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1.The possible cause could be infective lump which causing pain on touch and chest movements. Hair
follicle infection will be in the first place and then the infective collection /
abscess.
2.In this case i would have examined the patent and ask for an
ultrasound examination - which is investigation of choice.
3.Ultrasound will assess the nature of the lump its source and extensions.
4.In case of mass lesion an FNAC - fine needle aspiration cytology needed to assess the nature of the cells involved.
5.in case of infective collection, a small
incision and drainage followed by a course of antibiotics. good luck.
Hope i have answered your query,
any thing to ask do not hesitate to ask.
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