Non-Hodgkin's lymphomas (NHL) are an important variety of gastrointestinal tumors with increasing incidence and prevalence. Traditional management of NHL with chemotherapy is challenging and expanding evidence points to significant tumor response to radiation therapy (RT). However, there exists a wide range of radiation-related toxicities. Optimization of exact tumor marking coupled with minimization of the radius of radiation delivery is essential to increase patient's tolerance and decrease side effects of the treatment. We report our experience with mantle cell lymphoma of the colon treated with precision RT after endoscopic placement of resolution clips in a "shooting target" fashion in a patient who failed conventional chemotherapy. Fourteen months after completion of RT, the patient remains in complete remission.