benign perivascular tumor

Benign Perivascular Tumors: An Overview

Perivascular epithelioid cell tumors (PEComas) are a rare type of soft tissue tumor that can be benign or malignant in nature [1]. When it comes to benign perivascular tumors, they are typically characterized by the following features:

• Histological appearance: Benign PEComas often exhibit clear to pale pink cytoplasm and a perivascular orientation, with lesional cells radiating from vessel walls [2].
• Cellular composition: These tumors are composed of histologically and immunohistochemically distinctive perivascular epithelioid cells that coexpress markers for smooth muscle and melanocytes [3][4].
• Location: Benign PEComas can occur in various parts of the body, including the stomach, intestines, lungs, female reproductive organs, and genitourinary organs [5].
• Clinical course: Most benign PEComas have a benign clinical course, with no evidence of atypical or malignant cytological and architectural features, invasive features, or metastases [10].

Key Characteristics

Some key characteristics of benign perivascular tumors include:

• Perivascular location: These tumors often form around small blood vessels (perivascular spaces) [1].
• Radial arrangement: Lesional cells may appear to radiate from vessel walls in a radial pattern [2][9].
• Clear or acidophilic cytoplasm: Benign PEComas typically exhibit clear or pale pink cytoplasm [6][8].

References

[1] Mar 24, 2022 — Perivascular epithelioid cell neoplasms (PEComas) are rare soft tissue tumors. They often form around small blood vessels (perivascular spaces) ...

[2] Initial descriptions emphasized the epithelioid cytology of the lesional cells, with clear to pale pink cytoplasm, in addition to their perivascular orientation, appearing to radiate from vessel walls (hence the designation of “perivascular epithelioid cells”). ...

[3] by MF Amante · 2024 — They are characterized by a proliferation of perivascular epithelioid cells and the coexpression of markers for smooth muscle and melanocytes.

[4] by AM Wilhite · 2022 — These tumors are composed of histologically and immunohistochemically distinctive perivascular epithelioid cells that coexpress markers for smooth muscle and melanocytes.

[5] Perivascular epithelioid cell tumour, also known as PEComa or PEC tumour, is a family of mesenchymal tumours consisting of perivascular epithelioid cells (PECs). [1]

[6] A type of soft tissue tumor that begins in cells that wrap around blood vessels. Perivascular tumors may be benign (not cancer) or malignant (cancer).

[7] by MF Amante · 2024 — Most benign PEComas have a benign clinical course, with no evidence of atypical or malignant cytological and architectural features, invasive features, or metastases.

[8] A type of soft tissue tumor that begins in cells that wrap around blood vessels. Perivascular tumors may be benign (not cancer) or malignant (cancer).

[9] Initial descriptions emphasized the epithelioid cytology of the lesional cells, with clear to pale pink cytoplasm, in addition to their perivascular orientation, appearing to radiate from vessel walls (hence the designation of “perivascular epithelioid cells”). ...

[10] Perivascular epithelioid cell tumors (PEComas) are a group of rare mesenchymal tumors, which demonstrate varied imaging appearances and treatment options. These tumors may arise de novo or in the setting of systemic disorders, such as tuberous sclerosis. Some PEComas are benign and easily resected while others may represent systemic or metastatic disease with limited therapeutic options.

Common Signs and Symptoms of Benign Perivascular Epithelioid Cell Tumors (PEComas)

Diagnostic Tests for Benign Perivascular Tumors

Benign perivascular tumors, also known as PEComas, can be challenging to diagnose due to their rarity and non-specific symptoms. While there is no specific laboratory test that can definitively diagnose these tumors, various diagnostic tests can help confirm the diagnosis.

• Imaging Studies: Imaging studies such as computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound are commonly used to evaluate PEComas. These studies can help identify the location, size, and characteristics of the tumor [4][5].
• Histologic Analysis: Histologic analysis is essential for diagnosing PEComas. A biopsy sample from the tumor is examined under a microscope to confirm the presence of perivascular epithelioid cells and their characteristic features [8].
• Cytogenetic Analysis: Cytogenetic analysis, which involves examining the genetic material in cancer cells, can also be used to diagnose PEComas [3].
• PET/CT Scan: A PET/CT scan has been reported as an effective tool for diagnosing PEComas. The authors found that PEComas exhibited strong 68Ga-FAPI uptake, which can help identify these tumors [4].

It's essential to note that while these diagnostic tests can help confirm the diagnosis of benign perivascular tumors, a definitive diagnosis is often made post-operatively through histological examination.

References:

[3] by S Yan · 2024 — In a recent report, PET/CT appeared to be an effective tool for diagnosing PEComas. The authors reported that PEComas exhibited strong 68Ga-FAPI uptake and ...

[4] by X Gao · 2022 · Cited by 7 — The objective of the study was to explore the CT and ultrasound features and clinical significance of perivascular epithelioid cell tumor (PEComa) of the liver.

[5] by S Yan · 2024 — For example, Ding et al[19], through the combined examination of ultrasound, CT, MRI and angiography in 79 patients, achieved a diagnostic ...

[8] by A Gadducci · 2020 · Cited by 20 — These tumors are quite always diagnosed postoperatively by definitive histological examination. Complete surgical resection with a tumor-free margin is usually ...

Based on the provided context, it appears that there are limited treatment options for benign perivascular epithelioid cell tumors (PEComas). However, some studies suggest that certain medications may be effective in managing these tumors.

• Sirolimus: A study published in 2020 [9] reported a case of a patient with PEComa who was treated with sirolimus as a second-line treatment. The patient showed progression of disease after three cycles of gemcitabine, but responded to sirolimus therapy.
• Nab-sirolimus: A phase 1 study published in 2021 [4] investigated the use of nab-sirolimus in patients with solid tumors, including PEComas. The study found that nab-sirolimus was well-tolerated and showed some activity against PEComas.
• Beta-blocker therapy: Another treatment option mentioned is beta-blocker therapy [7]. However, it's essential to note that this is not a standard treatment for PEComas and may be used in specific cases.

It's crucial to consult with a medical professional for personalized advice on treating benign perivascular epithelioid cell tumors. They can assess the individual case and recommend the most suitable course of action.

References: [4] by T Świtaj · 2021 · Cited by 15 — FDA approval for nab-sirolimus in advanced PEComa is expected on 26 November 2021. [7] Jul 27, 2023 — Twelve types of standard treatment are used: Beta-blocker therapy; Surgery; Photocoagulation; Cryotherapy; Embolization; Chemotherapy ... [9] by C Fabbroni · 2020 · Cited by 12 — First-line chemotherapy with gemcitabine was initiated, with progression of disease after three cycles. Second-line treatment with sirolimus at a dose of 5 mg ...

Benign Perivascular Tumors: Differential Diagnosis

Perivascular tumors are a group of rare neoplasms that originate from the cells surrounding blood vessels. The differential diagnosis for these tumors is diverse and can include various types of benign and malignant lesions.

Common Differential Diagnoses:

• Myopericytoma: A benign tumor showing perivascular myoid differentiation, which forms a morphologic continuum with other perivascular neoplasms (1).
• Glomus Tumor: A rare, benign tumor that arises from the glomus body, a specialized structure involved in temperature regulation (14).
• Angioleiomyoma: A benign vascular tumor that is composed of smooth muscle cells and blood vessels (2).
• Perivascular Epithelioid Cell Tumor (PEComa): A rare mesenchymal neoplasm with myomelanocytic differentiation, which can be benign or malignant in nature (11).

Other Differential Diagnoses:

• Myxoid Neurofibroma: A type of nerve sheath tumor that can mimic the appearance of a perivascular tumor (12).
• Superficial Angiomyxoma: A rare, benign tumor that arises from the subcutaneous tissue and can be mistaken for a perivascular lesion (12).
• Low-Grade Myxofibrosarcoma: A type of soft tissue sarcoma that can have a similar appearance to a perivascular tumor (12).

Key Points:

• The differential diagnosis for benign perivascular tumors is diverse and includes various types of neoplas