this topic has been discussed, and the consensus is usually something to the effect of: if you desire patient contact that badly, strongly reconsider your decision to do pathology.
there are a lot of potential problems with a pathologist working in a free clinic as a generalist: staying current on medication regimens, physical exam skills, lack of internship, lack of DEA # to rx controlled substances. and there's probably more i'm not thinking of at the moment. it's a noble idea, one i've thought about myself, and the conclusion i usually reach is that the best way to help the underserved as a pathologist is to do their pathology for free or steeply discounted. work in a group practice? agree to read X pap smears from the local free clinic or health department without charging. or team up with a surgeon to read breast FNA/excisional biopsies. or team up with an endocrinologist to review thyroid tissue. my point is that you will be trained as a pathologist, not a clinician. i simply don't feel pathologists are able to adequately practice clinical medicine, and to do so is not only a huge legal liability for the doctor, but also a disservice to the patient, who should be seen by a clinical MD.