Search Results (9)

Uterine perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm whose sonographic profile has not been systematically characterized. We describe an index case of malignant uterine PEComa and present a PRISMA 2020-compliant systematic review (PubMed, Scopus, Cochrane Library; search 1 March 2026) of studies reporting original ultrasound data of histologically confirmed uterine PEComa. Sonographic features were coded with MUSA/IETA terminology; Clopper–Pearson 95% confidence intervals (CI) were calculated for key proportions, and malignancy subgroups were summarized descriptively. Thirty-one cases were pooled (30 from 18 studies plus our index case; median age 41 years). The profile comprised absent acoustic shadowing in all documented cases (10/10; 95% CI 69.2–100%), moderate-to-abundant vascularisation (Color Score 3–4, 91.7%), variable echogenicity (heterogeneous 56.0%) and predominantly regular margins (69.6%). Preoperative misdiagnosis occurred in 100% of cases, most often as leiomyoma (41.4%). In cases with known malignancy status (n = 17), irregular margins and cystic areas appeared more often in malignant lesions, but subgroups were too small for testing. Only 4/18 studies applied standardized terminology. Uterine PEComa shows a recurrent pattern of absent shadowing, high vascularisation and solid consistency with regular margins that may aid differential diagnosis; systematic adoption of MUSA/IETA terminology in future reports is strongly advocated. Full article

Uterine mesenchymal tumors encompass a diverse and diagnostically challenging group of neoplasms, including smooth muscle tumors, endometrial stromal tumors (ESS), perivascular epithelioid cell tumors (PEComas), inflammatory myofibroblastic tumors (IMTs), uterine tumor resembling ovarian sex cord tumor (UTROSCT), along with many other relatively rare entities. Traditionally classified by histomorphology and immunophenotype, these tumors are now increasingly defined by recurrent genetic alterations that refine diagnosis and elucidate tumorigenesis. For example, leiomyosarcomas display complex genomic instability with frequent TP53, RB1, and ATRX mutations. Low grade-ESS are characterized by JAZF1::SUZ12 and other related fusions, whereas high-grade tumors harbor YWHAE::NUTM2 or ZC3H7B::BCOR fusions, and BCOR internal tandem duplication (ITD) alterations. PEComas frequently contain TSC1 or TSC2 mutations, leading to aberrant activation of the mTOR pathway. Beyond their diagnostic utility, these molecular signatures increasingly inform prognosis and highlight potential therapeutic targets, including CDK4/6 inhibition, PI3K/AKT/mTOR blockade, and immunotherapy. This review summarizes the evolving molecular landscape of uterine mesenchymal tumors, underscoring the value of integrating molecular testing into clinical practice to enhance diagnostic precision and enable personalized management of these rare yet clinically significant neoplasms. Full article

Background: Sclerosing perivascular epithelioid cell tumors (PEComas) are rare mesenchymal neoplasms, typically benign but occasionally exhibiting aggressive behavior. This study reports a case of sclerosing PEComa of the adrenal gland that was treated with robotic partial adrenalectomy, with 13 years of follow-up and a review of the literature. Methods: A 48-year-old woman presented with abdominal pain. Imaging revealed a 10 × 9 cm adrenal mass displacing adjacent structures. MRI and 18F-FDG PET-CT suggested angiomyolipoma. Robotic partial adrenalectomy was performed. Intraoperative frozen section analysis identified the mass as angiomyolipoma, while final histopathology confirmed it as a sclerosing PEComa. Results: This case highlights the advantages of robotic surgery in the management of large adrenal tumors, allowing complete tumor removal while preserving functional adrenal tissue. The extended 13-year follow-up is significant, given the potential for recurrence or malignant transformation reported in other cases. A literature review identified 39 reported cases of sclerosing PEComas, with few documenting long-term outcomes. Conclusions: This is a documented case of robotic partial adrenalectomy for sclerosing PEComa. The findings support robotic surgery as a safe effective approach for managing this rare tumor, with excellent functional and oncological results. Extended follow-up reinforces the tumor’s benign behavior and the importance of long-term monitoring in PEComas. Full article

Background: Perivascular epithelioid cell tumors (PEComas) are a rare group of mesenchymal neoplasms with distinctive histological and immunohistochemical features. This systematic review aims to characterize the clinical presentation, diagnostic approach, treatment, and outcomes of adult patients with hepatic PEComa. Methods: We performed a systematic literature search for English-language articles regarding hepatic PEComas using the terms (perivascular epithelioid cell tumor) OR (PEComa) AND (liver) OR (hepatic), up to 25 May 2025. Results: A total of 145 studies encompassing 281 patients were included in the analysis. Most studies originated from Asia. The mean age at diagnosis was 46 years (IQR: 35.25–53.75) with a female predominance. The underlying comorbidities were uncommon among the reported cases, and more than half were asymptomatic at presentation. The tumor presented as a single liver lesion in almost 9 out of 10 patients. Surgical excision was the primary treatment, and diagnosis in 74% of patients was made with positive immunohistochemistry for markers such as HMB-45 and smooth muscle actin. A malignant phenotype was reported in 30 cases. The median follow-up duration was 24 months (IQR: 12–48); recurrence occurred in 17 patients, and disease-related mortality occurred in 8 patients. Conclusions: Primary hepatic PEComa is a rare liver tumor with mostly benign clinical behavior and non-specific presentation. Future studies are needed to support clinician decisions regarding this entity and improve patient care. Full article

Gynecologic perivascular epithelioid cell tumors (PEComas) are rare mesenchymal neoplasms characterized by the co-expression of melanocytic markers (HMB-45 and Melan-A) and smooth muscle markers (SMA, desmin, and caldesmon). The uterus is the most common organ affected, with approximately 110 cases reported worldwide, while occurrences in the cervix, vagina, ovary, and other gynecologic locations are exceptionally rare. These tumors typically present with nonspecific symptoms such as abnormal uterine bleeding and pelvic pain, often mimicking other uterine neoplasms. Histopathologically, PEComas exhibit epithelioid and spindle cell morphology with variable nuclear atypia, mitotic activity, and characteristic immunohistochemical profiles. Although most PEComas behave benignly, a subset demonstrates malignant potential, associated with larger tumor sizes, an increased mitotic index, necrosis, and vascular invasion; however, standardized diagnostic criteria remain scarce. Molecular alterations frequently involve the mTOR signaling pathway through tuberous sclerosis complex (TSC) 1 and TSC2 gene mutations, offering potential targets for therapy. Surgical resection with clear margins remains the cornerstone of treatment. For advanced or metastatic cases, mTOR inhibitors have shown promising efficacy, whereas the role of radiotherapy remains uncertain. This review aims to synthesize current knowledge regarding the epidemiology, clinical presentation, histologic features, malignant potential, and treatment of uterine PEComas, emphasizing the importance of accurate histopathological classification and molecular profiling to guide individualized therapeutic strategies. Full article

Perivascular epithelioid cell tumors (PEComas) are rare mesenchymal neoplasms characterized by perivascular epithelioid cell proliferation. They can occur in various organs, but colonic PEComas are exceptionally rare, showing diagnostic challenges due to their nonspecific clinical presentation and similar features to those of other colorectal tumors. We present a case of a 61-year-old female with defecation accompanied by blood clots, initially diagnosed with a suspected tumor in the sigmoid colon. Despite initial biopsy yielding non-informative material, repeat colonoscopy and imaging studies revealed a malignant tumor with multinucleated giant (osteoclast-like) cells and probable p53 mutation, most likely of mesenchymal origin. Robotic surgical resection was performed, and ultimately pathological examination refined the diagnosis as a malignant PEComa of the colon. This case demonstrates the importance of considering PEComa in the differential diagnosis of colonic tumors. Further research is needed to ascertain the clinical behavior and optimal treatment for colonic PEComas. Full article

PEComa has become a widely accepted entity, and increased recognition has led to descriptions of this tumor in a wide variety of anatomic sites, including the adrenal gland. PEComa (perivascular epithelioid cell tumor) is a mesenchymal tumor composed of perivascular cells, and the most frequent sites of PEComas are the uterus and retroperitoneum. The incidence is <1 per 1,000,000 people. We report a case of adrenal metastatic PEComa in a 63-year-old man discovered by a spontaneous hematoma of the rectus abdominis. In our case, PEComa of the adrenal gland was a significant diagnostic dilemma as the morphologic and immunophenotypic features of this neoplasm may easily be confused with those of other more commonly encountered lesions. Full article

Background: Perivascular epithelioid cell neoplasms (PEComas) are a diverse family of mesenchymal tumors with myomelanocytic differentiation that disproportionately affect women and can be associated with tuberous sclerosis (TS). Although mTOR inhibition is widely used as first-line treatment, it is unclear what genomic alterations exist in these tumors and how they influence the response to therapy. Methods: This was a multicenter study conducted at five sites within the US. The data were collected from 1 January 2004 to 31 January 2021. We conducted a retrospective analysis to identify PEComa patients with next-generation sequencing (NGS) data and compared outcomes based on mutations. Results: No significant differences in survival were identified between TSC-1 and TSC-2 mutated PEComa or TSC-1/-2 versus other mutations. No significant difference was seen in progression-free survival (PFS) after first-line therapy between mTOR inhibition versus other systemic therapies. Conclusions: We were unable to detect differences in survival based on genomic alterations or PFS between mTOR inhibition versus other systemic therapies. Future studies should seek to identify other drivers of TSC-1/-2 silencing that could predict response to mTOR inhibition. Full article

Perivascular epithelioid cell tumors (PEComas) represent a family of rare mesenchymal neoplasms, some of which are malignant. There are no specific management guidelines for PEComas, and factors correlating with the disease course are not well defined. This analysis aimed to describe the outcomes of PEComa patients treated radically, including those treated exclusively in the national reference sarcoma center. The secondary aim of the study was to analyze factors associated with PEComa treatment efficacy. We performed an analysis of 27 patients subsequently treated radically for PEComa between 1999 and 2019 who were in follow-up in the national sarcoma reference center. The proportional-hazards model was used to compare the risk of death. The median age at diagnosis was 45 (21–67) years, and 67% of patients were female. The median follow-up period was 68 months (95% CI: 39–101). At the time of analysis, eleven patients (40.7%) experienced progression of the disease and four (14.8%) died. Surgery in the reference sarcoma center was associated with a longer disease control (log-rank p < 0.001). The 5-year-OS rate was 88% (95% CI: 74–100) for the whole analyzed group. We concluded that PEComa treatment should be managed in reference sarcoma centers by a multidisciplinary tumor board with an experienced surgical team. Microscopically radical resection is associated with a longer disease-free survival. Patients requiring long-term follow-ups as late recurrence may be expected. Full article