Brief Answer: Lymph nodes or abscess. Detailed Answer: Hello! Thank you for the query. Lumps under the armpit can be enlarged lymph nodes or an abscess due to hair follicle inflammation. If this lumps are painless, no redness, discharge, enlarged lymph nodes are most probable. Such lymph nodes can sometimes indicate breast cancer, that is why you should not ignore them. If this lumps are painful, skin is swollen, hair follicle inflammation and abscess formation are most probable. Especially if you have been shaving this armpit recently. I suggest you to consult a surgeon with this issue. Ultrasound should be done to determine what exactly it is. Hope this will help. Feel free to ask further questions. Regards.

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