Simple swelling could be more than infection: Doctors shares warning signs that may point to soft tissue cancer
New Delhi: Most people dismiss a small swelling or lump as a muscle strain, an insect bite, or a minor infection. In many cases, that assumption is correct. However, when a lump continues to grow, keeps coming back after treatment, or refuses to disappear despite antibiotics, doctors say it should never be ignored. While such cases are uncommon, these could occasionally be the first signs of soft tissue sarcoma – a rare cancer that develops in the body’s muscles, fat, nerves, blood vessels, tendons, and other connective tissues.
Experts emphasise that recognising these warning signs early can make a significant difference, often allowing more effective treatment and improving the chances of preserving the affected limb.
What is soft tissue sarcoma
Soft tissue sarcoma (STS) is a rare group of cancers that arise from the body’s soft tissues, including muscles, fat, fibrous tissue, nerves, tendons and blood vessels. More than 70 different subtypes of soft tissue sarcoma have been identified. Although it accounts for less than 1 per cent of all adult cancers, the disease can occur at any age, with most cases diagnosed in adults.
The exact cause remains unknown in most patients. However, certain inherited genetic syndromes, previous exposure to radiation therapy and prolonged exposure to specific industrial chemicals have been associated with a higher risk of developing the disease.
“Most swellings are not cancerous, but any lump that continues to grow, keeps recurring or fails to respond to treatment deserves proper evaluation rather than repeated assumptions that it is just an infection,” says Dr Vivek Bande, Consultant Surgical Oncologist, TGH Onco Life Cancer Centre, Talegaon to News9 Live.
Warning signs you should never ignore
Doctors advise seeking medical attention if you notice any of the following:
1. A lump that keeps increasing in size
A swelling that gradually becomes larger over days or weeks is one of the most common warning signs of soft tissue sarcoma. Many sarcomas begin as painless lumps and may grow slowly before becoming noticeable.
2. Swelling that doesn’t improve with treatment
If antibiotics or routine treatment for an assumed infection fail to reduce the swelling, further investigation is warranted instead of repeated courses of medication.
3. A painless lump
Contrary to popular belief, the absence of pain does not necessarily mean a lump is harmless. In fact, many soft tissue sarcomas are painless during their early stages and only become painful when they grow large enough to compress nearby nerves, muscles or blood vessels.
4. Restricted movement
A swelling affecting the arms or legs may gradually interfere with movement or make routine activities difficult because of its size or location.
5. A lump that keeps returning
If a swelling disappears after treatment but repeatedly returns in the same location, it should be evaluated by a specialist.
6. Unexplained weight loss and fatigue
Although less common in early disease, persistent weight loss, unusual tiredness and an enlarging lump together warrant prompt medical assessment.
“One of the biggest misconceptions is that a painless lump cannot be serious. Unfortunately, many soft tissue sarcomas cause little or no pain initially, which is why people often delay seeking medical advice,” Dr Bande explains.
How is soft tissue sarcoma diagnosed
Doctors begin with a detailed clinical examination and imaging studies. Ultrasound is often the first investigation for a superficial lump, while MRI is considered the preferred imaging test for evaluating suspected soft tissue sarcomas because it provides detailed information about the tumour’s size, location and relationship with surrounding tissues.
If imaging raises suspicion, a core needle biopsy is performed to obtain a tissue sample. Experts recommend that biopsies be planned by specialists experienced in treating sarcomas, as this helps guide future surgery and treatment decisions.
Early diagnosis can improve outcomes
Treatment usually depends on the tumour’s size, grade and stage but commonly involves surgery, often combined with radiotherapy and, in selected cases, chemotherapy or targeted therapies. When diagnosed early, many patients can undergo limb-sparing surgery instead of amputation, highlighting the importance of timely referral to a specialised sarcoma centre.
“Early diagnosis not only improves the chances of successful treatment but can also help preserve the affected limb and reduce the complexity of surgery. If a lump persists for more than a few weeks or continues to enlarge, don’t ignore it. Get it checked,” advises Dr Bande.
Most lumps and swellings are caused by harmless conditions such as infections, cysts, lipomas or minor injuries—not cancer. Nevertheless, experts stress that any lump that persists, enlarges, recurs or behaves unusually should be medically evaluated rather than self-treated repeatedly. While soft tissue sarcoma is rare, recognising the warning signs early offers the best chance of successful treatment and better long-term outcomes.