Breast cancer surgery clinicians in Portland, Oregon
CMS lists 21 clinicians with a primary specialty of General Surgery or Surgical Oncology who have billed Medicare for at least one mastectomy procedure and practice in Portland, Oregon (details below).
Breast cancer surgery volume
| Clinician | Mastectomy procedures billed | Percentile rank |
|---|---|---|
| Sarah Walcott Sapp, MD | 64 | 95% |
| Kristen Massimino, MD | 61 | 94% |
| Cory Donovan, MD | 38 | 86% |
| Kathleen Dunham, MD | 34 | 83% |
| Toni Storm Dickerson, MD | 33 | 83% |
| Arpana Naik, MD | 32 | 82% |
| James Imatani, MD | 28 | 79% |
| Nathalie Johnson, MD | 23 | 74% |
| Shaghayegh Aliabadi, MD | 20 | 71% |
| Jennifer Garreau, MD | 20 | 71% |
| Hannah Kornfeld, MD | 17 | 67% |
| Frances Ting, MD | 17 | 67% |
| Alivia Cetas, MD | 11 | 58% |
| Violetta De La Melena, MD | 1-10 | 58% or below |
| Benjamin Feeney, MD | 1-10 | 58% or below |
| Chelsea Hardin, MD | 1-10 | 58% or below |
| Lauren Orr, MD | 1-10 | 58% or below |
| Rodney Pommier, MD | 1-10 | 58% or below |
| John Vetto, MD | 1-10 | 58% or below |
| Rachel Warren, MD | 1-10 | 58% or below |
| Karen Zink, MD | 1-10 | 58% or below |
Sorted by the number of mastectomy procedures billed to Medicare, highest first, not by quality or skill. CMS suppresses counts between 1 and 10 to protect patient privacy and publishes the range instead.
Understanding CMS Data
CMS's "Mastectomy" category combines specific billing codes for breast surgery to calculate the number of times each clinician billed Medicare for a "Mastectomy." These include partial removal of the breast (lumpectomy); removal of the whole breast, with or without underarm lymph nodes; breast reconstruction after mastectomy; implant and implant-capsule procedures; breast lift and reduction; placement of a radiation device during surgery; and surgery for enlarged male breast tissue. CMS reports only procedures that clinicians billed to Original Medicare and Medicare Advantage. Therefore, CMS's procedure volume data does not include procedures that clinicians may have performed on patients who have other health care coverage (e.g., commercial insurance, self-pay, or the VA). Billing variation and coding errors can also affect CMS's data. Therefore, the number of procedures that CMS reports for a clinician may be higher or lower than the actual number of mastectomy procedures a clinician performed during the reporting period. Lastly, only clinicians with a primary specialty of General Surgery or Surgical Oncology (as reported to Medicare) are presented.
Source: Centers for Medicare & Medicaid Services (August 18, 2026 release).