mas·tec·to·my | \ma-ˈstek-tə-mē \
plural mastectomies

Definition of mastectomy 

: surgical removal of all or part of the breast and sometimes associated lymph nodes and muscles

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Did You Know?

Breast cancer is the most common cancer among American women. Early cases can often be treated with drugs or with a small operation called a lumpectomy (because it removes a lump). Though a "simple mastectomy" is larger than a lumpectomy, it allows the breast to be reconstructed, using artificial implants or tissue from elsewhere on the body. But "radical mastectomy", which is required when the cancer is at an advanced stage, takes much of the chest muscle and makes reconstruction impossible.

Examples of mastectomy in a Sentence

Recent Examples on the Web

The latest case involves Judy Perkins, a 52-year-old structural engineer who lives in Port St. Lucie, Florida, and had a mastectomy after being diagnosed with very early stage breast cancer in 2003. Laurie Mcginley, ajc, "Researchers use immune-cell 'army' to battle another tough cancer," 4 June 2018 Phyllis Laccetti, a participant in the study, took the hormonal therapy tamoxifen alone for five years after having a mastectomy in 2007 to treat her breast cancer, even though her doctor’s initial recommendation was to also receive chemotherapy. Peter Loftus, WSJ, "Doctors Suggest Less Chemo, Surgery for Some Cancer Treatments," 3 June 2018 In the majority of cases, women who undergo mastectomy also opt for implant reconstruction, and women who undergo salpingo-oophorectomy begin taking synthetic hormone replacement therapy. Katherine Drabiak, Washington Post, "As more women turn to genetic testing for breast cancer, understanding risk is key," 25 June 2018 Such women usually have surgery — mastectomy or a lumpectomy and radiation — followed by years of a hormone-blocking drug aimed at keeping cancer from returning. Marie Mccullough,, "What the latest news on breast cancer, chemo and genomic testing could mean for you," 5 June 2018 Mall underwent a double mastectomy and received hormone treatments, but decided not to go through chemotherapy after discussing the uncertainty of its effectiveness with Albain. Vikki Ortiz,, "New breast cancer research to spare thousands of patients from chemotherapy," 3 June 2018 Thankfully, after undergoing a double mastectomy, reconstructive surgery, and months of chemotherapy, Dana came out on top. Kayla Keegan, Redbook, "This Woman Got Tattoos After Breast Cancer To Take Back Her Body," 15 Oct. 2015 The 61-year-old had a mastectomy of her left breast in 2017 and is undergoing daily radiation treatments until mid-July. Darcel Rockett,, "'If I lived on the North Side': Neighborhood may matter more than race in breast cancer survival rates," 9 July 2018 Two years ago, she was diagnosed with breast cancer, which required a mastectomy., "Release programs for sick and elderly prisoners could save millions. But states rarely use them.," 18 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mastectomy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mastectomy

circa 1923, in the meaning defined above

History and Etymology for mastectomy

Greek mastos breast + English -ectomy

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mast brown

mast cell




master's deed

Statistics for mastectomy

Last Updated

30 Sep 2018

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Time Traveler for mastectomy

The first known use of mastectomy was circa 1923

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More Definitions for mastectomy


mas·tec·to·my | \ma-ˈstek-tə-mē \
plural mastectomies

Medical Definition of mastectomy 

: surgical removal of all or part of the breast and sometimes associated lymph nodes and muscles — see modified radical mastectomy, partial mastectomy, radical mastectomy, simple mastectomy

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