Circulating tumour cells in locally advanced head and neck cancer: preliminary report about their possible role in predicting response to non-surgical treatment and survival.

BACKGROUND AND PURPOSE: The mechanism of dissemination of locally advanced head and neck cancer (LAHNC) is far to be resolved. Circulating tumour cells (CTC) have been identified as a prognostic factor in metastatic breast and prostate cancer. This prospective multi-centric analysis studied the possible role of CTC identification in LAHNC. MATERIALS AND METHODS: CTC were searched in 73 patients with LAHNC (oropharynx, n=39; nasopharynx, n=10; larynx, n=10; paranasal sinuses, n=6, of whom 3 with sinonasal undifferentiated carcinoma, SNUC; hypopharynx, n=5; oral cavity, n=3). All of them (apart from SNUC) had squamous cell cancers. The relationship between CTC positivity and other clinical prognostic factors has been investigated. Response to treatment and survival has been related with changes in CTC number during the treatment. RESULTS: CTC were frequently identified in oro- and hypopharyngeal cancer and in SNUC. They were more frequent in stage IV than in stages I-III disease (18% versus 6%, p=NS (not significant)). Partial or complete response (CR) was related with the absence or disappearance of CTC during treatment (p=0.017). A decrease in the CTC number or their absence throughout the treatment seems also related with non-progressive disease, after both complete or incomplete remission and with the proportion of patients alive and NED (no evidence of disease) (p=0.009). CONCLUSIONS: These preliminary data suggest a possible role of CTC determination in head and neck cancer. Additional and longer follow up data need to be collected to confirm these findings.

Association between single nucleotide polymorphisms in the XRCC1 and RAD51 genes and clinical radiosensitivity in head and neck cancer.

PURPOSE: Individual variability in radiosensitivity is large in cancer patients. Single nucleotide polymorphisms (SNPs) in genes involved in DNA repair and in protection against reactive oxygen species (ROS) could be responsible for such cases of radiosensitivity. We investigated the association between the occurrence of acute reactions in 101 patients with squamous cell carcinoma of the head and neck (SCCHN) after radiotherapy (RT) and five genetic polymorphisms: XRCC1 c.1196A>G, XRCC3 c.722C>T, RAD51 (c.-3429G>C, c.-3392G>T), and GSTP1 c.313A>G. MATERIALS AND METHODS: Genetic polymorphisms were detected by high resolution melting analysis (HRMA). The development of acute reactions (oral mucositis, skin erythema and dysphagia) associated with genetic polymorphisms was modeled using Cox proportional hazards, accounting for biologically effective dose (BED). RESULTS: Development of grade ≥2 mucositis was increased in all patients (chemo-radiotherapy and radiotherapy alone) with XRCC1-399Gln allele (HR=1.72). The likelihood of developing grade ≥2 dysphagia was higher in carriers of RAD51 c.-3429 CC/GC genotypes (HR=4.00). The presence of at least one SNP or the co-presence of both SNPs in XRCC1 p.Gln399Arg /RAD51 c.-3429 G>C status were associated to higher likelihood of occurrence of acute toxicities (HR=2.03). CONCLUSIONS: Our findings showed an association between genetic polymorphisms, XRCC1 c.1196A>G and RAD51 c.-3429 G>C, and the development of radiation-induced toxicities in SCCHN patients.

On-line image guidance for frameless stereotactic radiotherapy of lung malignancies by cone beam CT: comparison between target localization and alignment on bony anatomy.

INTRODUCTION: Free-breathing stereotactic radiotherapy for lung malignancies requires reliable prediction of respiratory motion and accurate target localization. A protocol was adopted for reproducibility and reduction of respiratory motion and for target localization by CBCT image guidance. Tumor respiratory displacements and tumor positioning errors relative to bony anatomy alignment are analyzed. MATERIALS AND METHOD: Image guided SRT was performed for 99 lung malignancies. Two groups of patients were considered: group A did not perform any breathing control; group B controlled visually their respiratory cycle and volumes on an Active Breathing Coordinator (ABC) monitor during the acquisition of simulation CT and CBCT, and treatment delivery. GTV on end inhale and exhale CT data sets were fused in an ITV and the extent of tumor motion evaluated between these 2 phases. A pre-treatment CBCT was acquired and aligned to the reference CT using bony anatomy; for tumor positioning the ITV contour on the reference CT was matched to the visible tumor on CBCT. Interobserver variability of tumor positioning was evaluated. ITV and CBCT tumor dimensions were compared. RESULTS: 3D tumor breathing displacement (mean+/-SD) was significantly higher for group A (14.7+/-9.9 mm) than for group B (4.7+/-3.1 mm). The detected differences between tumor and bony structure alignment below 3 mm were 68% for group B and 45% for group A, reaching statistical significance. Interobserver variability was 1.7+/-1.1 mm (mean+/-SD). Dimensions of tumor image on CBCT were consistent with ITV dimensions for group B (max difference 14%). CONCLUSIONS: The adopted protocol seems effective in reducing respiratory internal movements and margin. Tumor positioning errors relative to bony anatomy are also reduced. However bony anatomy as a surrogate of the target may still lead to some relevant positioning errors. Target visualization on CBCT is essential for an accurate localization in lung SRT.

Cone beam CT image guidance for intracranial stereotactic treatments: comparison with a frame guided set-up.

PURPOSE: An analysis is performed of the setup errors measured by a kV cone beam computed tomography (CBCT) for intracranial stereotactic radiotherapy (SRT) patients immobilized by a thermoplastic mask and a bite-block and positioned using stereotactic coordinates. We evaluated the overall positioning precision and accuracy of the immobilizing and localizing systems. The potential of image-guided radiotherapy to replace stereotactic methods is discussed. METHODS AND MATERIALS: Fifty-seven patients received brain SRT. After a frame-guided setup, before each fraction (131 fractions), a CBCT was acquired and the detected displacements corrected online. Translational and rotational errors were analyzed calculating overall mean and standard deviation. A separate analysis was performed for bite-block (in conjunction with mask) and for simple thermoplastic mask. Interobserver variability for CBCT three-dimensional registration was assessed. The residual error after correction and intrafractional motion were calculated. RESULTS: The mean module of the three-dimensional displacement vector was 3.0 +/- 1.4 mm. Setup errors for bite block and mask were smaller (2.9 +/- 1.3 mm) than those for thermoplastic mask alone (3.2 +/- 1.5 mm), but statistical significance was not reached (p = 0.15). Interobserver variability was negligible. The maximum margin calculated for residual errors and intra fraction motion was small but not negligible (1.57 mm). CONCLUSIONS: Considering the detected setup errors, daily image guidance is essential for the efficacy of SRT treatments when mask immobilization is used, and even when a bite-block is used in conjunction. The frame setup is still used as a starting point for the opportunity of rotational corrections. Residual margins after on-line corrections must be evaluated.

Relevance of biologically equivalent dose values in outcome evaluation of stereotactic radiotherapy for lung nodules.

PURPOSE: Different biologically equivalent dose (BED) values associated with stereotactic radiotherapy (SRT) of patients with primary and metastatic pulmonary nodules were studied. The BED values were calculated for tumoral tissue and low alpha/beta ratio, assuming that better local response could be obtained by using stereotactic high-BED treatment. METHODS AND MATERIALS: Fifty-eight patients with T1-T3 N0 non-small-cell lung cancer and 46 patients with metastatic lung nodules were treated with SRT. The BED was calculated for alpha/beta ratios of 3 and 10. Overall survival (OS) was assessed according to Kaplan-Meier and appraised as a function of three BED levels: low (30-50 Gy), medium (50-70 Gy), and high (70-98 Gy; alpha/beta = 10). RESULTS: The OS rates for all 104 patients at 12, 24, and 36 months were 73%, 48.3%, and 35.8%, respectively. Local response greater than 50% for low, medium, and high BED values was observed in 54%, 47%, and 73%, respectively. In the high-BED treated group, OS rates at 12, 24, and 36 months (80.9%, 70%, and 53.6%, respectively) were significantly improved compared with low- (69%, 46.1%, and 30.7%, respectively) and medium-BED (67%, 28%, and 21%, respectively) treated patients. Results are also discussed in terms of BED calculated on alpha/beta 3 Gy characteristic of the microcapillary bed. No acute toxicity higher than Grade 1 was observed. CONCLUSIONS: Radioablation of pulmonary neoplastic nodules may be achieved with SRT delivered by using a high-dose fraction with high BED value.

Late treatment-related complications in 214 patients with extremity soft-tissue sarcoma treated by surgery and postoperative radiation therapy.

BACKGROUND: We assessed the occurrence of long-bone fracture and other side effects in a group of 214 consecutive patients who underwent radical excision for soft-tissue sarcoma of the limb followed by postoperative irradiation. METHODS: Two hundred fourteen patients underwent postoperative irradiation after radical excision of soft-tissue sarcoma of the limb; 156 (73%) received postoperative brachytherapy (BRT) plus external-beam radiation therapy (EBRT), and 58 (27%) underwent postoperative EBRT only. All patients were followed-up for a median time of 4.5 years (range 3 months to 10 years). RESULTS: Seven patients developed bone fracture, which is considered severe morbidity; time between surgery and occurrence of fracture ranged between 10 and 72 months (average 31). Severe sclerosis with impairment of limb function was diagnosed in 5 and peripheral nerve damage in 3 patients. Wound complications were detected in 8 patients. CONCLUSIONS: In our series, no statistically significant correlation between bone fracture and clinical features or "technical" parameters was found, but all of the patients who experienced bone fracture (7 of 7) were postmenopausal women >55 years old.

Radical radiotherapy for early glottic cancer: Results in a series of 1087 patients from two Italian radiation oncology centers. II. The case of T2N0 disease.

PURPOSE: To retrospectively evaluate local control rates, late damage incidence, functional results, and second-tumor occurrence according to the different patient, tumor, and treatment features in a large bi-institutional series of T2 glottic cancer. METHODS AND MATERIALS: A total of 256 T2 glottic cancer cases treated consecutively with radical intent at the Florence University Radiation Oncology Department (FLO) and at the Radiation Oncology Department of the University of Brescia, Istituto del Radio "O. Alberti" (BS) were studied. Cumulative probability of local control (LC), disease-specific survival (DSS), and overall survival (OS) rates were calculated and compared in the different clinical and therapeutic subgroups by both univariate and multivariate analysis. Types of relapse and their surgical salvage were evaluated, along with the functional results of treatment. Late-damage incidence and second-tumor cumulative probability (STP) were also calculated. RESULTS: In the entire series, 3-year, 5-year, and 10-year OS rates were, respectively, 73%, 59%, and 37%. Corresponding values for cumulative LC probability were 73%, 73%, and 70% and for DSS, 89%, 86%, and 85%, taking into account surgical salvage of relapsed cases. Seventy-three percent of the patients were cured with function preserved. Main determinants of a worse LC at univariate analysis were larger tumor extent and impaired cord mobility. At multivariate analysis, the same factors retained statistical significance. Twenty-year STP was 23%, with second-tumor deaths less frequent than larynx cancer deaths (20 of 256 vs. 30 of 256). Incidence of late damage was higher in the first decade of accrual (22%) than in the last decade (10%, p = 0.03); the same was true for severe late damage (9% vs. 1.8%). CONCLUSION: Present-day radical radiotherapy can be considered a standard treatment for T2 glottic cancer. Better results are obtained in patients with less extended disease. Late damage is relatively infrequent, but a careful follow-up is warranted for early detection not only of relapses (because salvage surgery is feasible) but also of second malignant tumors, which constitute a relevant but not the leading cause of death in these patients and are potentially curable.

Radical radiotherapy for early glottic cancer: Results in a series of 1087 patients from two Italian radiation oncology centers. I. The case of T1N0 disease.

PURPOSE: To retrospectively evaluate local control rates, late damage incidence, functional results, and second tumor occurrence according to the different patient, tumor, and treatment features in a large bi-institutional series of T1 glottic cancer. METHODS AND MATERIALS: A total of 831 T1 glottic cancer cases treated consecutively with radical intent at the Florence University Radiation Oncology Department (FLO) and at the Radiation Oncology Department of the University of Brescia-Istituto del Radio "O. Alberti" (BS) were studied. Actuarial cumulative local control probability (LC), disease-specific (DSS), and overall survival (OS) rates have been calculated and compared in the different clinical and therapeutic subgroups with both univariate and multivariate analysis. Types of relapse and their surgical salvage have been evaluated, along with the functional results of treatment. Late damage incidence and second tumor cumulative probability (STP) have been also calculated. RESULTS: In the entire series, 3-, 5-, and 10-year OS was equal to 86%, 77%, and 57%, respectively. Corresponding values for LC were 86%, 84%, and 83% and for DSS 96%, 95%, and 93%, taking into account surgical salvage of relapsed cases. Eighty-seven percent of the patients were cured with function preserved. Main determinants of a worse LC at univariate analysis were: male gender, earlier treatment period, larger tumor extent, anterior commissure involvement, and the use of Cobalt 60. At multivariate analysis, only gender, tumor extent, anterior commissure involvement, and beam type retained statistical significance. Higher total doses and larger field sizes are significantly related (logistic regression) with a higher late damage incidence. Scatterplot analysis of various combinations of field dimensions and total dose showed that field dimensions >35 and <49 cm2, together with doses of >65 Gy, offer the best local control results together with an acceptably low late damage incidence. Twenty-year STP was equal to 23%, with second tumor deaths being more frequent than larynx cancer deaths (67 of 831 vs. 46/831). CONCLUSION: The results of this study support the opinion, suggested by some international guidelines, that radiotherapy is standard treatment for T1 glottic cancer. Better results are obtained in patients with less extended disease and with 4-6 MV photon beams. The use of doses in excess of 65 Gy and of field sizes of 36-49 cm2 is probably the best technical choice available. Late damage is infrequent, but careful follow-up is warranted to detect early not only relapses (because conservative salvage surgery is feasible), but also second malignant tumors, which constitute the main cause of death in these patients and are potentially curable.