### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Hi! Ive got a bump in my left inguinal area which is oval in shape and about 2cm x 1 cm. The skin over the bump is very smooth and a bluish-grey hue with a black circular lesion in the middle which is only about 1mm in diameter. The skin over this black spot seems to be slightly rougher, but it is not ulcerating and I cant tell if its umbilicated.The bump first appeared over a year ago, maybe even two years, and I want to say that it began as an ulcerating erythematous pustular lesion (like a pimple, perhaps infected with staph) although its been awhile so I cant say for certain. Regardless, it has not been swollen or pruitic since the initial erythema resolved over a year ago. It really hasnt changed much during that time either. Its possible its gotten ever, ever so slightly larger, but I really cant say. It also seems as if that black spot at one time used to be deeper under the skin (but faintly visible) and is now at the surface as I mentioned earlier.I have no sexual history and my PMH is not significant for anything other than a benign parotid tumor about 7 years ago. Im a medical student spending my third year in a small community away from home and there arent really any physicians out here that Id feel comfortable showing/asking about it (since Im rotating with most of them). My biggest concern is that it could be a lymphoma or some other sort of cancer, but Im not certain about this presentation (namely the coloring).Thank you so much, I really appreciate it. Its something thats been concerning me for a while now.

### output:

Hello and welcome to Chat Doctor, An inguinal swelling occurs most commonly due to lymph node enlargement. The blue-black discoloration of the overlying skin with a black circular lesion can be due to infection or some kind of skin lesion. An aspiration cytology of the lesion is required. This investigation will sample the cells of the lesion. The cells are stained and examined microscopically. The origin and character of the lesion can be determined by examining the cells of the lesion. Lymph node enlargement can occur due to inflammation, lymphoma or a melanoma as suggested by black discoloration of the skin. Malignancy is accompanied by weakness, loss of appetite, and weight loss. A preceding history of infection of the urinary tract, lower limb can cause inflammatory enlargement of the inguinal lymph nodes. Thanks and take care Chat Doctor. 