J. Quera

Five-year outcomes, cosmesis, and toxicity with 3-dimensional conformal external beam radiation therapy to deliver accelerated partial breast irradiation.

PURPOSE To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT). METHODS AND MATERIALS 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor. RESULTS The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P<.01). Late skin toxicity was no worse than grade 2 in either group, without significant differences between the 2 groups. In the ipsilateral breast, the areas that received the highest doses (ie, the boost or quadrant) showed the greatest loss of elasticity. WBI resulted in a greater loss of elasticity in the high-dose area compared with APBI (P<.05). Physician assessment showed that >75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups. CONCLUSIONS APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with conventional WBI.

Relationship Between Radiation-Induced Apoptosis of T Lymphocytes and Chronic Toxicity in Patients With Prostate Cancer Treated by Radiation Therapy: A Prospective Study

PURPOSE To assess the correlation of radiation-induced apoptosis in vitro of CD4 and CD8 T lymphocytes with late toxicity of prostate cancer patients treated with radiation therapy. METHODS AND MATERIALS 214 patients were prospectively included in the study. Peripheral blood was drawn from patients before treatment and irradiated with 8 Gy. The percentage of CD4+ and CD8+ T lymphocytes that underwent radiation-induced apoptosis was assessed by flow cytometry. Toxicity and mortality were correlated in 198 cases with pretreatment apoptosis and clinical and biological variables by use of a Cox proportional hazards model. RESULTS The mean percentage of CD4+ and CD8+ T lymphocyte radiation-induced apoptosis was 28.58% (±14.23) and 50.76% (±18.9), respectively. Genitourinary (GU) toxicity was experienced by 39.9% of patients, while gastrointestinal (GI) toxicity was experienced by 19.7%. The probability of development of GU toxicity was nearly doubled (hazard ratio [HR] 1.99, P=.014) in those patients in whom the percentage of in vitro radiation-induced apoptosis of CD4+ T-lymphocytes was ≤28.58%. It was also almost double in patients who received doses ≥50 Gy in 65% of the bladder volume (V65 ≥50) (HR 1.92, P=.048). No correlation was found between GI toxicity and any of the variables studied. The probability of death during follow-up, after adjustment for different variables, was 2.7 times higher in patients with a percentage of CD8+ T lymphocyte apoptosis ≤50.76% (P=.022). CONCLUSIONS In conclusion, our study shows, in the largest prospective cohort of prostate cancer patients undergoing radiation therapy, that in vitro radiation-induced apoptosis of CD4+ T lymphocytes assessed before radiation therapy was associated with the probability of developing chronic GU toxicity. In addition, the radiation dose received in the urinary bladder (V65 ≥50) affected the occurrence of GU toxicity. Finally, we also demonstrate that radiation-induced apoptosis of CD8+ T lymphocytes was associated with overall survival, although larger series are needed to confirm this finding.

Long-term results and prognostic factors of patients with cervical carcinoma treated with concurrent chemoradiotherapy

Aims and backgroundTo evaluate the predictive factors of recurrence in cervical cancer treated with radical radiochemotherapy.MethodsA retrospective analysis of 56 women was performed. Response was assessed using the RECIST response. Overall survival and disease-free survival curves were estimated by the Kaplan-Meier method and the Cox proportional hazards model was used to analyse predictors of recurrence.ResultsLocal recurrence was documented in 16 patients and distant metastases in 15. The Kaplan-Meier survival probabilities were 95.1±6.4% at 3 years and 80.4±13.1% at 5 years and the Kaplan-Meier curve values for disease-free survival were 60.3±14.3% at 3 years and 53.0±15.7% at 5 years. Thirty-five patients were alive and 21 patients died, 19 from metastatic disease and 2 from other causes. Complete response after chemoradiation therapy, squamous cell carcinoma and tumour size ≤4 cm were significantly associated with outcome. In the Cox regression model, tumour size >4 cm (hazard ratio 7.48; 95% CI 2.71–20.6; p<0.001) and partial response (hazard ratio 7.09; 95% CI 2.82–17.8; p<0.001) were predictive factors for disease-free survival and partial response (hazard ratio 3.7; 95% CI 1.3–10.1; p<0.001) and non-squamous cell carcinoma (hazard ratio 3.5; 95% CI 1.2–9.7; p<0.001) were predictive factors for overall survival.ConclusionsNon-squamous histology and partial response were independent prognostic factors for overall survival and tumour size and partial response were independent prognostic variables for 5-year disease survival.

EP-1221: Accelerated hypofractionated three-dimensional conformal radiation therapy (AHRT) for NSCLC

Results: The main result was the reduction in primary and nodal volumes due to better definition of lung mass and nearby lung Collapse , the latter could be easily defined in 14 cases on the DW-MRI vs. 7 cases only by CT scans (P=0.016). Median GTV total (sum of 1ry and nodal GTV), on MRI Diffusion compared to that on the CT scan was 354 and 386 cm3 respectively (P= 0.009). In 15 cases, a mean decrease in the GTV total of 34% ±56% (median, 9%; range, 0.232.5%) by using DW-MRI. only in three other cases a mean increase in the GTV total of 12.7% ±14.9% (median, 9.7%; range, 0.4221%). was found. The median PTVs on the CT scans vs. the MRI Diffusion were 1623 (range, 493–2965 cm3) & 1419 (range, 542–3158 cm3) respectively which was statistically non significant (P= 0.391).