HI,Dear -Kathleen.Very Good Morning from India.Thanks for your query.I understand your concerns.I studied your query in depth.
-I would advise you not to worry.In my opinion its -mostly a infective
lymphadenitis , as its far from the breast.If it would have been -CANCER REGROWTH-it would have been hard but painless-at the pea size stage,but being painful , its mostly infective lymphadenitis for SURE.
-Treatment-
a-I would advise-Tb-Antibiotic for 5 days time with Tb-NSAIDs,.The pain would go and swelling woulr reduce in 5 days time.
-b- If it persists and does not regress with Antibiotic treats-then FDG PET scan guided-FNAC
Biopsy of that LYmpnode would fix the cancerous nature of it.
-c-PET scan would also study the spread all over body- and would rule out the cancer fear and would relieve you.
-Oncosurgeon-consultation would be of lot of help to you.
-Hope this relieves your worry-some query. Wellcome for anymore queries in time to come.Have a Good Day.