Duodenum lymphoma

Hello, I am new here and at a loss on how to proceed with helping my mom. She just received a dx of “Lymphoproliferative B cell disorder” with instruction to see oncologist, on a biopsy taken from duodenum mass. The endoscopy and colonoscopy were done to investigate severe lower bleeding episode. In addition to gi episode mom has been having fevers, fatigue and weight loss of 20lbs (135 to 115). She has had about 10 lumps on scalp with some crusted. Her pcp can’t see her for a week. I would like to get her scheduled with oncologist earlier if possible but don’t know how to find one well versed in this type of cancer, any suggestions! We are in Philadelphia. Thx;)