Donald R. Lannin, MD


General Surgery, Surgical Oncology

Conditions & Treatments

Breast Biopsy, Breast Cancer, Breast Cancer Surgery, Breast Disease, Breast Surgery, Cancer, Ductal Lavage, Ductoscopy, Lumpectomy, Lymph Node Biopsy, Mastectomy Reconstruction, Oncology Surgery, Sentinel Lymph Node Biopsy

(203) 200-2328
Accepting New Patients
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Donald Lannin, MD, is a surgical oncologist and breast cancer specialist with more than 30 years of experience. He was instrumental in building the Breast Center at Smilow Cancer Hospital at Yale New Haven, and served as executive director of the Yale Breast Center before Smilow Cancer Hospital opened in 2010.

Dr. Lannin is an especially warm and caring breast surgeon. In his years of treating patients who must manage an emotional diagnosis, he says he has learned to “be honest and sympathetic.” It’s important to involve other caregivers, including nurses and social workers, to provide proper support, he says.

He likes to remind people that patients who are diagnosed and treated before the disease has a chance to progress usually have good outcomes and move on with their lives. However, he also stresses that early diagnosis is an area doctors are learning more about—in 2017, Dr. Lannin was lead author of a Yale Cancer Center study published in the New England Journal of Medicine that showed that the diagnosis of small breast cancer tumors may be overrated, because many small tumors grow so slowly that their early detection does not increase survival rates. “Having this knowledge is helping us avoid the major harms of overdiagnosis, which can result in overtreatment, not to mention extra anxiety and fear for patients,” Dr. Lannin says.

A professor of surgical oncology at Yale School of Medicine, Dr. Lannin was formerly the director of the Leo Jenkins Cancer Center at East Carolina University. He has been recognized on lists of best doctors in the region and with such honors as the American Cancer Society Sword of Hope Award.






Years In Practice


Affiliated With

Yale Medicine


Education & Training


University of Minnesota


University of Minnesota Hospitals


NIH National Research

Accepted Insurance

Insurance coverage regularly changes, please contact the doctor’s office directly to verify that your specific insurance plan is accepted.

  • aetna
  • anthem bc/bs
  • berkeley care network
  • cigna healthcare
  • community care network
  • connecticare
  • corvel
  • first health network
  • focus healthcare
  • great west
  • husky
  • medicaid
  • medicare
  • multiplan
  • oxford health plans
  • railroad medicare
  • tricare/champus
  • united healthcare
  • us family health plan
  • wellcare