejo resulte complejo. Es necesario individualizar cada caso e intentar ser conservadores especialmente en pacientes jóvenes. Si se opta por un manejo activo, lo más acertado es la citorreducción completa seguida de quimioterapia hipertérmica peritoneal. El seguimiento, en cualquier caso, debe ser exhaustivo y multidisciplinar principalmente con pruebas de imagen.

BACKGROUND: Benign Multicystic Peritoneal Mesothelioma (BMPM) is an entity with a very low incidence that occurs more frequently in young women. CASE REPORT: A 17-year-old woman attended for secondary amenorrhea. She also referred to weight loss, constipation and abdominal discomfort. The examination was normal and echography revealed a pelvis occupied by a 20 centimeters multicystic mass, with thin walls and anechoic content. A preoperative study with tumor markers was requested in which only a CA 19.9 elevation was observed (35.2 U/ml 0-27). It was decided to perform an exploratory laparoscopy to establish a diagnosis. Due to the findings and because of the fact that the mass was considered easy to remove, it was completely removed in the same surgical act. The pathological result confirmed a BMPM. Additional treatments have been dismissed and are the patient is currently being followed up without symptoms. CONCLUSION: The pathogenesis of BMPM is unclear. Some authors argue that it is a peritoneal reaction to inflammatory damage, others support that it is a benign neoplasm. This uncertain nature coupled with limited experience make management complex. It is necessary to evaluate each case and try to be conservative especially in young patients. If surgery management is chosen, complete cytoreduction followed by hyperthermic peritoneal chemotherapy is the most successful option. The follow-up in any case must be exhaustive and multidisciplinary, mainly with imaging tests.

Benign Multicystic Peritoneal Mesothelioma in a Male Teen: Case Report and Review of the Literature.

The case of a Peruvian 15-year-old male with a left-flank abdominal mass suspected to be a peritoneal pseudomyxoma is presented. The patient underwent a R0 surgery, and the pathology review showed a benign multicystic peritoneal mesothelioma. Characterized by recurrent mesothelial peritoneal cysts originating in the epithelial and mesenchymal elements of mesothelial tissue, this benign tumor is unusual among young males.

Long-term results of laparoscopic cytoreductive surgery and HIPEC for the curative treatment of low-grade pseudomyxoma peritonei and multicystic mesothelioma.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) provide long-term survival for low-grade pseudomyxoma peritonei (PMP) and multicystic peritoneal mesothelioma (MM). Feasibility of laparoscopic CRS-HIPEC has been reported for selected patients but data regarding long-term outcomes are missing to assess the oncological interest. This study aimed to report long-term outcomes for low-grade PMP and MM treated by laparoscopic approach. METHODS: From a prospectively maintained CRS-HIPEC database, all patients who underwent laparoscopic CRS-HIPEC with curative intent were analyzed. Selection criteria for laparoscopic approach were low-grade PMP or MM, with pathological confirmation prior to CRS-HIPEC, ASA 2, age < 75 years, no extrap-eritoneal disease, Peritoneal Cancer Index (PCI) < 10, and a limited history of abdominal surgery. RESULTS: Between March 2009 and June 2017, 43 patients were scheduled for laparoscopic CRS and HIPEC. Laparoscopic CRS and HIPEC was completed (LSC) in 32 patients and 11 patients were converted to open surgery (CONV). Median age was 44.5 years (17.13-71.4) in the LSC group and 54.9 years (22.5-70.5) in the CONV group (p = 0.086). Median BMI was not different between groups, 21.2 and 23.9 for LSC and CONV groups, respectively (p = 0.267). There were 21 and 11 patients in the LSC group, and 8 and 3 in the CONV group, with PMP and MM, respectively (p = 0.794). Median PCI was 2.5 (0-9) and 7 (1-15) in the LSC and CONV groups, respectively (p = 0.004). There was no difference in the completeness of cytoreduction score (p = 0.256). After a median follow-up of 31.6 months (95% CI 19.3-36.4), 2 patients in the LSC group and 2 patients in the CONV group presented with peritoneal recurrence. CONCLUSION: For selected patients with low aggressive peritoneal disease, laparoscopic CRS-HIPEC provides interesting long-term outcomes.

Benign multicystic peritoneal mesothelioma: literature review and update

Benign multicystic peritoneal mesothelioma (BMPM) is a rare peritoneal tumor diagnosed predominantly in pre-menopausal women. Associated risk factors include endometriosis and pelvic inflammatory disease in women, and prior abdominal surgery in both genders. To date, the pathogenesis of this disease remains controversial with possible etiologies, including a neoplastic versus a reactive process. Given the risk factors, some authors believe that this disease is secondary to a reactive process. However, because some studies describe cases where there is no prior surgical history or inflammatory milieu present, and because of this entity's predilection for recurrence, some authors believe the origin to be neoplastic. Some genetic and familial associations have also been reported. Malignant transformation is extremely rare, with only two cases reported in the literature, despite the recurrence potential. Like the etiology, the name of this entity is also controversial. Some authors prefer the term "peritoneal inclusion cyst (PCM)" instead of "benign cystic mesothelioma" and argue that the term mesothelioma should only be used when there is evidence of atypia. Most cases of BMPM are discovered incidentally. Others reflect sequela of tumor mass effect. It appears intra-operatively as large, multi-focal, cystic lesions in the peritoneal and pelvic cavity. Diagnosis is achieved through surgical sampling with histopathological examination. Immunobiologically, BMPM exhibits multiple small cystic spaces with flattened lining containing calretinin positive cells without atypical features, mitotic figures, or tissue invasion. Treatment includes cytoreductive surgery. Here we present a case of BMPM in a 60-year-old male - a rare disease in an uncommon patient population.

Benign multicystic mesothelioma: a case report of recurrent disease in a young adult with familiarity for renal cell carcinoma.

Benign multi-cystic peritoneal mesothelioma (BMCM) is a very rare disease (about 150 cases observed). The aetiology is currently little-known, and the data collected, without having achieved conclusive re sults, identify two possible causes: neoplastic and reactive inflammatory. This case report refers to a recidivism of BCMC in a patient whose brother, few months before, underwent a left nephrectomy and right renal Radio Frequency Termo Ablation (RFTA) for bilateral papillary renal cell carcinoma. For the recurring trend, the onset in a male young patient without chronic inflammatory diseases evidence, the presence of a first degree relative with a rare carcinoma we supposed a neoplastic aetiology. The available literature suggests that both tumours (BCMC and renal cell carcinoma) are susceptible to oestrogens. This biomolecular mechanism could represent a valid antipathogenic hypothesis.

[Benign multicystic peritoneal mesothelioma]. / Benignus multicysticus peritonealis mesothelioma.

Benign multicystic peritoneal mesothelioma is a rare benign tumor originating from the peritoneum, affecting mostly young, fertile women. Its presentation is non-specific, thus the final diagnosis is made after the histological examination. A young female patient presented with incarcerated inguinal hernia of which an emergency surgery was performed. During the operation a cystic mass neighboring the round ligament in the canal of Nuck was removed. No inguinal hernia was found. The histological examination confirmed the diagnosis of benign multicystic mesothelioma. The patient was referred to a center performing hyperthermic intraperitoneal chemotherapy, where laparoscopic exploration was performed. The second surgery revealed no residual tumor or any other pathology. A 41-year-old male patient, 4 years before presenting at our ward, had an elective umbilical hernia repair surgery. During the operation 2 cm big cystic mass was removed from the peritoneum, and the histological examination revealed benign multicystic mesothelioma. In 2018, acute surgery was performed due to a periappendicular abscess, while during the surgery a multicystic mass situated on the distal end of the appendix was also removed. The pathological finding confirmed the recurrence of the first tumor. The radiological examination did not find any signs of residual tumor mass anywhere else. The chances of malignant transformation in cases of benign multicystic peritoneal mesothelioma are low. The suggested treatment is en bloc surgical removal of the mass, however, in these cases recurrence is still 50%. If during follow-ups the recurrence of the tumor is found, a total peritonectomy or hyperthermic intraperitoneal chemotherapy is advisable. Orv Hetil. 2019; 160(21): 839-843.

Multicystic Mesothelioma of the Omentum Presenting as an Incidental Finding.

Multicystic mesotheliomas of peritoneal origin (also termed benign multicystic mesotheliomas) are uncommon and are exceptionally rare in the omentum. Lack of familiarity of this entity could lead to overinterpretation as a malignancy or present a challenge at frozen section. We describe a case of multicystic mesothelioma arising in the omentum found incidentally at laparotomy for endometriosis. Frozen section evaluation presented a challenge. Grossly, the mass in the omentum was multicystic and mucoid, raising the concern for a mucinous neoplasm. The cysts, however, were lined by flattened cells without atypia. At permanent section evaluation, calretinin positivity confirmed the mesothelial origin. Awareness of this entity is important, as it may be interpreted as a malignancy, particularly intraoperatively.

An unusual cause of acute surgical abdomen: benign multicystic peritoneal mesothelioma associated with adenomatous tumor.

Benign multicystic peritoneal mesothelioma (BMPM) is a rare disease that primarily affects fertile women with previous abdominal surgery. BMPM associated with adenomatous tumor is a single case report, according to our opinion. The patient had a history of abdominal surgery nine years ago for ovarian cysts. Upon admission, the diagnosis was acute surgical abdomen with acute peritonitis signs. The treatment applied consisted in the removal of peritoneal cysts and partial omentectomy. Only immunohistochemical examination established the diagnosis. The aim is to discuss diagnostic and therapeutic difficulties, underlining that there is no consensus on the use of chemotherapeutics. In conclusion, establishing a preoperative diagnosis is difficult if not impossible. One of the causes of acute surgical abdomen may be BMPM. The malignant transformation of this disease is rare, but the disease recurrence rate is over 50%, and it is often recommended to be monitored through abdominal computed tomography.