News | PET Imaging | March 18, 2019

PET Scans Show Biomarkers Could Spare Some Breast Cancer Patients from Chemotherapy

De-escalation of treatment strategies aims to minimize toxicity while maintaining efficacy

PET Scans Show Biomarkers Could Spare Some Breast Cancer Patients from Chemotherapy

March 18, 2019 — A new study of positron emission tomography (PET) scans has identified a biomarker that may accurately predict which patients with one type of HER2-positive breast cancer might best benefit from standalone HER2-targeted agents, without the need for standard chemotherapy. The study was conducted by researchers at the Johns Hopkins Kimmel Cancer Center in an effort to further individualize therapy and avoid over-treating patients.

An estimated 1 in 5 women with breast cancer have a mutation in their tumor cells that produces excess amounts of human epidermal growth factor receptor 2 (HER2), a protein that promotes cancer growth.

“Although further studies are needed before the PET scan biomarker can be reliably used on a wide scale, the results of this study have the potential to advance the options for precision medicine in women with breast cancer,” said Vered Stearns, M.D., professor of oncology, co-director of the Breast and Ovarian Cancer Program at Johns Hopkins and senior author of the manuscript published in the February 2019 issue of Journal of Clinical Oncology.1 “This study, coupled with other complete and ongoing investigations at the Breast and Ovarian Cancer Program at Johns Hopkins, is at the forefront of providing true precision medicine to patients with breast cancer.”

For the study, investigators fully evaluated 83 of 88 women with stage II or stage III estrogen receptor (ER)-negative, HER2-positive breast cancer recruited from nine Translational Breast Cancer Research Consortium (TBCRC) medical facilities across the United States, including The Johns Hopkins Hospital.

PET scans that use radioactive tracers to detect sugar uptake in cancer cells were conducted prior to and 15 days after patients were given the first of four cycles of pertuzumab and trastuzumab (without chemotherapy) over a 12-week period. Those two drugs are monoclonal antibodies that precisely target particular proteins on HER2-positive cancer cells and are widely used to treat HER2-positive breast cancers, usually in combination with chemotherapy drugs that poison such cells and carry more toxic side effects.

The researchers sought to evaluate whether early changes on a PET scan — images taken during the first stages of targeted therapy — can help determine whose tumor will disappear completely following HER2-targeted treatment.

After two weeks of treatment, researchers found they could predict whether a patient would respond to HER2-targeted treatment without chemotherapy. In approximately 56 percent of cases (44 patients), a predictive biomarker was identified that could have the potential to be a useful early response assessment tool.

Lead author Roisin Connolly, M.B.B.Ch., M.D., associate professor of oncology at the Kimmel Cancer Center, said the change in sugar uptake on PET scans from baseline to two weeks after starting treatment, and the value at the two-week time point itself, had the best ability to predict response to HER2-directed therapy with high sensitivity and very high negative predictive value. High sugar levels two weeks after treatment, said Connolly, indicate the tumor likely will not fully respond to antibodies alone and will need chemotherapy.

She said there is great interest at this time in “de-escalation” of treatment strategies in breast cancer, which aim to minimize toxicity while maintaining the efficacy.

“Based on our findings, if the sugar uptake shown on the scans is below a certain level at two weeks, antibody therapy may be enough to induce a complete response, and those patients may be spared the toxic effects of chemotherapy.”

ER-negative, HER2-positive breast cancer accounts for about 8 percent of all breast cancers. Standard treatment calls for a combination approach of surgery to remove the bulk of the tumor, and a combination of antibody therapy to cut off the ability of the HER2 gene to support the growth of breast cancer cells and chemotherapy to directly kill the cancer cells.

“So in the future, we may be able to offer this as a chemo-free approach. Further research is still required to investigate this before it can become standard practice in the clinic to make treatment decisions, but it is extremely promising,” Connolly said.

The 88 women enrolled in the study were treated between January 2014 and August 2017, and 83 were evaluated for the primary study. All four cycles of targeted therapy drugs were completed in 85 percent of cases (75/88), and all 83 patients who completed follow-up had surgery after the therapy.

For more information: www.ascopubs.org/journal/jco

 

Reference

1. Connolly R.M., Leal J.P., Solnes L., et al. TBCRC026: Phase II Trial Correlating Standardized Uptake Value With Pathologic Complete Response to Pertuzumab and Trastuzumab in Breast Cancer. Journal of Clinical Oncology, Feb. 5, 2019. https://doi.org/10.1200/JCO.2018.78.7986

Related Content

SIR-Spheres Y-90 resin

SIR-Spheres Y-90 resin microspheres are released into the hepatic artery.

News | Nuclear Imaging | February 14, 2020
February 14, 2020 —  ...
Nuclear imaging equipment growth in 2020
News | Nuclear Imaging | February 14, 2020
February 14, 2020 — The nuclear imaging equipment
Mammograms of a 49-year-old woman with invasive lobular carcinoma on the right-side breast

Mammograms of a 49-year-old woman with invasive lobular carcinoma on the right-side breast. A small mass with micro-calcifications on the right-side breast was detected correctly by AI with an abnormality score of 96%. This case was recalled by 7 out of 14 radiologists (4 breast radiologists and 3 general radiologists) initially (without AI) and all 14 radiologists recalled this case correctly with the assistance of AI.

News | Artificial Intelligence | February 11, 2020
February 11, 2020 — A new study, published in...
Accuray TomoTherapy total body irradiation
News | Radiation Therapy | February 07, 2020
February 7, 2020 — Accuray Incorporated announced that two new studies demonstrate the benefits of the ...
Sponsored Content | Videos | Artificial Intelligence | February 06, 2020
ProFound AI is an FDA-cleared artificial intelligence (AI) system for reading 3-D breast tomosynthesis images.
Feature | Breast Imaging | February 03, 2020 | By Barbara Smith
Women in the United States have a 1 in 8 (or about 13 percent) lifetime risk of being diagnosed with breast cancer du
News | Clinical Trials | February 03, 2020
February 3, 2020 — Melding the genetic and cellular analysis of tumors with how they appear in medical images could g
Automated Triage of Thyroid Cancer

73-year-old man with papillary carcinoma of left lobe of thyroid. Screen shot shows example of thyroid nodule annotation (segmentation and TI-RADS annotation) performed on ultrasound image in longitudinal projection with electronic Physician Annotation Device software (Stanford Medicine Radiology). Radiologists performed nodule segmentation by selecting points (red) on nodule outline (green), while controlling smoothing of outline polygon by means of spline interpolation.

News | Ultrasound Imaging | January 30, 2020
January 30, 2020 — According to an ar...
ringing the cancer bell can do more harm than good, says an ASTRO study

Image courtesy of ASTRO

News | Radiation Oncology | January 27, 2020
January 27, 2020 — It's a scene that some cancer patients dream about: they celebrate the end of a course of radiatio