@ijones98280, here's an excerpt from the American Cancer Society about the significance of finding out if a tumor is P16 positive or not

HPV (p16) testing https://www.cancer.org/cancer/types/oral-cavity-and-oropharyngeal-cancer/detection-diagnosis-staging/how-diagnosed.html
"For cancers of the throat, the biopsy samples are often tested (for the p16 protein) to see if HPV infection is present. This is a key part of staging (finding out if and how much the cancer has spread) and is considered when making treatment decisions for oropharyngeal cancer. This information can also help the doctor predict the probable course of the cancer, because people whose cancers are linked to HPV tend to do better than those whose cancers are not."

Here are a couple of related discussion where you can connect with other members with a similar diagnosis:
- Standard Procedure for Stage 1 OPSCC P16+?
https://connect.mayoclinic.org/discussion/standard-procedure-for-stage-1-opscc-p16/
- HPV P16 positive cancer
https://connect.mayoclinic.org/discussion/hpv-p16-positive-cancer/
See all https://connect.mayoclinic.org/group/head-neck-cancer/?search=p16&index=discussions

What is the next step for you?

A immunohistochemistry test is used to determine if the the cancer cells are HPV positive and specifically what sub type of HPV virus. Typically if the cell smears are positive on panel 16, this is what they are looking for. A small percentage show up on panel 18 so this is known as HPV positive P(panel)18+. The + means positive as well. We could say a patient will have HPV positive panel 16 positive, panel 18 negative type but then we could also say panels 1 through 32 are also negative with the exception of panel 16. It's simple to just say P16+. The "P" means panel. The + means positive. So it's not really a mystery but is somewhat a code that lets others know the specifics of the cancer for treatment. The treatments for p16 and p18 are different. This was all explained to me by an oncologist.