Peconic Surgical Group was established in 1994 by Dr. Leslaw Gredysa. Since the beginning, the goal for the practice was to provide excellent and compassionate surgical care to those in need on eastern Long Island. The practice was joined by Dr. George Keckeisen in 1997, Dr. Agostino Cervone in 1999.

The surgeons at Peconic Surgical Group are highly trained and qualified individuals whom have completed their residences in general surgery at prestigious programs throughout the United States. In addition, Dr. Gredysa and Dr. Keckeisen have completed vascular fellowships, Dr.Gredysa at St. Francis Hospital and Heart Center at Roslyn on Long Island and Dr. Keckeisen at Westchester County Medical Center, New York. All practice doctors are Board Certified.