Radical radiotherapy for squamous cell carcinoma of the larynx--comparison of three-dimensional conformal radiotherapy with cobalt-60 teletherapy.

The aim of the study was to report the results of radical radiotherapy performed by three-dimensional conformal radiotherapy (3DCRT) for squamous cell carcinoma of the larynx and to compare these data with those obtained with two-dimensional radiotherapy (2DRT) realized with cobalt-60 teletherapy i.e. telecobalt therapy (TCT). Eighty patients with previously untreated laryngeal cancer were irradiated with curative intent at the University of Radiotherapy and Oncology Clinic (UCRO) in Skopje between February 1999 and December 2008. Radical radiotherapy with the TCT unit was performed on 38 patients between February 1999 and May 2005. From June 2005 to December 2008, 42 patients were treated with a linear accelerator using 3DCRT. Complete response rates three months after completion of radiotherapy were 84.2% (32 of 38) and 92.6% (39 of 42) in the group irradiated with TCT unit and in the group treated with 3DCRT, respectively. No statistically significant differences were observed either in locoregional control (LRC) or overall survival (OS) between the patients treated with two different radiotherapy techniques. The grade of acute reactions of the skin and the larynx differed significantly between the accomplished radiotherapy techniques (Nonparametric Mann-Whitney U Test; U=577.0; Z=-2.129; p=0.012, and U=497.0; Z=-2.90; p=0.001, respectively). There were statistically significant differences observed in the grade of late effects in the skin and in the subcutaneous tissue between the radiotherapy techniques used (Nonparametric Mann-Whitney U Test; U=425.0; Z=-3.593; p=0.001 and U=637.0; Z=-1.551; p=0.035, respectively). According to the confirmed advantage of 3DCRT in terms of reduced treatment toxicity observed in our study, we consider conformal techniques being a basis in definitive radiotherapy of squamous cell carcinoma of the larynx until the new revolutionary techniques will be clinically available.

Factors influencing the development of distant metastases in patients with head and neck squamous cell carcinoma.

PURPOSE: the aim of this retrospective study was to evaluate the frequency of distant metastases (DM) and to define factors that influence DM free survival (DMFS) in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: the charts of 201 patients with oral cavity, pharyngeal, or laryngeal carcinoma, treated with postoperative radiotherapy (RT) or definitive RT between 1999 and 2004 and achieved locoregional control were analyzed. RESULTS: DM occurred in 26 of 201 (12.9%) patients. The mean time of DM diagnosis was 16.5 months (range 5-35). The median time to death after diagnosis of DM was 5 months (range 1-13). The DMFS rate at 5 years was 84.8%. Univariate analysis demonstrated that the risk of DM was significantly influenced by age (p=0.047), cigarette smoking (p=0.024), ECOG performance status (PS) (p=0.008), location of the primary site (p=0.003), N stage (p<0.0001), overall stage (p<0.0001), histological differentiation (p<0.0001), levels of nodal involvement (p<0.0001), treatment modality (p<0.0002), presence of locoregional recurrence (LRR) (p<0.0001), and time to LRR (p<0.0001). In multivariate analysis nodal involvement (N1: p=0.007; N2: p=0.036; N3: p=0.043), and the time to LRR ≤ 6 months (p=0.037) were proven as independent factors that significantly influenced DMFS. CONCLUSION: development of DM in patients with HNSCC was significantly influenced by the presence of positive nodal status and the presence of LRR whose appearance was within 6 months of RT.

Prognostic factors in patients with recurrent head and neck cancer treated with reirradiation.

PURPOSE: The aim of this study was to determine the prognostic factors concerning overall survival (OS) and progression- free survival (PFS) following reirradiation in patients with recurrent squamous cell head and neck cancer (HNC). PATIENTS AND METHODS: We performed a retrospective analysis on 65 recurrent HNC patients treated with reirradiation for local/locoregional recurrence between 1999 and 2004 at the Institute of Radiotherapy and Oncology in Skopje. The initial treatment of their HNC consisted of radiotherapy following surgery, radiotherapy alone, or concurrent chemoradiotherapy. RESULTS: The median reirradiation dose was 39.8 Gy (range 24-58). Clinically complete response (CR) was observed in 9 (13.9%) patients. The median OS and PFS was 8 months (range 1-22) and 4.9 months (range 0-18), respectively. The univariate analysis of prognostic factors identified Karnofsky performance status (KPS), response to reirradiation, dose to recurrent site, and disease-free interval (DFI) as strongly associated with both OS and PFS. Initial tumor site and cumulative dose had a significant influence only on OS. Multivariate analysis revealed that response to reirradiation and the radiation dose to the recurrent site were two independent variables significantly influencing OS (p<0.0001 and p=0.049, respectively). The only significant independent prognostic factor for PFS was response to reirradiation (p=0.0008). CONCLUSION: The necessity of improvement of patients' outcome allows us to consider concurrent chemoradiotherapy as a more efficient treatment strategy that has a potential to increase the response to reirradiation of unresectable recurrent HNC. Using higher radiation doses is also expected to enhance the response rates and consequently to positively influence OS and PFS.