[SIB-IMRT radiotherapy given concomitantly with cisplatin for locally advanced squamous cell head and neck cancer (SCHNC). Evaluation of the early results and toxicity].

UNLABELLED: Concomitant radiochemotherapy become the treatment of choice for locally advanced SCHNC. This strategy of treatment has a limitation, which is an acute and late toxicity. The IMRT technique provides the possibility of better sparing of healthy tissue. Radiobiological and clinical data also suggest that accelerated fractionation and higher dose per fraction given in GTV may produce better locoregional control. Therefore it might be expected that concomitant chemotherapy and SIB-IMRT radiotherapy could increase locoregional control and reduce acute and late radiation reactions. The evaluation of early results and toxicity of this treatment modality is presented.

AIM OF STUDY: The evaluation of the early results and toxicity of SIB-IMRT radiotherapy given concomitantly with cisplatin for locally advanced squamous cell head and neck cancer (SCHNC).

METHODS: SIB-IMRT technique was applied. The boost volume was limited to the GTV + 3mm margin (macroscopic tumor extension was defined on the basis of CT and/or MRI examinations). Dose per fraction given to this volume was 2.25 Gy up to 67.5 Gy of total dose. The PTV-CTV + 3mm - was defined as an area of increased risk of microscopic spread. Dose per fraction given to this volume was 2 Gy up to 60 Gy. The PTV1-ETV+ 3mm (electively irradiated volume) received dose per fraction -1.8 Gy up to 54-56 Gy. Overall treatment time was 6 weeks (5 fractions per week, 30 fractions). Concomitant chemotherapy consisted of cisplatin in daily dose100mg/m2 given two times during irradiation (1 and 22 day of treatment). The evaluation of early tolerance was performed once weekly during the treatment than during the follow up every 2 months. The early reactions were scored according to the EORTC/RTOG scale.

MATERIAL: Between June 2006 and December 2009 99 patients diagnosed with III and IV clinical stage of SCHNC were treated with this method. 65 patients were diagnosed with oropharyngeal cancer, 18 with laryngeal cancer and 16 with hypopharyngeal cancer. PEG was performed at 65 patients before treatment for better alimentation during radiochemotherapy.

RESULTS: No severe life risking complications were observed a no concequentional late effects were observed. Extended mucositis grade III according RTOG/EORTC scale were observed only in boost region in 80% patients just after treatment was completed. In 2 patients ulceration were observed in tumour side which have healed up spontaneously within two months after treatment. 55% patients were suffering for III xerostomia and 41% for middle after the treatment. Majority of side effects were cured within 4 months after irradiation. The PEG was removing in 92% patients 2 months after treatment. The median follow-up time is 28 months (ranged from 14 m to 58 m). Actuarial 2-years overall survival and disease-free survival is respectively 90% and 82%, probability of locoregional recurrence at 2-years is 14% and 5-years estimated is 17,5%.

CONCLUSIONS: At the present moment it might be concluded that accelerated radiotherapy with SIB-IMRT given concomitantly with cisplatin produce excellent local control in patients treated of III-IV stage SCHNC without increasing toxicity.