‘Do you know Interval cancers are more aggressive than mammography-detected cancers?’
According to a recent study published in a journal of the Cancer Research, ‘While the presence of common breast cancer mutations is indicative of increased breast cancer risk, certain rare mutations are indicative of increased risk of interval breast cancers and also leads to death.
A Senior Author Jingmei Li says…
Breast Cancer in woman
image courtesy-The Singapore Women’s Weekly
‘It is not just enough to know which markers can predict an increase in breast cancer risk, but also about the biomarkers that can identify the increased risk of aggressive interval cancers which are not usually detected during routine mammography screening.’
Interval Breast Cancer- An insight
Interval breast cancer is a term given to ‘cancers detection within 12 months after a mammographic screening’ in which findings are considered normal. The fact is that true negative interval cancers actually developed in the time period between the last mammogram which read as normal and the one on which the cancer was detected.
Number of Categories of Interval Breast Cancer!!
There are 5 types of interval breast cancer, such as-
1. True Negative Interval Cancer
There is no sign of disease may be detected on a previous screening mammogram and at later it is found.
2.Benign Interval Cancer
A lesion that proves to be malignant showed benign morphological characteristics.
3. Retrospectively visible interval cancer
A known lesion is seen on the previous screen mammogram which is an interpretive error on the part of the reader.
4. Single reader interval cancer:
A second reader would have discovered the lesion which yields up to 10% more cancers.
5. Technical failure interval cancer:
A technically poor image hampered the reader to discover if there any abnormality in the breast tissue or not.
How can Interval Breast Cancer be diagnosed?
‘About 20% of women who partake in routine mammography screening will be diagnosed with interval breast cancer.’
Li and colleagues analyzed data from over 5,000 breast cancer patients diagnosed between 2001 and 2008 and they found-
- Interval cancers are not identified through regular mammography screenings.
- So, the mode of detection for cancers driven by rare PTVs or common variants was performed.
- Additionally, the researchers developed a polygenic risk score (PRS) through the weighted sum is known common breast cancer variants, which was also correlated with tumor characteristics.
- As you know, dense tissue is one of the main reasons for developing tumors; women were stratified into risk categories based on percent breast density.
Interval Breast Cancer is more deadly – An understanding brief on it
The study shows that-
- A rare protein-truncating variants (PTVs) in 31 cancer predisposition genes, including BRCA1/2, is the main factor.
- Out of the 5,099 breast cancer patients, 597 of them are younger who carried PTVs and had more aggressive tumor phenotypes. They had 1.65 times the risk of death from breast cancer compared to those who did not carry PTVs.
- After excluding 92 women that carried mutations to BRCA1/2, women with PTVs had 1.76 times the risk of death from breast cancer compared to those without PTVs.
Another deep study
Women with low breast density who carried PTV mutations were 1.96 times as likely to be diagnosed with interval breast cancers compared to women who did not carry PTV mutations.
Further, those women carried non-BRCA1/2 PTV mutations still had 1.89 times increased risk compared to women who did not carry PTV mutations.
In contrast, women with low breast density and a higher PRS had a 23 % decreased risk for developing interval breast cancer.