What Causes Itching At The Base Of Scalp And Armpits?

I have been having drenching night sweats for a year now. At my last physical I mentioned it to my dr and she ordered a hormone blood test. I m 33 so not menopause. All my tests were normal. She said this May just be my new normal. For the last 4 months I have had extreme itching at the base of my scalp and both arm pits. Should I be concerned about lymphoma? No other symptoms to report in relation to that. I did lose about 10 pounds (unexplained) a few months ago, but after a couple months the weight came back plus a few pounds.