Radiosensitization of advanced squamous cell carcinoma of the head and neck with cisplatin during concomitant radiation therapy

Treatment regimens for advanced squamous cell carcinoma of the head and neck require both attention to local tumor burden as well as contingencies for control of disseminated disease. Relatively new protocols utilizing cisplatin for radiosensitization of tumor cells during concomitant radiotherapy have shown progress in providing effective tumor control. Cisplatin as a chemotherapeutic agent induces DNA changes in malignant cells that may be mutagenic or lethal. Additionally, when used concurrently with radiation therapy, cisplatin acts as a radiosensitizer, increasing damage to malignant nuclear DNA to enhance the anti-neoplastic capability of radiotherapy. The mechanisms by which this radiosensitization occurs remain controversial, although one leading theory involves cisplatin's ability to inhibit sublethal damage repair in radiated tumor cells. Recent investigations utilizing cisplatin with concurrent radiation for treatment of advanced squamous cell carcinomas of the head and neck are reviewed. The variations in protocols presented include route of administration, dosing, scheduling, timing with surgery, and combination therapy with 5-fluorouracil and radiation. Higher response rates, prolonged mean survival, increased survival rates, longer local recurrence-free survival rates, and considerable organ preservation with the use of concurrent cisplatin and radiation have been demonstrated by these studies. Further investigation of concurrent cisplatin and radiotherapy in patients with advanced disease is justified.