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A MyLungCancerTeam Member asked a question 💭
Manteca, CA

Immunohistochemistry (block
A2)
P40 positive
TTF-1 pos negative, pos
itive internal control

December 31, 2025
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MyLungCancerTeam

What does P40 positive and TTF-1 negative mean?

When immunohistochemistry (IHC) shows P40 positive and TTF-1 negative, it suggests your lung cancer is likely squamous cell carcinoma, a type of non-small cell lung cancer.

Here's what these markers tell us:

- P40 positive: P40 is a protein marker that lights up in squamous Show Full Answer

What does P40 positive and TTF-1 negative mean?

When immunohistochemistry (IHC) shows P40 positive and TTF-1 negative, it suggests your lung cancer is likely squamous cell carcinoma, a type of non-small cell lung cancer.

Here's what these markers tell us:

- P40 positive: P40 is a protein marker that lights up in squamous cell lung cancers. When it's positive, it strongly suggests this type of cancer.

- TTF-1 negative: TTF-1 (thyroid transcription factor-1) is typically positive in adenocarcinoma, another type of non-small cell lung cancer. When it's negative, it helps rule out adenocarcinoma.

- Positive internal control: This confirms the test worked properly and the results are reliable.

IHC uses special antibodies attached to dyes that bind to specific proteins in tissue samples. When viewed under a microscope, these dyes help identify what type of cancer cells are present.

Understanding your specific lung cancer type helps your doctor create the most effective treatment plan for you. Your healthcare team can explain how these results affect your treatment options.

December 31, 2025

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A MyLungCancerTeam Member asked a question 💭
Manteca, CA

A MyLungCancerTeam Member asked a question 💭
Manteca, CA