Perivascular epithelioid cell tumour (PEComa)

aka PEComa, Malignant PEComa, Angiomyolipoma and lymphangioleiomyomatosis (PEComa family)

PEComa is a rare tumour of cells that sit around blood vessels and share features of muscle and pigment cells. Most are benign, but malignant ones spread and resist chemotherapy. They usually have lost the TSC1 or TSC2 brake on the growth signal mTOR, and in 2021 the mTOR blocker nab-sirolimus became the first approved treatment.

Part ofSarcomas (soft tissue, bone, GIST)

Perivascular epithelioid cell tumours express both smooth muscle and melanocytic markers (HMB-45, Melan-A) and include renal angiomyolipoma, pulmonary lymphangioleiomyomatosis and clear cell sugar tumour of the lung as well as PEComa not otherwise specified of the uterus, retroperitoneum, gastrointestinal tract and soft tissue. Most carry biallelic loss of TSC1 or TSC2, with or without tuberous sclerosis complex, which unleashes mTOR signalling; a minority instead carry TFE3 fusions and do not respond to mTOR inhibition. Malignancy is predicted by size over five centimetres, infiltrative growth, high grade, necrosis, mitotic count and vascular invasion.

Complete surgical resection is the treatment for localised tumours, with no established role for adjuvant therapy, and surveillance for those with high-risk features. Conventional chemotherapy has little activity in malignant PEComa. Case series of sirolimus, everolimus and temsirolimus showed responses in TSC-altered tumours, establishing mTOR inhibition as the rational systemic therapy.

The single-arm phase 2 AMPECT trial tested albumin-bound sirolimus (nab-sirolimus) in advanced malignant PEComa and reported objective responses in around four in ten patients, with responses lasting years in some and higher response rates in TSC2-mutant tumours, leading to FDA approval in November 2021, the first drug approved for PEComa. The PRECISION 1 basket trial extends nab-sirolimus to any solid tumour with inactivating TSC1 or TSC2 alterations.

State of the art

Nab-sirolimus is the first approved drug for PEComa, with durable responses in TSC2-mutant tumours.
TSC1/TSC2 loss defines a targetable pathway across the PEComa family and beyond.
TFE3-rearranged tumours form a distinct group that needs different treatment.

Red cards

From the labels and guidelines behind the standard of care. Your team's thresholds win.

Emergency services now
Bleeding or bruising
Bleeding that will not stop, black or bloody stools, or unexplained bruising when platelets are expected to be low.
Doxorubicin Gemcitabine source
Check before combining
Food and drink: Doxorubicin
Cumulative dose: risk rises steeply above 400-550 mg/m² (see the anthracycline calculator).
Doxorubicin source
Check before combining
Food and drink: Everolimus
Avoid grapefruit. Live vaccines are contraindicated.
Everolimus source
Check before combining
Liver: Doxorubicin
Reduce by 50% for bilirubin 20-50 µmol/L and 75% for 50-85 µmol/L.
Doxorubicin source
Check before combining
Liver: Everolimus
7.5 mg (mild), 5 mg (moderate), 2.5 mg (severe).
Everolimus source
Good to know
Cardiotoxicity (LVEF decline, cardiomyopathy)
Heart damage from cancer treatment: anthracyclines weaken the heart muscle permanently in a dose-related way, trastuzumab does so reversibly, and some kinase inhibitors raise blood pressure or disturb rhythm. Heart function (LVEF) is monitored by ultrasound during treatment.
Doxorubicin source

See all on the product pages:Doxorubicin Everolimus Gemcitabine·Printable cards in the navigator

Anatomy and lymph node drainage

Bone and soft tissue (limb cross-section): subsites and node stations · wireframe schematic, not to scale

Organ atlas →

Bone sarcomas favour the fast-growing ends of long bones (osteosarcoma) or the shaft (Ewing), soft tissue sarcomas the deep muscle compartments; spread is through the blood to the lungs, rarely via lymph nodes.

Subsites

Metaphysis, near the growth plate (osteosarcoma)
Shaft (Ewing sarcoma)
Deep soft tissue compartmentUterine PEComa (commonest site of malignant PEComa) · Retroperitoneal and abdominopelvic PEComa · Gastrointestinal PEComa · Soft tissue and cutaneous PEComa · TFE3-rearranged PEComa (younger patients; not TSC-driven)
Skeletal muscle (rhabdomyosarcoma)
Neurovascular bundle (limb salvage decision)

Regional lymph nodes

Lymph node spread is rare (except epithelioid, synovial, clear cell and rhabdomyosarcoma); sarcomas go through the blood to the lungs.

Same organ: Leiomyosarcoma, Liposarcoma, Synovial sarcoma, Sarcomas (soft tissue, bone, GIST), Osteosarcoma, Ewing sarcoma, Rhabdomyosarcoma, Chordoma, Desmoid tumour, Tenosynovial giant cell tumour (TGCT), Epithelioid sarcoma, Vascular tumours (angiosarcoma, epithelioid haemangioendothelioma, kaposiform haemangioendothelioma), Chondrosarcoma, Angiosarcoma, Undifferentiated pleomorphic sarcoma (UPS), Myxofibrosarcoma, Alveolar soft part sarcoma, Epithelioid haemangioendothelioma, Malignant peripheral nerve sheath tumour (MPNST), Retroperitoneal sarcoma, Soft tissue sarcoma of the extremity (localised and advanced)

Who gets it and what has changed

A very rare family of tumours, a few hundred malignant cases reported worldwide, arising in the uterus, retroperitoneum, gut and soft tissue of adults, more often women; most are benign, and malignant PEComa was untreatable by chemotherapy until mTOR inhibitors.

Group

sarcoma

Cases by country

Cases by country · GLOBOCAN 2022

All countries →

No country-level case numbers. This cancer is not mapped to a GLOBOCAN site.

Standard of care

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Lines of therapy by subgroup →Staging and risk scores →

Decisions you may face

3 with more than one option · full decision page →

One section per setting: the options named, what each is for, the trials behind them, the recorded trade-offs and the questions to ask.

Localised2 Advanced malignant PEComa3 After mTOR inhibitor2

Localised

Complete resection; surveillance for tumours with malignant features; no proven adjuvant therapy.

Limb-salvage surgery and endoprosthetic reconstruction Active surveillance

Advanced malignant PEComa

Nab-sirolimus (AMPECT; FDA approved 2021); oral sirolimus, everolimus or temsirolimus as alternatives; check TSC status.

Sirolimus protein-bound particlesAMPECTEverolimusTemsirolimusmTOR

After mTOR inhibitor

Anthracycline- or gemcitabine-based chemotherapy has modest activity; trials of mTOR-based combinations; PRECISION 1 for TSC-altered tumours.

DoxorubicinGemcitabinePhase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1)

Subtypes & biomarkers

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Subtypes

Uterine PEComa (commonest site of malignant PEComa)
Retroperitoneal and abdominopelvic PEComa
Gastrointestinal PEComa
Soft tissue and cutaneous PEComa
TFE3-rearranged PEComa (younger patients; not TSC-driven)
Angiomyolipoma and lymphangioleiomyomatosis (related, mostly benign)

Biomarkers clinicians test

TSC1 or TSC2 inactivation (mTOR inhibitor response)
TFE3 fusion (excludes TSC pathway; poor mTOR response)
HMB-45, Melan-A and smooth muscle actin co-expression
Size over 5 cm, mitoses, necrosis and infiltration (malignancy criteria)

How often this target appears

History

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1992Bonetti and colleagues propose the perivascular epithelioid cell concept
2002WHO recognises PEComa as a tumour family
2010Sirolimus responses reported in malignant PEComa with TSC loss
mTOR
2021AMPECT: nab-sirolimus approved for advanced malignant PEComa
AMPECTSirolimus protein-bound particles

What changed

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Dated changes read from the records linked to this cancer: approvals, regulatory steps, reported trials, guideline versions and milestones. Newest first; no date is inferred.

All 7 changes by month →

FollowWatch this cancer and Saved shows what changed since you last looked.Follow by feed

In development

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What is in development for Perivascular epithelioid cell tumour (PEComa), drawn from the whole corpus: 2 items. Drugs are grouped by the most advanced trial phase they have reached anywhere; approved treatments sit under standard of care. Technologies are the methods being tested for this cancer, trials are the studies recorded here, and ideas are proposals not yet in a trial.

Trials under way · 1

Phase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1) · phase 2 · Aadi Bioscience, Inc.

Trials reported · 1

AMPECT · phase 2 · 2021 · positive

Open problems and what is being done

Malignancy cannot always be predicted from histology.
Resistance to mTOR inhibition eventually develops.
TFE3-rearranged PEComa lacks an effective drug.

Trials

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Trials recruiting now

Recruiting trials near you · live from ClinicalTrials.gov

Perivascular epithelioid cell tumour (PEComa)

condition: Perivascular epithelioid cell tumor

Open on ClinicalTrials.gov →

within

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Landmark trials

AMPECT Phase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1)

Expert centres

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Where the expertise is

Expert centres

1 centres in 1 country · 0 with a trial for this cancer on record · second-opinion finder →

Choose a region from the globe in the header to mark centres near you.

1 centres


Mays Cancer Center at UT Health San Antonio San Antonio, TX · cancer center	United States	NCI clinical	0	none recorded	-

These are the things we can measure; they are not a ranking of quality. Each column is a field on the institution record or a count over what OnCo has linked; a centre that treats many patients with Perivascular epithelioid cell tumour but is thinly recorded here will look small.

Not known: OnCo holds no case-volume or outcome figures for centres, so none are shown. Where a national audit or registry publishes them, the centre's page links to it. Default order: Newsweek rank, then trials for this cancer, then research output.

Seeking a second opinion: ask your oncologist for a referral to a high-volume centre; most accept records and pathology by mail or telehealth. In the US, use the NCI's Find a Cancer Center tool or the nonprofit Cancer Commons, which navigates options for advanced cancers at no cost. The second-opinion finder explains how referral works in your country.

Questions to ask

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Bring to your appointment

Questions to ask your oncologist about Perivascular epithelioid cell tumour

Generated from this cancer's standard of care, biomarkers, and pipeline · 16 questions

Newly diagnosed

What is my exact diagnosis, stage, and grade, and which tests established them?
Why: Everything else follows from an accurate stage and subtype.
Which biomarkers have been tested on my tumour (for example TSC1 or TSC2 inactivation, TFE3 fusion, HMB-45, Melan-A and smooth muscle actin co-expression, Size over 5 cm, mitoses, necrosis and infiltration), and what were the results?
Why: These results decide eligibility for targeted therapy, immunotherapy, and trials.
Which subtype is my cancer, and does that change the recommended treatment?
Why: Recognised subtypes for this cancer include Uterine PEComa, Retroperitoneal and abdominopelvic PEComa, Gastrointestinal PEComa.
Is germline (inherited) genetic testing recommended for me or my family?
Why: Inherited variants can change treatment and matter for relatives.

Localised

For my situation (localised), which of the standard options do you recommend and why?
Why: Guideline options include: Complete resection; surveillance for tumours with malignant features; no proven adjuvant therapy.

Advanced malignant PEComa

For my situation (advanced malignant pecoma), which of the standard options do you recommend and why?
Why: Guideline options include: Nab-sirolimus (AMPECT; FDA approved 2021); oral sirolimus, everolimus or temsirolimus as alternatives; check TSC status.
Am I a candidate for Sirolimus protein-bound particles, Everolimus, Temsirolimus, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
How do the results of AMPECT apply to someone like me?
Why: Trial populations differ from individual patients; ask how closely you match.

After mTOR inhibitor

For my situation (after mtor inhibitor), which of the standard options do you recommend and why?
Why: Guideline options include: Anthracycline- or gemcitabine-based chemotherapy has modest activity; trials of mTOR-based combinations; PRECISION 1 for TSC-altered tumours.
Am I a candidate for Doxorubicin, Gemcitabine, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
How do the results of Phase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1) apply to someone like me?
Why: Trial populations differ from individual patients; ask how closely you match.

Any stage

Are there clinical trials I could join, for example of Sirolimus protein-bound particles, Phase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1), AMPECT?
Why: Trials are how the next standard of care is set; asking early keeps options open.
Would a second opinion at a high-volume centre change anything, and can you help arrange it?
Why: Rare or high-stakes decisions benefit from a centre that treats many similar patients.
What supportive care (symptom control, nutrition, exercise, mental health, financial help) is available from the start?
Why: Supportive care improves quality of life and helps patients complete treatment.
I read that “Malignancy cannot always be predicted from histology”. How does that affect my plan?
Why: Open problems are where trials and second opinions matter most.
I read that “Resistance to mTOR inhibition eventually develops”. How does that affect my plan?
Why: Open problems are where trials and second opinions matter most.