Understanding Oncogenic Mutations in Cancer

Oncogenic mutations are changes in our DNA that can cause cancer. Knowing about these mutations is really important for figuring out how to diagnose and treat cancer. Over the years, scientists have developed many new methods to find these mutations.

1. Ways to Detect Mutations

A. Polymerase Chain Reaction (PCR)

• PCR helps make many copies of a specific part of DNA.
• This makes it easier to look for changes in genes.
• It can find mutations in about 1 out of every 10,000 cells.

B. Next-Generation Sequencing (NGS)

• NGS lets us look at many genes at the same time, giving us a bigger picture of genetic changes.
• Research shows that NGS can find 50-80% of important mutations in different types of cancer.

C. Sanger Sequencing

• This older method is still useful for double-checking specific mutations found using other techniques.
• It's especially good for looking at smaller DNA segments.
• Sanger sequencing is very accurate, with more than a 99% success rate.

D. Fluorescence In Situ Hybridization (FISH)

• FISH helps spot problems in chromosomes related to cancer genes.
• For example, it can find the HER2 gene boost in breast cancer, which happens in about 20-30% of cases.

2. Getting Diagnosed

A. Liquid Biopsies

• These tests look at pieces of tumor DNA found in the blood, so doctors don't need a sample from the tumor itself.
• They are showing good results, finding important mutations in about 70% of cases.

B. Immunohistochemistry (IHC)

• IHC checks the levels of certain proteins linked to cancer genes, giving us information about mutations.
• About 30-40% of breast cancer cases have too much of the ERBB2 gene, which can guide treatment choices.

3. How This Affects Treatment

A. Targeted Therapies

• Discovering specific oncogenic mutations allows doctors to choose treatments that fit a patient’s needs.
• For instance, about 60% of lung adenocarcinomas have mutations in the EGFR gene, and there are special medicines that can target these.

B. Prognostic Information

• Genetic testing can also tell us how likely a patient is to do well.
• For example, people with mutations in the TP53 gene often have a worse outlook, as their chances of survival are lower than those without these mutations.

4. Key Facts and Trends

• Around 30% of all cancers are connected to known oncogenic mutations.
• Studies show that targeted treatments can improve survival rates in people with these mutations by about 30-50%.
• As of 2023, there are about 60 targeted therapies approved, and more personalized treatments are being developed thanks to genetic testing.

Conclusion

Using these advanced methods to find oncogenic mutations not only helps doctors diagnose cancer better but also affects how they treat it. As we learn more about genetic changes in cancer, modern pathology will play an even more important role in diagnosing and treating this disease.