Progress in the management of five rare but difficult-to-treat cancers topped all other advances in clinical cancer last year, as highlighted in Clinical Cancer Advances, an annual publication of the American Society of Clinical Oncology (ASCO).
Although rare cancers collectively account for about 20% of all cancers, progress in treating the diseases lagged behind developments in many of the more common cancers. That began to change in 2018, as new therapies and indications had an impact on five rare cancers:
- Anaplastic thyroid cancer (ATC)
- Desmoid tumors
- Midgut neuroendocrine tumors
- Uterine serous carcinoma
- Tenosynovial giant cell tumor (TGCT)
“ASCO’s 2019 Advance of the Year, progress in treating rare cancers, reflects the impressive gains we’ve made in understanding these so-called ‘orphan diseases’ and in tailoring treatments to target their unique characteristics,” ASCO President Monica M. Bertagnolli, MD, said in the introduction to the report.
The 14th edition of the report also introduced a list of research priorities to continue the momentum reflected in advances singled out in the report.
During 2018, the FDA approved the first treatment for ATC in almost half a century, expanding indications for the targeted combination of dabrafenib (Tafinlar) and trametinib (Mekinist). The approval was based primarily on results of a study showing that more than two thirds of patients had tumor shrinkage when treated with the combination. Another drug already on the market, sorafenib (Nexavar), improved progression-free survival in patients with desmoid tumors, a type of sarcoma.
Patients with advanced midgut neuroendocrine tumors benefited from the FDA approval of 177Lu-dotatate, a nuclear medicine therapy that delivers a dose of radioactive material directly to a tumor. In a randomized clinical trial, the treatment reduced the risk of disease progression or death by 79% compared with standard therapy.
Trastuzumab (Herceptin), widely used in the treatment of breast and gastric cancers, proved effective for slowing the progression of uterine serous carcinoma, an aggressive form of endometrial cancer. Finally, the investigational agent pexidartinib, which inhibits a growth factor involved in the progression of TGCT, led to objective responses in almost 40% of patients in a phase III clinical trial. None of the responding patients had disease progression after a median follow-up of 6 months.
In addition to the Advance of the Year, the following other developments in clinical cancer received recognition in the ASCO report:
- Continued progress in molecular diagnostics
- New targeted therapies that slow the progression of breast and lung cancers
- Expansion of microbiome research
- Continued progress in immunotherapy
For the first time, the report included a list of research priorities addressing “areas of vital unmet need or knowledge gaps that could significantly improve clinical decision making”:
- Better strategies to predict response to immunotherapies
- Improved methods to identify patients likely to respond to adjuvant therapy
- Increased emphasis on precision medicine in pediatric cancers
- Optimized care for older patients with cancer
- Improved access to clinical trials
- Reducing adverse effects of cancer treatment
- Countering obesity and its impact on cancer incidence and outcomes
- Better detection and treatment of premalignant lesions
“These priorities represent our vision for finding the next generation of cancer cures and reducing cancer’s impact on patients’ lives,” said ASCO chief medical officer Richard L. Schilsky, MD. “From prevention through survivorship, these priorities are intended to identify areas where progress is most needed and most promising.”
The full report is available on the ASCO website and in the Journal of Clinical Oncology.