Maggie Smith, Breast Cancer, and Working Through Treatment

"I didn't think it was anything serious"

Dame Maggie Smith was diagnosed with breast cancer while filming Harry Potter and the Half-Blood Prince. TODAY reports that she went through chemotherapy and radiation over about two years, and was then declared cancer free.

She was blunt about all of it in an interview with The Times. On finding the lump, she said: "I had been feeling a little rum. I didn't think it was anything serious because years ago I felt a lump and it was benign." On the treatment, she said it was "hideous," adding: "You feel horribly sick. I was holding on to railings, thinking, 'I can't do this.'" On filming through it, she said, "I was hairless ... I was like a boiled egg." She wore a wig on set and finished the last two Harry Potter films.

She died on Friday, September 27, 2024, in a London hospital, at the age of 89. No cause of death was disclosed, and this page will not speculate about one.

Her first sentence is the one worth building on, because a previous benign lump told her nothing whatsoever about this one.

Why old results do not clear new lumps

Breast tissue produces lumps for many reasons, and most of them are not cancer, since cysts, fibroadenomas, and hormonal changes all make lumps that come and go.

That history is exactly why a new lump still requires evaluation. The old lump was assessed and found benign, whereas the new one has not been assessed at all, and no amount of past reassurance substitutes for that.

CDC makes the same point from the other side: the warning signs of breast cancer "can happen with other conditions that are not cancer," and the response is still to see a doctor promptly.

When to get checked

CDC lists these warning signs. Any one of them warrants an appointment now, not at your next routine visit.

• A new lump in the breast or in the armpit
• Thickening or swelling in part of the breast
• Skin that is dimpled, irritated, red, or flaky over the breast or nipple
• A nipple that starts turning inward, or pain in the nipple area
• Nipple discharge other than breast milk, including blood
• Any change in the size or the shape of the breast
• Pain in any area of the breast

Screening runs on its own schedule. CDC states the U.S. Preventive Services Task Force recommendation that women aged 40 to 74 at average risk get a mammogram every two years, and notes that different schedules may apply to women at higher risk.

What the biopsy decides

Diagnosis follows a set order, and the National Cancer Institute's clinician guidance lists "mammography, ultrasonography, breast magnetic resonance imaging (MRI), if clinically indicated" and then biopsy. Imaging raises the question, and only tissue answers it.

Three results on that pathology report drive everything after. NCI names estrogen receptor status, progesterone receptor status, and HER2 status among the features that determine treatment, alongside stage, tumor grade, and menopausal status.

Receptors are docking sites on the cancer cell, and NCI states that estrogen receptor status is measured mainly by immunohistochemistry, a stain applied to the tissue, where "any staining of 1% of cells or more is considered positive." HER2, a growth-signaling protein, is measured by that same stain or by counting gene copies. Hormone receptor positive cancers can be treated with drugs that block estrogen, and HER2 positive cancers with drugs aimed at HER2.

What chemotherapy is doing to you

NCI's explanation is short and it explains almost every side effect at once. "Chemotherapy works by killing or stopping the growth of cancer and other fast-growing cells." The trouble is that some healthy cells are fast-growing too.

NCI spells out which ones: cells lining the mouth and intestines, and the cells that grow hair, which is where mouth sores, nausea, and hair loss come from. NCI adds that "the most common side effect is fatigue."

Chemotherapy is usually given in cycles, with treatment followed by a recovery gap, and NCI gives an example of a week of treatment followed by three weeks off. The schedule depends on the cancer, the drugs, the goal, and how the body responds.

Radiation, and what it feels like

Radiation works differently. NCI states that it "kills cancer cells or slows their growth by damaging their DNA," and that it "takes days or weeks of treatment before DNA is damaged enough for cancer cells to die." That is why it is delivered in many small doses rather than one large one.

External beam radiation comes from a machine outside the body, while internal radiation places a source inside, either solid, called brachytherapy, or liquid. NCI notes that radiation also affects nearby healthy cells, which is where the side effects come from, and it names fatigue among them. NCI also points out that cancer cells keep dying for weeks or months after the last session, so finishing treatment is not the same moment as feeling better.

Working through it

Smith kept filming. That is possible for many people, and NCI says so plainly: "many people can work during chemotherapy, as long as they match their work schedule to how they feel."

NCI notes that part-time or remote arrangements can help, and that employers are often required by law to adjust a schedule to meet a patient's needs. In the United States that points toward workplace accommodation rules, which are worth asking about before treatment starts rather than after a bad week.

It is also worth saying that working through treatment is not a test anyone has to pass, because some regimens and some jobs make it impossible, and that has nothing to do with resolve.

The population numbers

For 2026 the American Cancer Society projects 321,910 new cases of female breast cancer and 42,140 deaths in the United States. SEER, the National Cancer Institute's surveillance program, reports that projection along with the measured figures that follow. The median age at diagnosis is 64, and the rate of new cases is 132.5 per 100,000 women per year.

Five-year relative survival across all stages is 91.9 percent, based on cases from 2016 through 2022. By stage, within that same 2016 to 2022 group, SEER lists 100.0 percent for localized disease, 87.5 percent when nearby nodes are involved, and 33.8 percent once the cancer has reached distant organs. Sixty-four percent of those cases were found while still localized.

Relative survival compares people with the diagnosis to people of the same age without it. These are group figures built from hundreds of thousands of records, and they do not forecast one person's course.

Sources

• https://www.today.com/health/maggie-smith-health-rcna173011
• https://www.cancer.gov/types/breast/hp/breast-treatment-pdq
• https://www.cancer.gov/about-cancer/treatment/types/chemotherapy
• https://www.cancer.gov/about-cancer/treatment/types/radiation-therapy
• https://seer.cancer.gov/statfacts/html/breast.html
• https://www.cdc.gov/breast-cancer/symptoms/index.html
• https://www.cdc.gov/breast-cancer/screening/index.html