Breast Cancer and Perineural Invasion

cashemire,

That's interesting what you said about pain because I had terrible pain in my breast and I recall how uncomfortable the seat belt was on my breast. Some people think that breast cancer is not painful but they are so wrong.
Isn't it frustrating to not know the ramifications of the nerve involvement? It's been around 2 1/2 years since my surgery and radiation and I still have deep nerve like pain in my breast that comes and goes.
Now I have developed transient lymphedema in my breast. I didn't even know that you could have breast lymphedema.
Thank you for telling me about your experience. I appreciate it.
Katrina

Good morning everyone. I was told a week ago that Perineural Invasion is present after doing a double mastectomy. However , my margins are negative for carcinoma. My oncologist are suggesting chemotherapy. After surgery the pathology report read that the cancer was not in my right breast and no spread to my lymph nodes from my left breast which had the small tumor. I do not want to do chemo. Any suggestions.

Had perineural invasion indentified on pathology for invasive lobular carcinoma. Had lumpectomy & met with Dr's today to discuss treatment plan. I asked about PNI & Dr told me not to worry because cancer doesn't travel down the nerve with breast cancer. I really didn't like that answer..Everything I see online states its rare in breast cancer & there isn't much info, but its not good in prostate cancer..Anyone have anymore info????

I used ScienceDirect.com to look this up. I’ve found this site often has info that is very new, sometimes not yet published. It seems most of the info about pni is associated with TLSs - that’s evidently something they’re doing more research on now, and have finally included breast cancer. I found it all a bit unclear. But it seems perineural invasion is found in many breast cancers but in non-significant amounts. It may or may not be an indicator of problems (this is my unprofessional understanding of what I read) but it is an indicator of aggression in TNBC.
I put the links I found below, plus one about TLS from Nature.com that explains what it is.

Tertiary Lymphoid Structures (TLSs) and Stromal Blood Vessels Have Significant and Heterogeneous Impact on Recurrence, Lymphovascular and Perineural Invasion amongst Breast Cancer Molecular Subtypes
https://pmc.ncbi.nlm.nih.gov/articles/PMC10136904/
5P Tertiary lymphoid structures (TLS) presence and stromal blood vessels heterogeneity differentially influence recurrence, lymphovascular, and perineural invasion in breast cancer molecular subtypes
https://www.sciencedirect.com/science/article/pii/S0923753423023451
Perineural invasion-associated biomarkers for tumor development
(No breast cancer mentioned, but just about every other kind!)
https://www.sciencedirect.com/science/article/pii/S0753332222010800
Tertiary lymphoid structures in the era of cancer immunotherapy
https://www.nature.com/articles/s41568-019-0144-6

@kluckett75, you may also be interested in the discussion that @katrina123 started on this topic:
- Breast Cancer and Perineural Invasion https://connect.mayoclinic.org/discussion/breast-cancer-and-perineural-invasion/

I had perineural invasion identified two weeks ago on surgical pathology for invasive ductal carcinoma that otherwise has a very positive prognosis. (small, pT1cN0?, tubular, ER+, PR+, HER2-, Ki-67 5%)
I meet with Mayo Clinic doctors tomorrow to discuss treatment plan, and will ask about this. I'll edit this posting when I have more information.

Mayo Clinic says my tumor was classified as pT1cNx. With its small size and characteristics, the oncologist tells me the existence of perineural invasion in my case is insignificant and can be ignored. So I start on an aromatase inhibitor next week to suppress estrogen and reduce the risk of recurrence.
Note: your cancer is unique to you, and my experience cannot be compared to yours.

I had a left breast mastectomy 11/19/25 and margins were clear. Perineural invasion was identified. My breast cancer was adenoid cystic carcinoma. I’m going to discuss with my oncologist as it wasn’t mentioned at my post op
With surgeon or last week with oncologist. I just saw it on the pathology report and wonder what it means. I don’t know if it means that cancer spread along the nerve or if it was just in the immediate nerves around the tumor. My TNM was T2N0 no metastasis as lymph nodes were negative for cancer. Tumor was 4x2x2 cm. Having a follow up with oncologist but may seek a second opinion regarding this finding.

@georgia2025, that must've been scary to find on your pathology report. Have you had a chance to speak with your surgeon or oncologist for further clarification? What did you find out?

@georgia2025
Hello, I also have adenoid cystic carcinoma. Pending cardiac clearance I'm scheduled for lumpectomy on 02/27/26. I'll be glad to get the cancer out! I am concerned about perineural invasion because I do get what seems to be nerve pain in my left breast. So, I have to wait for the after surgery pathology report. My surgeon said that I don't need chemo or radiation which at first made me happy but now I'm a bit worried. Too much reading on the internet is not good! LOL! I'm trying to trust the professionals. My case has been presented to two different tumor boards so I know a lot of experts have been involved in my plan of care. Anyway, I hope you are doing well on your journey.