Immunotherapy drugs used as single agent therapies are so far showing little effect in treating sarcomas, according to an Adelaide-based sarcoma specialist, Dr Ganessan Kichenadasse. He says that while there have been some positive steps forward in treating sarcomas in the past 20 years, there is much more to be achieved. Dr Kichenadasse predicts the next advances will result from combination treatment approaches, combining immunotherapy agents with chemotherapy, as well as employing newer targeted agents. To mark Sarcoma Awareness Month 2020, he shares the following insights.
I am always astounded and humbled by the resilience of my patients facing a cancer diagnosis especially sarcomas due to the complex maze of journey they undertake pre and post diagnosis.
Sarcoma can be a difficult disease to treat and it does require a complex multidisciplinary team involvement.
We really don’t know why most sarcomas happen, but we do know of some pre-disposing factors, like familial links, or strong exposure to toxic chemicals or radiation. Often the first sign someone has a sarcoma is when they develop a mass or a lump, usually on their limbs. However, sarcomas can arise anywhere in the body. The symptoms depend on the location when either cause pain, or pressure related symptoms from masses. It may be back pain, or it can present as a blocked kidneys or rarely bowel obstruction. If it is a soft tissue sarcoma in the uterus, the patient may experience pain in the lower abdomen, or pelvis with or without vaginal bleeding.
The outlook for the patient really depends on the type of sarcoma and the stage of diagnosis. The good news is that most patients can be cured if they are diagnosed early. But once the disease has metastasised and spread to another organ – most likely the lung, liver, lymph nodes — the five-year survival outcomes are not so good. Only 10 to 15% of patients live five or more years in the advanced stages of the common varieties of aggressive sarcomas. Sarcomas absolutely remain an area of high unmet need.
In the past two decades, we have definitely seen progress in how sarcomas are managed, and outcomes have also improved – even for those with advanced disease.
Until recently, we had traditional chemotherapy drugs like and doxorubicin and ifosfamide. Since then, there have been three more drugs increasingly used for second line treatment. However, the response rates to these have been around 10%.
The hope moving forward is in combination approaches. Unlike other cancers, sarcomas are not as sensitive to immunotherapy – despite our initial expectations. Some particular types of sarcoma might have a higher response rate – like pleomorphic sarcoma or leiomyosarcoma. To date, we have examined immunotherapy agents as single agent therapies. I believe the next advances in sarcoma treatment will come from using these agents in combination with chemotherapy and oral targeted agents. As a clinician, it is important we work collaboratively with our peers around the country and internationally to continue finding new answers.
What would I say to patients? I would say that there is always hope for improvement in outcomes of patients with sarcomas. Always look for participating in clinical trials when possible.”
To learn more about sarcoma, clinical trials, or to find a sarcoma specialist, please visit www.sarcoma.org.au