Author: Travis Giddings
The field of head and neck cancer from ASCO 2012
A recent presentation at the American Society of Clinical Oncology expanded on several molecular breakthroughs concerning head and neck cancers, and a team of doctors gave an overview of recent conclusions from their respective fields.
The newly identified molecular pathway for cancers of the head and neck that involves the epidermal growth factor receptor (EGFR) led to developments of highly effective drugs specific for the cancerous cells, EGFR inhibitors.
Soon afterwards, scientists discovered the increasingly important role that the human papillomavirus (HPV) played in the development of cancers in the head and neck.
Following the explosion of research in the field of molecular pathways involved in head and neck cancers, doctors quickly found that the cancer was a lot more complicated than previous believed. Additional research continues as scientists try to make sense of the data.
Approaching the treatment of head and neck cancer from their perspectives from surgery, radiology, and oncology, doctors on the panel discussed the difficulties the field currently faced.
The director of Johns Hopkins’ Head and Neck Cancer Research department, oncologist David Sidransky, MD, opened the meeting.
“The genetic and epigenetic alterations in human tumors are becoming increasingly important for devising and implementing personalized oncology approaches,” said Dr. Sidransky. “Unlike in some other cancers, in head and neck cancer the common mutations that have been identified have not been very helpful for treatment.”
The chair of the conference was held by Ezra E.W. Cohen, MD, of The University of Chicago, who mentioned that the molecular differences involved in all the different kinds of this classification of cancer was quite challenging.
“We are learning a lot more about the biology of this disease and are beginning to understand just how heterogeneous it is when it comes to molecular profiling, even within HPV-positive and HPV-negative tumors,” Dr. Cohen explained.
As a board-certified surgeon, Robert L. Ferris, MD/PhD, from the University of Pittsburgh Cancer Institute, spoke on the importance of further development in immunotherapies. He stated that research in the use of monoclonal antibodies could hold the key to successful treatment, as so much of the cancer involved a key point of immune system dysfunction.
“T cells are drawn into tumors through chronic antigen stimulation,” Dr. Ferris explained. “They are chronically stimulated and often driven into an exhausted state through chronic antigen exposure.”
With the successful development of targeted antibodies, doctors could learn how to turn off that immune reaction that makes cancers of the head and neck so difficult to treat. Similar to what Dr. Ferris said, treatment with monoclonal antibodies including cetuximab are one of the few glimmers of hope in the research, but results have been underwhelming so far.
Quynh-Thu Le, MD, a radiologist at Stanford University, spoke about the current treatments in use. Radiation therapy has shown some success on its own, but she hopes to take it to the next level by involving the molecular therapies against EGFR. While studies have discussed evidence linking how aggressive head and neck cancers are by identifying low levels of oxygen in tumor sites, finding a solid mathematical relationship has been difficult. Dr. Le also outlined the lack of success that researchers have had in using secondary drugs such as bevacizumab to change blood vessels, theoretically increasing the amount of chemotherapy received by the tumors.
“The thought was that if we could normalize tumor vasculature with antiangiogenic therapy, we could increase oxygen and chemotherapy delivery, thereby enhancing treatment in these tumors,” Dr. Le explained. Unfortunately, testing of the theory showed this was not the case.
The presentation concluded with an appeal by Jill Gilbert, MD, an oncologist at the Vanderbilt Ingram Cancer Center requesting for more doctors currently practicing to become involved in front-line research, sending solid data back to research teams discussing what therapies had shown success.
“This will require us [to] partner with physician–scientists in a broad array of arenas and [to] encourage patient participation and buy-in, because, without them, we are not going to see improvements in these areas,” stated Dr. Gilbert.
1. Material presented at the conference was given as expert-level evidence only rather than a presentation of data from a formal study.