Patient's question:
Here is the translation of the provided content into English, with the specified requirements followed:---
Recently, my son noticed that his nipple has been bleeding. Of course, it's not a lot—just a few bloodstains on his clothes. One time, he accidentally bumped it, and it bled quite a bit. Later, he went to the hospital for a check-up. The doctor treating him is a relative of mine. The doctor felt a lump and said it might be a cyst, so we went together for an ultrasound. However, the ultrasound results only showed a tiny thing, about 1mm x 3mm, which looked like a lump. The doctor who performed the ultrasound said it could be due to capillary bleeding. My relative mentioned that capillary bleeding wouldn't cause this much blood. In the end, the doctor suggested waiting for a month and then coming back for another check-up.
I'm asking: How many possible causes could there be for nipple bleeding in a 29-year-old man like my son?
---
Let me know if you'd like any refinements!
Doctor's answer:
Hello; Male nipple discharge is extremely rare, but if it occurs, whether it is bloody or of other colors, malignant cases are predominant, and medical attention should be sought promptly. The general cause is still unclear. The occurrence of nipple discharge not only affects women's health but also leads to gynecological diseases. Therefore, it is best to undergo a gynecological examination at the hospital to identify the cause and receive symptomatic treatment. In daily life, it is important to drink more water and pay attention to personal hygiene.