VERY-RARE CANCERSarcomaWHO 5th Edition Classification

Alveolar Soft Part Sarcoma (ASPS)

Very Rare Malignancy (1–5 cases per 1,000,000 / year) • Clinical Staging, Genomic Targets & Vetted Specialists

A slow-growing but persistently metastasising soft-tissue sarcoma driven by the ASPSCR1-TFE3 fusion. It is unusual among sarcomas in that patients often live for years even with metastatic disease, and in that it responds to immunotherapy rather than conventional chemotherapy.

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Emergent Referral AdvisoryImmediate Action

Certain rare malignancies progress rapidly or carry acute risk of airway obstruction, acute spinal compression, hydrocephalus, or biopsy-seeding. Do not perform needle biopsy or surgery outside of an NCI-designated specialty sarcoma or neuro-oncology unit without multidisciplinary tumor board review.

Report immediately to an emergency department or tertiary oncologist upon:

  • Consider baseline brain imaging - brain metastases are unusually common
Who It Affects

Adolescents and young adults, median 20-30; slight female predominance

Annual Incidence

Approximately 1% of soft-tissue sarcomas; under 1 per million per year

Clinical Evidence Review

Last audited: 2026-08-13 against NCCN, ESMO, and WHO 5th ed. guidelines.

Clinical Presentation & Hallmark Symptoms

Presenting signs most frequently observed across clinical case series

A painless, slowly enlarging soft-tissue lump, often in the thigh or buttock
In children, a mass in the head and neck including the tongue or orbit
Symptoms from lung metastases - cough or breathlessness
Headache or seizures from brain metastases
Often found incidentally; metastases may be the first presentation

Genomic Profiling & Defining Molecular Lesions

Critical diagnostic fusions, somatic mutations, and therapeutic targets

Rare malignancies frequently depend on distinct oncogenic drivers rather than conventional environmental carcinogens. Comprehensive Next-Generation Sequencing (NGS comprehensive panel) and FISH/IHC are mandatory to establish the true diagnosis and screen for basket trial agents.

ASPSCR1(ASPL)-TFE3 fusion, der(17)t(X;17)(p11;q25)TFE3 nuclear positivity by IHC

Standard-of-Care Treatment Protocol

Frontline and multimodal strategies established under international consensus guidelines

1

Wide surgical excision of the primary tumour

Administered in specialized high-volume oncology programs with subspecialty pathology and organ-preservation protocols.

2

Atezolizumab (regulatory-approved for advanced ASPS)

Administered in specialized high-volume oncology programs with subspecialty pathology and organ-preservation protocols.

3

Antiangiogenic tyrosine kinase inhibitors - cediranib, sunitinib, pazopanib

Administered in specialized high-volume oncology programs with subspecialty pathology and organ-preservation protocols.

4

Metastasectomy for limited lung disease

Administered in specialized high-volume oncology programs with subspecialty pathology and organ-preservation protocols.

5

Radiotherapy for local control or symptomatic metastases

Administered in specialized high-volume oncology programs with subspecialty pathology and organ-preservation protocols.

Clinical Trial Advisory: For rare and ultra-rare malignancies, enrollment in an active clinical trial or expanded-access program is widely considered the preferred standard of care by ASCO and NCCN panels.

Prognosis & Disease Trajectory

Objective clinical outlook without false reassurance

Better than most metastatic sarcomas despite frequent spread. Five-year survival with localised disease is high; with metastases, multi-year survival is common and has improved further with immunotherapy.

Note: Statistics reflect cohort averages. Individual outcomes depend heavily on performance status, resectability, biomarker expression, and timely access to specialized tertiary care.

Active Research, Biomarkers & Clinical Trials

Novel investigational agents, phase I/II trials, and international rare disease consortia

Checkpoint inhibitor combinations with antiangiogenics, and direct TFE3 fusion targeting, are the leading directions. Brain metastasis surveillance is an area of evolving guidance.

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Expert Clinicians

Verified Specialists for Alveolar Soft Part Sarcoma

Browse All Oncologists

Dr. Breelyn Wilky

Sarcoma Oncologist

10+ yrs exp

UCHealth

Denver, USA

Sarcoma OncologyASPSTKI Trials
Vetted DirectoryConsult Specialist

Dr. Richard Quek

Senior Consultant Medical Oncologist

16+ yrs exp

Sarcoma Specialist

Singapore, Singapore

Sarcoma OncologyASPSTargeted Therapies
Vetted DirectoryConsult Specialist

Dr. Peter Hohenberger

Surgical Oncologist

25+ yrs exp

University Hospital Mannheim

Mannheim, Germany

Soft-tissue SarcomasASPSSurgical Resection
Vetted DirectoryConsult Specialist

Dr. Ashish Gulia

Orthopedic Oncologist

15+ yrs exp

Tata Memorial

Mumbai, India

Orthopedic OncologyASPSSarcoma Guidelines
Vetted DirectoryConsult Specialist
Hospital Network

Designated Cancer Centers with Dedicated Programs

Search All 72 NCI Centers

Memorial Sloan Kettering Cancer Center

NY

NCI-Designated Comprehensive Cancer Center

World-leading rare tumor board & pediatric solid tumor protocols

Proton TherapyCAR-T Cell TherapyRobotic Surgery
1,000+ Active Clinical TrialsView Center Profile

University of Texas MD Anderson Cancer Center

TX

NCI-Designated Comprehensive Cancer Center

Largest specialized rare cancer and sarcoma multidisciplinary program

Proton TherapyCAR-T Cell TherapyCyberKnife SBRT
1,200+ Active Clinical TrialsView Center Profile

Dana-Farber / Harvard Cancer Center

MA

NCI-Designated Comprehensive Cancer Center

Pioneering genomic molecular tumor boards & rare histologies

Proton TherapyCAR-T Cell TherapyPhase I Unit
1,100+ Active Clinical TrialsView Center Profile

Mayo Clinic Comprehensive Cancer Center

MN

NCI-Designated Comprehensive Cancer Center

High-volume surgical oncology & rare endocrine/neuroendocrine expertise

Proton TherapyCAR-T Cell TherapyCyberKnife SBRT
600+ Active Clinical TrialsView Center Profile

Frequently Asked Clinical Questions

Authoritative guidance on diagnosis, tumor boards, genomic markers, and care options

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Independent Tumor Board Review

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