Which of the following malignant tumours is radioresistant?
**Core Concept:** Malignant tumours are generally less radioresistant compared to benign tumours. Radioresistance refers to a cancer cell's ability to survive exposure to ionizing radiation and continue dividing despite the damage.
**Why the Correct Answer is Right:** Lymphomas, especially those originating from B-cells, are relatively radioresistant due to their high rate of DNA repair and efficient cell cycle control. In this case, the correct answer is "D." Hodgkin lymphoma (HL) is a type of lymphoma that exhibits radioresistance, which allows it to survive radiation therapy and potentially cause relapse.
**Why Each Wrong Option is Incorrect:** Option A (Lung cancer) is generally considered radioresistant, but this is more related to its growth rate rather than inherent radioresistance. Option B (Breast cancer) is also radioresistant due to its high rate of DNA repair, but it is not as radioresistant as Hodgkin lymphoma. Option C (Leukemia) exhibits varying degrees of radioresistance, but it is not as radioresistant as Hodgkin lymphoma.
**Clinical Pearl:** In clinical practice, radiation therapy is often used in combination with chemotherapy for lymphoma treatment, as chemotherapy can overcome the radioresistance. This targeted approach improves outcomes for patients with lymphoma.
**Correct Answer:** .
D. Hodgkin lymphoma (HL) is a type of lymphoma characterized by Reed-Sternberg cells and is radioresistant due to its high rate of DNA repair and efficient cell cycle control.