Pembrolizumab is a type of medication known as an immunotherapy. It works by helping your immune system fight cancer. Pembrolizumab targets a specific protein on the surface of cancer cells called PD-1. By blocking this protein, pembrolizumab helps your immune system recognize and attack cancer cells more effectively. This medication is used in the trial to see how well it works in treating different types of advanced solid tumors, which are cancers that have spread or cannot be removed by surgery. The trial is also looking at how certain biomarkers, which are characteristics of the cancer, might predict how well pembrolizumab works for different patients.

Anal Squamous Cell Carcinoma – This is a type of cancer that forms in the tissues of the anus. It typically begins in the squamous cells, which are flat cells lining the anus. The disease may start as a small growth or sore that does not heal. Over time, it can invade deeper layers of tissue and spread to nearby lymph nodes. As it progresses, it may cause symptoms such as bleeding, pain, or changes in bowel habits. The progression can vary, with some cases remaining localized while others spread to distant organs.

Biliary Adenocarcinoma – This cancer originates in the bile ducts or gallbladder. It begins in the glandular cells that line these structures. The disease often progresses slowly, initially causing few symptoms. As it advances, it can block bile ducts, leading to jaundice, abdominal pain, and weight loss. The cancer may spread to nearby organs and lymph nodes. Over time, it can become more aggressive and difficult to manage.

Neuroendocrine Tumors – These tumors develop from neuroendocrine cells, which have traits of both nerve and hormone-producing cells. They can occur in various organs, including the lungs, pancreas, and gastrointestinal tract. The progression is often slow, and symptoms may not appear until the tumor is large or has spread. Symptoms depend on the tumor’s location and may include pain, hormonal imbalances, or digestive issues. Some tumors may produce hormones, leading to specific syndromes. The disease can remain stable for years or become aggressive and spread to other parts of the body.

Endometrial Carcinoma – This cancer forms in the lining of the uterus, known as the endometrium. It typically begins as a localized growth and can cause symptoms like abnormal vaginal bleeding. As it progresses, it may invade the muscular wall of the uterus and spread to nearby tissues. The disease can extend to the cervix, ovaries, and lymph nodes. In advanced stages, it may metastasize to distant organs. The progression rate can vary, with some cases remaining confined to the uterus for a long time.

Cervical Squamous Cell Carcinoma – This cancer arises from the squamous cells on the surface of the cervix. It often begins as a precancerous condition called dysplasia, which can progress to invasive cancer. The disease may cause symptoms such as abnormal vaginal bleeding or discharge. As it advances, it can invade deeper cervical tissues and spread to nearby structures. The cancer may extend to the pelvic lymph nodes and beyond. The progression can be slow, allowing for early detection and intervention.

Vulvar Squamous Cell Carcinoma – This cancer develops in the squamous cells of the vulva, the external part of the female genitalia. It often starts as a precancerous lesion that can progress to invasive cancer. Symptoms may include itching, pain, or a visible lump. As the disease advances, it can invade deeper tissues and spread to nearby lymph nodes. The cancer may extend to the urethra, vagina, or anus. The progression can vary, with some cases remaining localized for extended periods.

Small Cell Lung Carcinoma – This is a fast-growing type of lung cancer that originates in the bronchi, the main airways of the lungs. It is characterized by small, round cancer cells that multiply quickly. The disease often spreads rapidly to other parts of the body, including the lymph nodes, liver, and brain. Symptoms may include coughing, chest pain, and shortness of breath. Due to its aggressive nature, it is often diagnosed at an advanced stage. The progression is typically rapid, requiring prompt medical attention.

Mesothelioma – This cancer affects the mesothelium, a thin layer of tissue covering most internal organs. It is most commonly found in the lining of the lungs and chest wall. The disease progresses slowly, often taking years to develop after exposure to risk factors like asbestos. Symptoms may include chest pain, shortness of breath, and fluid buildup around the lungs. As it advances, it can invade nearby tissues and spread to distant organs. The progression can vary, with some cases remaining localized for a long time.

Thyroid Carcinoma – This cancer originates in the thyroid gland, located at the base of the neck. It often begins as a small nodule that may not cause symptoms initially. As it progresses, it can lead to a lump in the neck, changes in voice, or difficulty swallowing. The disease may spread to nearby lymph nodes and, in some cases, to distant organs. The progression rate can vary, with some types growing slowly and others more rapidly. Early detection is possible due to its location and symptoms.

Salivary Gland Carcinoma – This cancer forms in the salivary glands, which produce saliva in the mouth. It can occur in any of the major or minor salivary glands. The disease may start as a painless lump or swelling in the mouth or neck. As it progresses, it can cause pain, numbness, or difficulty swallowing. The cancer may invade nearby tissues and spread to lymph nodes. The progression can vary, with some tumors growing slowly and others more aggressively.

Advanced Solid Tumors with Microsatellite Instability-High – These are solid tumors characterized by a high level of microsatellite instability, a condition of genetic hypermutability. They can occur in various organs and are often associated with a defect in the DNA mismatch repair system. The disease may progress slowly or rapidly, depending on the tumor type and location. Symptoms vary widely based on the affected organ and may include pain, weight loss, or organ dysfunction. The tumors can spread to nearby tissues and distant organs. The progression is influenced by the tumor’s genetic characteristics and environment.

Advanced Solid Tumors with Mismatch Repair Deficiency – These tumors have a deficiency in the mismatch repair system, leading to genetic instability. They can develop in various organs and are often associated with hereditary cancer syndromes. The disease may progress at different rates, depending on the tumor type and location. Symptoms are diverse and depend on the affected organ, potentially including pain, bleeding, or obstruction. The tumors can invade nearby tissues and metastasize to distant sites. The progression is influenced by genetic factors and the tumor’s biological behavior.

Advanced Solid Tumors with Tumor Mutational Burden-High – These are solid tumors with a high number of mutations per megabase of DNA. They can occur in various organs and are often associated with a high level of genetic diversity. The disease may progress slowly or rapidly, depending on the tumor type and location. Symptoms vary widely based on the affected organ and may include pain, weight loss, or organ dysfunction. The tumors can spread to nearby tissues and distant organs. The progression is influenced by the tumor’s genetic characteristics and environment.