Squamous Cell Carcinoma of Skin

The goal of this clinical trial is to learn if N17350 works to treat advanced solid tumors in adults. It will also learn about the safety of N17350 and help determine the best dose to use in future studies. The main questions it aims to answer are: 1. Does N17350 cause tumors to shrink or stop growing in some participants with advanced solid tumors? 2. Are there any side effects for participants when taking N17350? 3. What is the safest dose of N17350 and the dose that should be used for further study? 4. Researchers will give N17350 directly into tumor lesions using a needle (intratumoral injection). This is an open-label study, meaning all participants will receive N17350 and there is no placebo. Participants will: 1. Receive injections of N17350 into tumor lesions every second week for 8 or 12 weeks 2. Visit the clinic regularly for checkups, blood tests, and monitoring for side effects 3. Have imaging scans (such as CT or MRI) to measure tumors and assess response 4. Provide blood samples and, when required, tumor samples to help researchers understand how N17350 affects the tumor and the immune system

The goal of this clinical trial is to learn if N17350 works to treat advanced solid tumors in adults. It will also learn about the safety of N17350 and help determine the best dose to use in future studies. The main questions it aims to answer are: 1. Does N17350 cause tumors to shrink or stop growing in some participants with advanced solid tumors? 2. Are there any side effects for participants when taking N17350? 3. What is the safest dose of N17350 and the dose that should be used for further study? 4. Researchers will give N17350 directly into tumor lesions using a needle (intratumoral injection). This is an open-label study, meaning all participants will receive N17350 and there is no placebo. Participants will: 1. Receive injections of N17350 into tumor lesions every second week for 8 or 12 weeks 2. Visit the clinic regularly for checkups, blood tests, and monitoring for side effects 3. Have imaging scans (such as CT or MRI) to measure tumors and assess response 4. Provide blood samples and, when required, tumor samples to help researchers understand how N17350 affects the tumor and the immune system

This is a single-center, non-interventional, observational study that evaluates the correlation of circulating tumor DNA (ctDNA) testing to cancer relapse for participants with squamous cell carcinomas (HNC) of the head and neck mucosa and skin after curative-intent primary radiation or surgery.