An 80-year-old Asian man comes to the office for evaluation of fatigue and 4.5 kg (10 lb) weight loss. Medical history is notable for benign prostatic hyperplasia (which is treated with tamsulosin), coronary artery disease, and hypertension. The patient does not use tobacco and drinks 2 shots of whiskey daily. He eats a vegetarian diet. Vital signs are normal. Physical examination shows a nodular prostate and inguinal lymphadenopathy. Serum prostate-specific antigen level is 25 ng/mL (normal:

Question

An 80-year-old Asian man comes to the office for evaluation of fatigue and 4.5 kg (10 lb) weight loss.  Medical history is notable for benign prostatic hyperplasia (which is treated with tamsulosin), coronary artery disease, and hypertension.  The patient does not use tobacco and drinks 2 shots of whiskey daily.  He eats a vegetarian diet.  Vital signs are normal.  Physical examination shows a nodular prostate and inguinal lymphadenopathy.  Serum prostate-specific antigen level is 25 ng/mL (normal: <4.5 ng/mL).  Biopsy of the prostate reveals adenocarcinoma.  Which of the following risk factors is most strongly associated with development of cancer in this patient?

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Explanation: 11ec25c8_d822_0e33_bc81_1fc62b142c71_MD0003_00 Prostate adenocarcinoma is the second most common malignancy in men worldwide. Although most cases are asymptomatic, prostate cancer can present with systemic symptoms (eg, fatigue, weight loss), bone pain (due to metastases), and/or lower urinary tract symptoms. Prostatic nodules or asymmetry on digital rectal examination, inguinal lymphadenopathy, and significant elevation of prostate-specific antigen (PSA) support the diagnosis but are not present in all cases. Confirmation generally requires transrectal biopsy. The greatest risk factor for prostate cancer is advanced age. Men age <40 rarely have prostate cancer, but prevalence steadily increases as age advances; 30%-80% of men age >70 have histologic evidence of prostate cancer. Other risk factors for prostate cancer are less potent, including: Ethnicity: Black men have the greatest risk of prostate cancer and tend to have more aggressive tumors and present at a later stage of disease. Risk is thought to be increased in this population due to genetic predisposition. Although Asian men are at less overall risk for prostate cancer than black, white, or Hispanic men, risk increases when they live in or move to Western countries (likely due to dietary changes) (Choice D). Diet: Diets high in animal fat (eg, alpha-linoleic acid) and low in fruits and vegetables cause a mild increase in risk for prostate cancer. Vegetarian and fruit-heavy diets do not increase risk (Choice F). (Choice B) Alcohol intake does not seem to increase the overall risk of prostate cancer. However, patients who consume excessive alcohol and develop prostate cancer may have more aggressive tumors. (Choices C, D, and E) Most studies indicate minimal or no elevation in the risk of prostate cancer in patients with underlying benign prostatic hypertrophy (BPH). This is supported by the fact that BPH typically affects the central/transitional zone of the prostate, but prostate cancer primarily occurs in the periphery of the gland. Treatment of BPH with alpha-1-adrenergic antagonists (eg, tamsulosin) does not seem to have a strong effect on the development of prostate cancer. In contrast, 5-alpha reductase inhibitors (eg, finasteride, dutasteride), which block peripheral conversion of testosterone to dihydrotestosterone (the more active form), reduce risk. Educational objective: The greatest risk factor for prostate cancer is advanced age; approximately 30%-80% of men age >70 have histologic evidence of prostate cancer. Less-prominent risk factors include black ethnicity and a diet high in meat and low in fruits and vegetables. References: Epidemiology, etiology, diagnosis and treatment of prostate cancer. (http://www.ncbi.nlm.nih.gov/pubmed/25520069)

An 80-Year-Old Asian Man Comes to the Office for Evaluation