Genitourinary Cancer – 5
(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Thank you Chiragbhai for interesting points about germ cell tumors arising from other sites like mediastinum and retroperitoneum. Famous cricketer Yuvraj Singh also had mediastinal germ cell tumor. Important to avoid bleomycin in mediastinal tumors; rare association of mediastinal GCTs with rare hematological disorders. GCTs also arise from ovary, and are overall treated in similar manner as testicular tumor.
Now can we go to the commonest tumor of genitourinary region i.e. prostate carcinoma.
Answer: Sure. Prostate cancer has a very high incidence in USA/Europe. Africans also have a significantly high incidence, and comparatively more aggressive disease. Incidence is rising in India too. This cancer is believed to be associated with lifestyle changes primarily. However, a significant proportion of patients have a family history of this cancer, and a small proportion are associated with identifiable mutation like BRCA gene mutation. Smoking increases risk somewhat. Obesity is clearly associated with increased risk. High fat diet, especially animal fat, increases risk.
Comparison of incidence between countries is not accurate, since western countries have wider PSA screening. And their incidence rate has reduced after routine PSA screening recommendation was changed to less frequent screening and screening after discussion with an individual.
Que: What is the role for PSA test in early diagnosis?
Ans: PSA (prostate specific antigen) is a simple blood test, widely available, and relatively cheap which can detect prostate cancer early. However, this is one of the most controversial cancer screening tests, due to high rate of false positives. That means a large number of people with high PSA detected during routine tests do not actually have cancer, and hence undergo unnecessary biopsy. Additionally, a large number of cancers detected by PSA are in such early stage that they do not need any treatment. But they end up undergoing treatments, with potentially significant risks in some cases, as it is difficult for most patients not to undergo treatment once they are diagnosed with a serious illness like cancer. According to autopsy studies in USA, about 70% of men over age 80 years have asymptomatic prostate cancer. That means these people died of some other disease, and knowing about cancer would not have made any difference to their life (length of life or quality of life). Such patients are often diagnosed by large scale screening and end up undergoing unnecessary treatments.
Various international guidelines have repeatedly mentioned about the need to discuss advantages and disadvantages of screening with patient, before ordering PSA test. Rather than just ordering it for every man above age 50. Patients with family history should consider it more strongly. For most others, it should not be ordered routinely. In India, since incidence is lower than western countries, mass screening with PSA cannot be recommended as a routine. Unfortunately, however, it is being offered by most hospitals and laboratories as part of routine blood panels.
Que: Oh! This is very complicated. Does this mean we should not be ordering PSA routinely, every year, for every man above age 50, in India? If yes, then how should we detect prostate cancer early?
Ans: You are right. We should not be ordering without understanding its limitations. Many men will undergo unnecessary anxiety, biopsy and occasionally serious complications from biopsy due to such testing. More important is to test for PSA when there are symptoms suggestive of prostate enlargement, confirmed by ultrasound. If there are any signs to suspect cancer on examination (such as hard prostate or hard nodule), and before prostate surgery, a PSA test should be done. PSA can increase even in benign prostatic hypertrophy, a very common condition in elderly. Signs of prostate enlargement in general are, difficulty passing urine, taking long time to pass urine or start flow of urine, increased frequency of urine, need to wake up multiple times at night to pass urine, blood in urine, painful urination etc. If any of these symptoms persist for several weeks, one should be evaluated by a doctor, including examination of prostate, sonography, urine test. And PSA if required based on this evaluation.
February 13th 2018.
Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001. Diplomate American Board of Oncology and Hematology. Ahmedabad. email@example.com