Regional Cancer Center  JCMC

Johnson City Medical Center Cancer Specialists

The Regional Cancer Center at Johnson City focuses on evidence-based care provided by a multidisciplinary team. We work hard to prevent complications and provide the safest possible treatment. Our providers offer services using the latest in technology and treatment, including chemotherapy, radiation therapy, oncology surgery, clinical trials and genetic testing.

Dr. Kyle Colvett, Oncologist

Kyle Colvett, MD

Dr. Colvett received his medical degree from Quillen College of Medicine, East Tennessee State University.  He completed residency at Massachusetts General Hospital/Harvard University. Dr. Colvett is board-certified by American Board of Radiology and is a member of American Society for Therapeutic Radiology and OncologyAmerican Society of Clinical Oncology, Alpha Omega Alpha, American College of Radiation Oncology. He practices at the Regional Cancer Centers at Johnson City Medical Center and Indian Path Medical Center and at Franklin Woods Community Hospital.

Dr. Colvett serves as medical director for Johnson City Medical Center's Radiation Oncology program. He is clinical professor of surgery and internal medicine at Quillen College of Medicine. 

Dr. Kanishka Chakraborty, Oncologist

Kanishka Chakraborty, MD

Dr. Chakraborty received his medical degree from Calcutta Medical College.  He completed residency at East Tennessee State University and a fellowship at ETSU Quillen college of Medicine.

Dr. Mark Doherty, Oncologist  Mark Doherty, MD

Dr. Doherty received his medical degree from University of Vermont College of Medicine.  He completed residency at University of Pittsburgh Magee-Women's Hospital and fellowship at University of Texas Health Science Center M. D. Anderson Cancer Center. 

Dr. Doherty has been practicing and teaching cancer medicine/surgery for more than 25 years, and is a 21-year Navy veteran, serving in the Marine Corps for 19 of those years. He is trained in advanced laparoscopic surgery and robotic gynecologic oncology. He is married with four children and eight grandchildren, and enjoys outdoor sports and beautiful Tennessee.

Dr. Robert Enck, Oncologist

Robert Enck, MD

Dr. Enck received his medical degree from Hahnemann University Medical College in Philadephia, Pa., and completed his residency at Hahnemann Medical College and HospitalHe completed his fellowship at University of Rochester School of Medicine in New York. 

Dr. Enck is a professor of medicine at East Tennessee State University James H. Quillen School of Medicine in Johnson City, Tenn., and has contributed to multiple health care publications. 

Dr. Nathan Floyd, Oncologist 

Nathan Floyd, MD

Nathan Floyd received his medical degree from East Tennessee State University's Quillen College of Medicine.  He is a member of American Radium Society, American Society for Radiation Oncology and is board-certified by the American Board of Radiology.  His specialty is Radiation Oncology. 




Dr. Devapiran Jaishankar, Oncologist   

Devapiran Jaishankar, MD

Dr. Jaishankar received his medical school at Madras Medical college in India.  He completed his residency and a fellowship at East Tennessee State University's Quillen College of Medicine.  He is a member of American college of Physicians and board certified by the American Board of Internal Medicine.

Dr. Koyamangalath Krishnan, Oncologist

Koyamangalath Krishnan, MD

Dr. Krishnan received his medical degree from Kilpauk Medical College, University of Madras in India.  He completed his residency at East Tennessee State University and a fellowship at Michigan Medical School in Ann Arbor, Michigan.

Donette W Vicente, MD

Dr. Vicente received her medical degree from Stony Brook University School of Medicine.  She completed her residency, internship and a fellowship at Boston Medical Center.  She is a member of Rhode Island Medical Society, American Society of Clinical Oncology, American Society of Hematology and Massachusetts Medical Society. 

Dr. Vicente is board certified in general internal medicine and board eligible in hematology and medical oncology.
Melanie Harrison, PA

Melanie Harrison, PA

Ms. Harrison received her physician assistant degree from South University in Savannah, Ga. She completed her undergraduate degree at Lincoln Memorial University in Harrogate, Tenn. She is certified by the National Commission on Certification of Physician Assistants and is a member of the American Academy of Physician Assistants.

 Kim Pratt, ANP Kim Pratt, ANP

Ms. Pratt is a nurse practitioner certified in adult health.  She is a graduate of East Tennessee State University and received her nurse practitioner degree from Vanderbilt University School of Nursing.