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1.The history and location suggests there possible causes - hair follicular infection with collection, inguinal
hernia and finally
lymph nodal enlargement.
2.If you are my patient i would have examined the area and ask for an
ultrasound scan which is investigation of choice in this case.
3.The ultrasound will help assessing the nature of the lump its source and extensions. In case of mass lesion / lymph nodes - an FNAC - fine needle aspiration cytology to assess the cell type.
4.In case of hernia the defect size, contents and vascularity will be given by ultrasound.
5.So suggest you to see your GP and get examined,investigated and treated accordingly.
6.In case of infective collection a course of antibiotics will be helpful.
Hope i have answered your query,
any thing to ask do not hesitate to ask.
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