RESUMEN
PURPOSE: Dosimetric evaluations of single and multiple liver tumours performed using intensity-modulated helical tomotherapy (HT) were quantitatively investigated. Step-and-shoot intensity-modulated radiotherapy (SaS-IMRT) was used as a benchmark. METHODS: Sixteen patients separated into two groups with primary hepatocellular carcinomas or metastatic liver tumours previously treated using SaS-IMRT were examined and re-planned by HT. The dosimetric indices used included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), max/mean dose, quality index (QI), normal tissue complication probability (NTCP), V(30 Gy), and V(50%) for the specified organs at risk (OARs). The monitor units per fraction (MU/fr) and delivery time were also analysed. RESULTS: For the single tumour group, both planning systems satisfied the required PTV prescription, but no statistical significance was shown by the indexes checking. A shorter delivery time and lower MU/fr value were achieved by the SaS-IMRT. For the group of multiple tumours, the average improvement in CI and HI was 14% and 4% for HT versus SaS-IMRT, respectively. Lower V(50%), V(30 Gy) and QI values were found, indicating a significant dosimetric gain in HT. The NTCP value of the normal liver was 20.27 +/- 13.29% for SaS-IMRT and 2.38 +/- 2.25% for HT, indicating fewer tissue complications following HT. The latter also required a shorter delivery time. CONCLUSIONS: Our study suggests dosimetric benefits of HT over SaS-IMRT plans in the case of multiple liver tumours, especially with regards sparing of OARs. No significant dosimetric difference was revealed in the case of single liver tumour, but SaS-IMRT showed better efficiency in terms of MU/fr and delivery time.
Asunto(s)
Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Estudios Retrospectivos , Tomografía Computarizada EspiralRESUMEN
PURPOSE: The study evaluates and quantifies the potential dosimetric gains of helical tomotherapy (HT) versus step-and-shoot intensity-modulated radiotherapy (SaS-IMRT) for nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Twenty consecutive NPC patients curatively treated by HT were examined. Each case was planned by HT and SaS-IMRT (ADAC Pinnacle(3)) planning system, respectively. Dose plans were compared using dose volume histograms (DVH), conformity index (CI), homogeneity index (HI), and minimal dose to 1cc (D(min_1cc)) of the planned target volume (PTV) and a comprehensive quality index (CQI) of ten organs at risk (OARs). The prescribed dose/fractionation was 72Gy to the PTV, 64.8Gy to the elective PTV, and 54Gy to the clinically negative neck region. The plan of 54Gy to the PTV (PTV(54)) was used to evaluate the CI and HI in the target. The cumulative doses of the three PTV plans to the OARs were calculated. RESULTS: We observed the HT plans significantly improved the CI (improvement ratio: 11.9+/-5.5%) and HI (improvement ratio: 8.8+/-1.5%) of the PTV(54) compared with SaS-IMRT plans. In addition, the mean/maximal dose of most of the OARs except chiasm was significantly reduced in HT plans, with the CQI of 0.92+/-0.08. A negative result of HT in chiasm was observed but only significantly revealed in cases without skull base infiltration. CONCLUSIONS: A dosimetric gain in CI and HI of PTV and sparing of OARs was significantly obtained in HT versus SaS-IMRT plans in NPC patients. Whether such dosimetric superiority in HT could transfer into clinical advantages needs further investigation.
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Carcinoma/diagnóstico por imagen , Carcinoma/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Tomografía Computarizada Espiral , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Resultado del TratamientoRESUMEN
OBJECTIVE: To determine whether immunocytochemistry (ICC) for HER2 on ThinPrep (TP)-processed breast fine needle aspiration biopsies (Cytyc Corp., Boxborough, Massachusetts, U.S.A.) is comparable to the findings of immunohistochemistry on corresponding surgically removed tissue. STUDY DESIGN: Immunostaining was performed on 63 malignant breast fine needle aspirates and compared to immunostaining on paraffin sections (PSs) from the subsequent biopsies. The HercepTest (Dako, Carpinteria, California, U.S.A.) and TAB250 antibodies were utilized. Cases in which the TP and paraffin HER2 results did not correlate were further assessed for gene amplification by differential polymerase chain reaction (dPCR). RESULTS: HER2 overexpression was found in 9 of the 63 cases (14%). TAB250 had higher specificity on PS versus TP (P = .008), and TAB250 had higher specificity on PS versus the HercepTest on PS and TP (P = .004 and .0001, respectively). CONCLUSION: HER2 immunostaining with both the HercepTest and TAB250 on TP is unreliable due to low specificity (72% and 83% for HercepTest and TAB250, respectively). However, both antibodies have high sensitivity (89% and 100%, respectively); suggesting that this method may have some utility as a preliminary screening test for HER2 status. Negative HER2 staining by ICC is highly predictive of the absence of HER2 overexpression, whereas positive HER2 staining on TP would require further validation by either dPCR of fluorescence in situ hybridization.
Asunto(s)
Biopsia con Aguja Fina/normas , Neoplasias de la Mama/patología , Carcinoma/patología , Inmunohistoquímica/normas , Receptor ErbB-2/análisis , Anticuerpos , Biopsia con Aguja Fina/estadística & datos numéricos , Neoplasias de la Mama/metabolismo , Carcinoma/metabolismo , Femenino , Humanos , Inmunohistoquímica/estadística & datos numéricos , Variaciones Dependientes del Observador , Patología Quirúrgica/normas , Patología Quirúrgica/estadística & datos numéricos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Adhesión del Tejido/normasRESUMEN
PURPOSE: To evaluate the health-related quality of life (HR-QOL) of nasopharyngeal cancer (NPC) patients with cancer-free survival after treatment and to investigate the factors correlated with their HR-QOL. METHODS AND MATERIALS: One hundred eighty-two NPC patients with cancer-free survival of more than 2 years after treatment were enrolled in the study. Data from the same number of people without a history of cancer, who had come to the hospital for health checkups, were also collected for comparison. The Chinese SF-36 questionnaire and nine items about head-and-neck functional impairments (HNFI) were self-reported by all participants at the clinics. Data relating to sociodemographic factors, cancer stage, and treatment of NPC survivors were analyzed. RESULTS: Psychometric tests revealed the excellent internal reliability (Cronbach's alpha: 0.87-0.96) and discriminative validity of the Chinese SF-36 used in Taiwan. Most functional domains of the Chinese SF-36 and all nine HNFI items were significantly worse in NPC survivors than in control subjects. No cancer or treatment-related variables significantly correlated with any functional domains of SF-36 or any items of HNFI for NPC survivors. Economic status, educational level, occupational status, and the number of comorbidities were the variables that significantly correlated with most functional domains of SF-36 for NPC survivors. Patients with more sufficient economic status, higher educational levels, with employment, or without comorbidity tended to enjoy better HR-QOL as detected by the SF-36. Salivation, hearing, and swallowing dysfunctions were the top three HNFI that disturbed NPC survivors. Economic status remained the most significant variable correlated with HNFI, including salivation, swallowing, neck stiffness, taste, and phonation. Survivors with better economic status reported less severe HNFI. CONCLUSIONS: NPC survivors had worse HR-QOL than healthy control subjects in the study. Socioeconomic status was the most significant variable that correlated with the HR-QOL of NPC survivors. This result might indicate that patients' superior individual characteristics and financial resources are important variables determining their ability to cope with cancer and treatment complications affecting their HR-QOL.