Peconic Surgical Group is a surgical practice in Riverhead that does many different surgical procedures. The physicians on staff at this practice are Leslaw J. Gredysa, M.D., George D. Keckeison, Agostino Cervone and Bogdan Makartchuk. Some of the many surgical procedures that Peconic does are Skin & Subcutaneous Tissue Procedures, Comprehensive Breast Surgeries, Lymphodectomy, Hernias, Vein Procedures, Hemorrodectomy, Sclerothropy and Venous Disease Screening and Treatment.