Active — Not RecruitingNot Applicable

Radiotherapy Omission in Low Risk Ductal in Situ Carcinoma Breast

France295 participantsStarted 2019-05-10

Plain-language summary

Following breast-conserving surgery (BCS) for localized ductal carcinoma in situ (DCIS) of the breast, whole-breast irradiation (WBRT) is a standard of care, reducing the absolute rate of in-breast recurrences (IBR) by more than 15% at 10 years, from 28% without radiotherapy to 13 % with radiotherapy. Half of the recurrences occurred as invasive disease. Whereas in the comparative trials, WBRT did not impact on overall survival, survival of patients who recurred with invasive cancers was impaired in comparison to patients who did not recur, or to patients with DCIS-only recurrences. Using criteria based on age, tumor size, nuclear grade, and margins status, several trials and cohort studies failed to identify subgroups of patients at low risk, who could be safely spared the need for WBRT. The Radiation Therapy Oncology Group (RTOG) DCIS trial included patients treated with BCS for low- or intermediate grade DCIS revealed by unifocal microcalcifications, size ≤25 mm, margins ≥3 mm, and no residual microcalcifications after surgery. The 5-year rates of IBR were 3.5 % without radiotherapy, versus 0.4 % with radiotherapy, and 6.7 % and 0.9 % at 7 years, respectively (p \<0.001). Sixty percent of the patients received tamoxifen in both groups. Several studies showed that the same molecular classes were identified in DCIS as in invasive cancers. Studies suggested that low proliferation, hormone receptors expression, and lack of ERBB2 amplification were associated with a low risk of IBR in patients not receiving radiotherapy. A combined signature was tested in the Eastern Cooperative Oncology Group (ECOG) trial, showing a 10% IBR rate at ten years in patients with a low-risk. Identifying very low-risk DCIS, using biological markers in addition to the clinical and histological markers of low-risk DCIS, could help to select patients who could be safely avoided WBRT following BCS. It would avoid over-treatment in these women and could decrease the cost of management.

Who can participate

Age range50 Years

SexFEMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion criteria

✓. Woman aged ≥50 years,
✓. ECOG performance status ≤2
✓. Microcalcifications on pre-biopsy mammography, unifocal, ≤25 mm or opacity without microcalcifications and no clinical palpable tumour
✓. Absence of suspicious residual microcalcifications either on post-biopsy/ preoperative localization mammography, or on post-operative mammography Note: if absence of residual microcalcifications on post-biopsy/pre-operative mammography, post-operative mammography is not mandatory;
✓. Breast-conserving surgical excision;
✓. Histologically proven DCIS of the breast without an invasive component; Note Incidental histological finding of DCIS lesions developed within a benign breast lesion as well as an association with classical lobular carcinoma in situ (LCIS) associated with the DCIS are accepted.
✓. Free margins (≥2 mm), or free margins following re-excision;
✓. Low or Intermediate nuclear grade; Note: In case of nuclear grade heterogeneity within the same sample or between the biopsy or the surgical specimen, the highest nuclear grade score will prevail.

Exclusion criteria

What they're measuring

5-year cumulative incidence of in-breast cancer recurrences

Timeframe: 5 years

Trial details

NCT IDNCT03878342

SponsorUNICANCER

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2029-11-14

View on ClinicalTrials.gov More DCIS trials