News | Radiation Therapy | April 22, 2021

New Study Reveals Targeted Therapy Working in Early Breast Cancer

A Norwegian study for the first time reveals benefit of the PARP inhibitor Olaparib in patients with early breast cancer not harboring germline mutations

 

A Norwegian study for the first time reveals benefit of the #PARP inhibitor #Olaparib in patients with early #breastcancer not harboring germline mutations

Getty Images

April 22, 2021 — Targeted therapy in early stages of breast cancer can pave the way for a notable higher success rate, shows a study from the University of Bergen, Norway (UiB).

PARP (Poly (ADP-ribose) polymerase) inhibitors represent an established targeted therapy for multiple cancer types, including cancers of the prostate, ovary and rare cases of breast cancer.

PARP inhibitors take advantage of defects in a central mechanism of DNA damage repair, observed in these cancers. While such compounds have been successfully applied in ovarian and prostate cancers, to this end only a small minority of patients with breast cancer (2-3%), harboring germline mutations in the BReast CAncer type-1 and -2 (BRCA1/2) genes have benefitted, and a seminal study conducted 12 years ago reveled no benefit for patients with breast cancer not harboring such mutations.

Now, a national Norwegian study headed by professors Hans Petter Eikesdal, Stian Knappskog and Per Eystein Lønning at University of Bergen and Haukeland University Hospital for the first time reveals benefit of the PARP inhibitor Olaparib in patients with early breast cancer not harboring germline mutations.

Poor prognosis — considerable results

In the PETREMAC study, unselected patients with large (>4 cm diameter) so-called triple negative breast cancers were treated upfront with Olaparib.

Triple negative breast cancers is a breast cancer subgroup often affecting young patients and is a form of breast cancer associated with a poor prognosis.

Among 32 patients treated, 18 (56%) responded with tumor regression on Olaparib monotherapy. Most importantly, 16 out of the 18 responders revealed molecular markers predicting a likely benefit (gene mutations or so-called epigenetic modifications) of genes involved in the process of DNA repair contrasting only 4 out of 14 non-responders.

These findings allow identification of individual tumors likely to benefit from PARP inhibition. Five patients harbored germline mutations (i.e. patients that may potentially be treated with a PARP inhibitor prior to this study).

However, among patients not harboring such germline mutations (i.e. patients that would normally be excluded from PARP inhibitor therapy), 14/26 patients (54%) responded to therapy. Moreover, among these 14 patients, 12 could be identified upfront as likely responders based on analyzing their tumor tissue for mutations / epimutations affecting DNA repair.

Improved personalized treatment

In conclusion, the study challenges the previous dogma that PARP inhibition may not work for patients not harboring germline mutations. Most importantly, the authors found a strong correlation between response to therapy and molecular markers easily detectable in the tumor tissue.

"While the results need confirmation in independent studies, our results point toward improved personalized treatment for many patients diagnosed with triple negative breast cancer", says professor Lønning.

Finally, the study illuminates a concept gaining increasing support in oncology: While previous studies revealed no benefit from PARP inhibition in late-stage breast cancer, this study demonstrates a therapy which was ineffective in late cancer may potentially be of great benefit in the early setting.

For more information: www.uib.no/

Related Content

Volpara Health, a global health technology software leader providing an integrated breast care platform for the delivery of personalized breast care, has signed an agreement with Invitae Corporation, a leader in medical genetics, to bring Invitae's genetic testing services to Volpara's customers in the United States. 
News | Breast Imaging | July 29, 2021
July 29, 2021 — Volpara Health, a global health technology software leader providing an...
The FLASH Effect significantly improves the therapeutic ratio for curing cancer

The FLASH Effect significantly improves the therapeutic ratio for curing cancer

News | Radiation Oncology | July 28, 2021
July 28, 2021 — IntraOp Medical Corporation announced that ...
Recommendations address when and how radiation therapy should be used and outline best practices for patient-centered care

Figure 1. The guideline also includes treatment algorithms for initial local management (Figure 1) and local management following an unplanned excision (Figure 2).

News | Radiation Therapy | July 27, 2021
July 27, 2021 — A ...
Radiation oncologists urged Congress to reverse proposed CMS cuts and create more equity in access to cancer treatments

Getty Images

News | Radiation Oncology | July 26, 2021
July 26, 2021 — A record number of radiation oncologists met with Congressional leaders and staff last week as part o
The 15-ton compact accelerator is lifted into the David C. Pratt Cancer Center at Mercy St. Louis. (Photo: Business Wire)

The 15-ton compact accelerator is lifted into the David C. Pratt Cancer Center at Mercy St. Louis. (Photo: Business Wire)

News | Radiation Oncology | July 21, 2021
July 23, 2021 — Mevion Medical Systems announced that it has delivered the 15-ton compact accelerator to...
Registration is now open for the Radiological Society of North America (RSNA) 107th Scientific Assembly and Annual Meeting, the world’s largest annual radiology forum, to be held at McCormick Place Chicago, Nov. 28 – Dec. 2, 2021

Getty Images

News | RSNA | July 21, 2021
July 21, 2021 — Registration is now open for the Radiological Society of North America (...
ASTRO just issued the following statement in response to the Radiation Oncology Model update in yesterday's HOPPS proposed rule, which compounds significant and detrimental cuts to the cancer care specialty in the proposed 2022 MPFS

Getty Images

News | Radiation Therapy | July 20, 2021
July 20, 2021 — In response to consecutive weeks of proposed...
Artificial intelligence-powered diagnostic tool spots asymptomatic prostate cancer in seconds

(L-R) Associate Professor Peter Brotchie (St Vincent's), Dr Ruwan Tennakoon (RMIT), Professor John Thangarajah (RMIT), Dr Mark Page (St Vincent's). Image courtesy of St Vincent's Hospital Melbourne

News | Prostate Cancer | July 19, 2021
July 19, 2021 — Prostate cancer is the most diagnosed
According to ARRS’ American Journal of Roentgenology (AJR), return to routine screening for BI-RADS 3 lesions on supplemental automated whole-breast US (ABUS) substantially reduces the recall rate, while being unlikely to result in adverse outcome

Normal right mediolateral oblique (A) and craniocarudal (B) view screening mammograms demonstrate density C breasts. Coronal (C), transverse (D), and reconstructed lateral (E) views from supplemental automatic breast ultrasound (ABUS) demonstrates 7 mm circumscribed slightly hypoechoic circumscribed lesion at 11 o’clock position in right breast. Lesion was classified as BI-RADS 3. Patient has undergone yearly mammograms for 4 years following the ABUS examination with no breast cancer diagnosis.

News | Breast Imaging | July 16, 2021
July 16, 2021 —...