5 Genetic Subtypes of Prostate Cancer Discovered
Prostate cancer is the most common cancer in men after skin cancer. The American Cancer Society estimates there to be about 220,800 new cases of prostate cancer this year and about 27,540 deaths. Approximately 1 man in 7 will develop the disease. September is National Prostate Cancer Awareness Month and we here at Path Report have been providing valuable information all month long. Today, let’s look at some of the newest and most exciting research into the disease.
Prostate cancer diagnosis
Prostate cancer is diagnosed by a pathologist. Tissue obtained through biopsy is examined under a microscope. The vast majority of cancers are acinar-type adenocarcinoma. However, there are other morphologic types.
Genetic subtypes of prostate cancer
Researchers from the United Kingdom and Sweden performed genomic profiling in 259 men with prostate cancer. They developed a 100 gene signature that reliably differentiated prostate cancer into 5 distinct subtypes that were predictive of outcome. This is the first study to link genomic findings to outcomes. It will be fundamental to a better understanding of the disease and improved treatments.
This study also lends further support to the concept of approaching cancer diagnosis and treatment based on the unique genetic characteristics of a patient’s tumor. What may look similar under the microscope, can in fact be far different on a molecular level. It is these characteristics that dictate behavior, response to treatment and outcomes.
Such studies highlight the importance of precision medicine. Precision medicine has transformed the approach to treating cancer. In contrast to conventional chemotherapy which involves toxic drugs which kill both cancerous and normal cells, causing many side effects, precision medicine selectively targets a patient’s unique tumor characteristics.
Pathologists are involved in each step of the process. First, a tumor may be biopsied in either the operating room or radiology under CAT scan guidance. Pathologists are called upon to assess the sample, ensuring it is adequate for both diagnosis and testing for precision medicine targets (“actionable mutations”).
In the lab, pathologists examine tissues under the microscope using various stains to make a diagnosis. When appropriate, a tumor is tested for the presence of “actionable mutations”. If discovered, the patient may be eligible for targeted therapy. The success of precision medicine depends on pathologists.