Clinical trials

This project aims to compare the oncological and functional outcomes of patients with mid-rectal cancer who have a low risk of local recurrence (without MRF involvement) and who either receive or do not receive neoadjuvant chemoradiotherapy (nCRT). Main Question: H0: In mid-rectal cancer patients without MRF involvement (cT2N+ and cT3Nx), there is no difference in 3-year disease-free survival between direct TME and TME after nCRT. H1: In mid-rectal cancer patients without MRF involvement (cT2N+ and cT3Nx), direct TME is associated with worse 3-year disease-free survival compared to TME after nCRT. Participants already taking both interventions as part of their regular medical care for rectal cancer will be recruited in a prospective database for 5 years.

This prospective observational cohort study aims to compare the clinical and procedural outcomes of Endoscopic Submucosal Dissection (ESD) and Transanal Minimally Invasive Surgery (TAMIS) for the treatment of early-stage rectal neoplasia. The study will evaluate recurrence rates, en bloc resection rates, R0 resection rates, procedure time, complication rates, and length of hospital stay over a 1-year follow-up period. Data will be collected from patients treated at multiple centers with expertise in ESD and TAMIS.

The goal of this observational study is to learn how a common surgery called lateral internal sphincterotomy (LIS) affects people with chronic anal fissures, a painful tear near the anus. The study will look at whether this surgery helps lower problems like pain and incontinence, and how it affects quality of life and mental health. The main questions the study aims to answer are: Does LIS surgery lower the rate of incontinence one year after surgery? Does it improve quality of life, reduce pain, and increase patient satisfaction? Participants will: Have surgery for chronic anal fissure called LIS. Complete short surveys about pain and mental health at 1 week, 3 months, and 12 months. Answer questions about bowel function, incontinence and daily life at 3 and 12 months. Researchers will follow about 300 adults at hospitals across the Turkey. This study will help improve future treatment decisions and make surgery safer and more effective.

The goal of this prospective observational study is to learn more about how a specific type of DNA repair issue-called mismatch repair deficiency (dMMR)-affects colon cancer in people living in Turkey. The study will look at how often dMMR occurs, how it is reported, and how it relates to treatment outcomes. The main questions it aims to answer are: * How common is dMMR in colon cancer, and does it vary by where the tumor is in the colon? * How often is MSI (microsatellite instability) status reported in colon cancer biopsy reports before surgery? * How do different types of dMMR (such as MLH1/PMS2 loss, MSH2/MSH6 loss, or sporadic cases) affect survival over three years? Participants will: * Be people who had surgery for colon cancer between June 1, 2025 and May 31, 2026 at hospitals in Turkey that treat more than 30 colon cancer cases each year. * Have their medical and pathology data reviewed, including information about tumor location, biopsy results, surgery, and treatment. This study will not involve any new treatments. Instead, it will use existing medical records to better understand how to improve care and identify people who may benefit from immunotherapy. Results from this study will be shared at scientific meetings and published in medical journals.