Dr. Lerwill is co-director of the Breast Pathology Service at Massachusetts General Hospital. She lectures in graduate medical education courses in the United States and abroad.



Centers & Specialties

Cancer Center

Clinical Interests
  • Breast pathology
  • Gynecologic pathology
Medical Education
  • MD, Harvard Medical School
  • Residency, Massachusetts General Hospital
Board Certifications
  • Anatomic Pathology
  • Pathology
  • Boston: Massachusetts General Hospital
Insurances Accepted
  • Aetna Health Inc.
  • Beech Street
  • Blue Cross Blue Shield - Blue Care 65
  • Blue Cross Blue Shield - Indemnity
  • Blue Cross Blue Shield - Managed Care
  • Blue Cross Blue Shield - Partners Plus
  • Cigna (PAL #'s)
  • Fallon Community HealthCare
  • Great-West Healthcare (formally One Health Plan)
  • Harvard Pilgrim Health Plan - PBO
  • Health Care Value Management (HCVM)
  • Humana/Choice Care PPO
  • MassHealth
  • Medicare
  • Medicare - ACD
  • Neighborhood Health Plan - ACD
  • Neighborhood Health Plan - PBO
  • OSW - Maine
  • OSW - New Hampshire
  • OSW - Rhode Island
  • Private Health Care Systems (PHCS)
  • Railroad Medicare
  • Railroad Medicare - ACD
  • Senior Whole Health
  • TriCare
  • Tufts Health Plan
  • Unicare
  • United Healthcare (non-HMO) - ACD
  • United Healthcare (non-HMO) - PBO

Note: This provider may accept more insurance plans than shown; please call the practice to find out if your plan is accepted.

Patient Age Group


Dr. Lerwill received her medical degree from Harvard Medical School. She completed her residency in anatomic pathology and a fellowship in breast and gynecologic pathology at Massachusetts General Hospital. Her main research interests include early neoplasia of the breast, biphasic tumors of the breast, use of immunohistochemistry in diagnostic breast pathology, and metastatic lesions to the gynecological tract. Her academic work focuses on practical aspects of diagnostic breast and gynecologic pathology, and she is a frequent speaker at pathology postgraduate courses.

Research & Publications

Research Summary

Current areas of clinicopathologic investigation include:

  • Early epithelial neoplasia of the breast

  • Phyllodes tumors and other biphasic lesions of the breast

  • Use of immunohistochemistry as a diagnostic aid in breast pathology

  • Metastatic tumors to the ovary


View my most recent publications at PubMed


Pathology Associates
55 Fruit Street
Boston, MA 02114-2696
Phone: 617-726-2967
Fax: 617-726-7474