In Singapore, common cancers affecting men and women in recent years are colorectal, breast and lung cancers. But rarer forms of cancers may affect some of us. These include sarcoma and melanoma.
Dr Richard Quek, a senior consultant medical oncologist at Parkway Cancer Centre with a special interest in the management of sarcomas, melanomas and lymphomas, says that sarcoma is not just one disease but is made up of more than 70 diseases, with each having its own behaviour and needing a different treatment plan. Although sarcomas are less common than other cancers – they represent only one per cent of all cancers – they can be more aggressive.
Sarcomas develop from the mesenchymal layer of our body where connective tissue, fat cells, muscles, blood vessels and bones develop from. This is why sarcomas can be found in many parts of the human body, from the skin to the blood vessels, bones and deep organs.
There are four main categories of sarcomas – bone sarcomas, soft tissue sarcomas, gastrointestinal stromal tumours (GIST) and Ewing’s Sarcoma (EWS)/ rhabdomyosarcoma (RMS), each with its own unique natural history and treatment.
Bone sarcoma are cancers that arise from the bone and cartilage. Pain and swelling are the usual first symptoms. Sufferers may initially attribute these warning signs to sports injuries. However, if the pain persists even at rest or occurs at night when one is resting, consult a specialist immediately.
Soft tissue sarcoma (STS) can develop anywhere in the body, from the scalp, head and neck to chest and abdomen including deep organs like the heart and major blood vessels. Dr Quek says that STS can affect any age group but is over-represented in adolescents and young adults. Patients present with an enlarging mass and may have no symptoms until much later in the course of the illness.
Gastrointestinal stromal tumours (GIST) are the most common sarcomas of the gastrointestinal tract. They are located most commonly in the stomach, with smaller numbers arising from the small intestines and rectum. Symptoms from GIST can be very varied depending on the size and location of the tumour. Some of these symptoms include indigestion, bloatedness and blood in stools and vomit.
Ewing’s Sarcoma (EWS) and rhabdomyosarcoma (RMS) are both highly aggressive tumours found in the head, neck, spine or long bones of young adults and children. They are unique group of sarcoma because they are exquisitely chemo-sensitive. Hence multi-agent chemotherapy over an extended period is part of standard of care for this group of patients, in addition to surgery and/or radiation treatment.
As sarcomas can grow anywhere in the body, symptoms can be varied. Common to all, sarcomas can grow to a large size and compress surrounding organs and bring about symptoms related to the location of the tumour. These symptoms may include breathlessness, coughing, abdominal swelling and pain.
So, what exactly makes one prone to sarcoma? Genetic mutations, family history of cancers, exposure to radiation and a damaged lymphatic system are common factors.
To diagnose your condition, your specialist will conduct imaging tests and a biopsy. Dr Quek explains that there is no one-size-fits-all treatment for sarcomas but radiation, surgery, chemotherapy and targeted therapies are commonly used.
A disease that’s not just skin deep
Another cancer that is not so common in Singapore is melanoma. Usually referred to as skin cancer, it actually begins in the melanocytes, skin cells that produce the pigments which give our skin its colour.
Melanoma mainly affects those with a fairer skin tone or those who have excessive exposure to UV radiation from sunlight or artificial tanning. It can also result from gene mutation. In the West, melanomas are typically seen on sun-exposed areas of the skin on the chest, forehead and limbs. In Asia, they more commonly arise from non sun-exposed parts of the body including the hands, feet and even lining of the throat, mouth, gastrointestinal and vaginal tracts.
The good news: you can prevent melanoma by applying sunscreen, wearing long-sleeved clothing and staying out of the sun. Also, melanoma is highly curable if detected early.
The earliest symptoms show up as changes in existing moles or the formation of a new unusual-looking growth on skin. A biopsy of a suspicious lesion is usually performed and examined under a microscope.
Melanoma is best treated with a multi-disciplinary approach. In its early stages, surgery is sufficient. But in patients with advanced melanoma that has spread, targeted therapy against the cancer mutation or immunotherapy that helps to stimulate the patient’s own immune systems to recognise and destroy cancer cells, are effective treatment options. To reduce the risk of a relapse, follow-up preventive treatment is recommended too.