PET/CT Scans May Clarify Staging for Certain Young Women

A study of young women diagnosed with stage I-III breast cancer using traditional staging methods found that later PET/CT scans changed 21 percent of those diagnoses to stage III or IV.

Background and Goals

PET/CT scans take images of the inside of the body using a combination of PET, positron-emission tomography, and CT, computed tomography. National Comprehensive Cancer Network guidelines recommend the scans only as an option for those with stage III breast cancer, or when initial tests are unclear. Doctors have debated whether factors such as age or disease subtype should be considered for using PET/CT in staging breast cancer.

Traditional staging depends on physical exams, mammograms, ultrasound and MRI, magnetic resonance imaging. PET/CT shows if a change or abnormality is likely to represent breast cancer spread. A PET/CT scan may result in a diagnosis being upstaged, or changed to a higher stage than first given.

Some doctors think traditional staging may miss metastatic disease in young women that PET/CT could detect. Knowing the correct disease stage before treatment begins helps in choosing the best therapies.

This study looked at PET/CT staging in young women with stage I-III breast cancer and how often stages changed in different subtypes.

Design

Information on women diagnosed with stage I-III breast cancer from 2003 to 2012 was drawn from a large cancer center database. All were younger than 40 when diagnosed and had PET/CT staging after traditional staging. They were compared to a similar group of women who did not have PET/CT staging.

Results

The study included 134 women aged 22.2 to 39.9 years. They received PET/CT a median of 21.5 days after initial diagnosis.

In 28 women, or 21 percent, PET/CT scans identified disease spread to lymph nodes, metastases beyond the breast area, or both, that had not been detected during traditional staging. Eight women had lymph-node spread only.

Upstaging to stage IV, or metastatic breast cancer, occurred in

• 1 of 20 (5 percent) initially diagnosed stage I
• 2 of 44 (5 percent) initially diagnosed stage IIA
• 8 of 47 (17 percent) initially diagnosed stage IIB
• 4 of 13 (31 percent) initially diagnosed stage IIIA
• 4 of 8 (50 percent) initially diagnosed stage IIIB
• 1 of 2 (50 percent) initially diagnosed stage IIIC

PET/CT scans showed 10 percent of women with initial stage I or II disease actually had stage IV.

Among all who were upstaged, no significant relationship was found to race, tumor grade or cancer subtype.

Although current guidelines do not recommend PET/CT staging for stage II disease and consider it optional for stage III, the researchers say the data suggests benefit for young women, even at stage IIB. They also suggest a prospectivestudy, in which participants are followed, to verify these findings.

Limitations

This study looked at only a small group of women from a single cancer center. The results may differ in a larger group from a diverse database. Also, it is not clear from the study if upstaging changes survival. Randomized, controlled prospective studies could determine that.

What This Means For You

Breast cancer stage is important for guiding treatment choices. As technology develops, research is looking at ways to make staging more accurate.

You may be concerned and wonder if the staging you received is correct. Keep in mind that this study was relatively small and looked back at test results. More studies are needed to see if current guidelines for PET/CT staging will be changed.

If you have questions, talk with your doctor about what your tests showed. For those who are newly diagnosed, discuss whether this study’s results mean PET/CT staging might be helpful for you. You also can talk confidentially with someone who understands and cares through the LBBC Breast Cancer Helpline, (888) 753-LBBC (5222).

Riedl, CC, Slobod, E, Jochelson, M, et al.  Retrospective Analysis of 18F-FDG PET/CT for Staging Asymptomatic Breast Cancer Patients Younger Than 40 Years. J Nucl Med. 2014; doi: 10.2967/jnumed.114.143297.