The State of the Fight: Esophageal Cancerby Steven H. Lin, M.D., Ph.D.
Filed under | The State of The Fight
One of my major motivations as a physician-scientist is to make a difference in diseases like esophageal cancer where mortality rates remain high despite medical advances. In recent decades the incidence rate for esophageal cancer in the U.S. has continued to rise. There is a need for more in depth research and medical advancement, so that we can Continue to improve diagnosis and treatment for patients who are suffering.
The two most common types of esophageal cancer are squamous cell carcinoma and adenocarcinoma. In the U.S., the rates of adenocarcinoma of the esophagus have increased in the past 20 years, while squamous cell carcinoma cancer rates have begun to decrease. The majority of these esophageal cancers arise from chronic irritation and damage of the esophageal lining caused by diet, and personal habits such as: smoking, alcohol, nitrosamines (squamous cell carcinoma), or by gastroesophageal reflux disease (GERD), which is generally linked to adenocarcinoma. Other risk factors include vitamin deficiency, dietary intake and genetics. These factors result in damage to the cells that line the esophagus, where over time aberrant cells arise from the damage to the DNA, creating a preneoplastic state that ultimately leads to cancer. Some symptoms include trouble swallowing, or weight loss.
Even with the increase in occurrence for esophageal cancer, great strides have been made in the diagnosis and treatment of this disease in the last 20 years. Technologies related to endoscopy and imaging (CT scans, PET scans) have improved diagnosis and staging. Surgical techniques and peri- and post-operative care have improved, so that the morbidity and mortality of surgery is minimized. Currently, radiation and chemotherapy are still the main treatment options for esophageal cancer. Radiation has become more targeted, and chemotherapy continues to improve as we learn more about how cancers develop and grow. Advances in supportive care have also allowed patients to get through the aggressive and often toxic treatments with greater tolerability and a better quality of life. Still, we must do better.
Every tumor is unique. Therefore, the future of treatment and research in esophageal cancer lies in molecular biology, where we hope that by learning the genetics of both the patient and the tumor, genetic “traits” will allow doctors to create personalized treatments. Not only will these types of treatments more effectively kill the cancer cells, they will also be less toxic.
I am currently a collaborator in the SU2C Circulating Tumor Cell (CTC) Chip Dream Team at MD Anderson. The CTC Chip is a medical device that efficiently captures rare cancer cells free floating in the blood (aka CTCs). We hope that the ability to detect and characterize CTCs in cancer patients will lead to earlier diagnosis and better therapies. This is certainly true for lung cancer patients, but also holds true for esophageal cancers.
An important thing to know about esophageal cancer is that it is a treatable disease, especially if it can be caught at an early stage. One key aspect of cancer treatment is the proper staging of patients, since the types of treatment are fully dependent on whether the cancer is metastatic or non-metastatic. We rely on imaging to tell us whether the patient has metastatic disease. However, even with the most sensitive scans, we are still unable to detect micrometastatic disease that escapes the detection of most modern radiologic imaging. Often a local treatment such as surgery or radiation is rendered for treatment of what was felt to be localized disease, but after a prolonged course of treatment the patient may have these micrometastatic sites develop into detectable metastatic disease. The ability to detect and characterize these rare tumor cells in the blood will be a major breakthrough in how esophageal cancers will be staged and how response to treatment will be assessed in the future.
The creation of the CTC Chip Dream Team is a major endorsement by SU2C of the need for innovative ways to help improve how esophageal cancer is detected and treated. This effort brings together talented individuals on the forefront of this research in order to accelerate the development of technologies and discoveries that are necessary to make an impact on patient care in the near future.
There is still so much we don’t know about esophageal cancers. In 2010 there were an estimated 16,640 new cases of esophageal cancer and 14,500 deaths from it in the U.S. alone. We as physicians and researchers are still learning more about genetics and why certain esophageal cancers are more aggressive than others. However, esophageal cancer is, for the most part, a preventable disease. Prevention and public awareness is needed to reduce the incidence of this devastating disease worldwide. The National Cancer Institute and MD Anderson both have wonderful additional resources for anyone looking to learn more about prevention and treatment options for esophageal cancer. Additional funding for research to improve the cure rate is still greatly needed. With more research, we can improve our knowledge of esophageal cancer, to better prevent and treat patients stricken with this disease.