Leiomyosarcoma is a rare cancer of smooth muscle cells, the involuntary muscle found in the womb, the walls of blood vessels, the digestive tract and the skin. The most common sites are the uterus, the back of the abdomen (retroperitoneum) and the limbs.
It is a sarcoma, which behaves differently from the far more common carcinomas and should be treated by a specialist sarcoma team. It is not a fibroid that has been neglected: uterine fibroids are benign, and transformation into leiomyosarcoma is, at most, extremely rare.
Symptoms
- A lump in a limb or the trunk that is growing, deep or larger than about 5 centimetres
- Abdominal swelling, fullness or pain with retroperitoneal tumours
- Abnormal vaginal bleeding, pelvic pressure or a rapidly enlarging womb, especially after the menopause
- Leg swelling from a tumour of a large vein
- Weight loss and tiredness
- Often no symptoms until the tumour is large
Causes and risk factors
For most patients no cause can be identified. Recognised risk factors are previous radiotherapy to the area, usually many years earlier, and inherited conditions including Li-Fraumeni syndrome and hereditary retinoblastoma. Long-term tamoxifen use is weakly associated with uterine sarcomas. There are no established dietary or lifestyle causes. It mainly affects people over 50.
How it is diagnosed
- MRI of the affected area: Best for limb, pelvic and uterine tumours. No scan can reliably distinguish a uterine leiomyosarcoma from a fibroid beforehand.
- CT of chest, abdomen and pelvis: Stages the disease; the lungs and liver are the usual sites of spread.
- Core needle biopsy planned by the sarcoma team: Gives the diagnosis and grade. Suspected retroperitoneal and limb sarcomas should be biopsied before any surgery.
- Expert pathology review: Sarcoma diagnoses are revised in a meaningful share of cases on specialist review, so this step is worthwhile.
Treatment options
- Surgery with clear margins: The central treatment. For the uterus this means hysterectomy with the tumour removed intact. Morcellation, cutting the womb into pieces for keyhole removal, must be avoided when sarcoma is suspected.
- Radiotherapy: Before or after surgery for limb and some trunk tumours to reduce local recurrence.
- Chemotherapy: Doxorubicin-based combinations, gemcitabine with docetaxel, trabectedin and other agents for advanced disease. Its role after complete surgery is decided case by case.
- Treatment of limited spread: Surgery or ablation of a small number of lung deposits in selected patients.
- Hormone therapy: Aromatase inhibitors for some slow-growing, hormone receptor positive uterine tumours.
- Clinical trials: Worth asking about, given the rarity of the disease.
When it is urgent
Heavy vaginal bleeding, sudden severe abdominal pain, a swollen painful leg, or breathlessness need urgent local assessment. A lump that is growing should be referred within two weeks, not watched.
Travelling to Türkiye for treatment
For a rare cancer, review by a high-volume sarcoma team improves the quality of decisions, and this can begin remotely with your scans and pathology slides. Travelling for the operation itself is reasonable if there is no sarcoma service near you. Allow two to four weeks depending on the site. Chemotherapy cycles and scans every three to four months afterwards are better arranged at home. If a leiomyosarcoma was found unexpectedly after fibroid surgery, seek specialist advice quickly about what further treatment is needed.
Send your reports, scans and a short history and a Clinic-Y coordinator replies within 24 hours with suitable teams and written, all-inclusive proposals side by side. Reviewing your case is free.
Frequently Asked Questions
Did my fibroids turn into cancer?
Almost certainly not. Leiomyosarcoma is thought to arise independently, and fibroids are extremely common while this cancer is rare.
Why is a specialist centre stressed so much?
Correct biopsy planning, surgery and pathology depend on experience that general units seldom accumulate with rare tumours.
Is chemotherapy always needed after surgery?
No. For many completely removed tumours the benefit is uncertain, and the decision is individual.
How often will I be scanned?
Usually every three to four months for the first two to three years, then less often.