Azza Nasr

Dosimetric prospective study comparing 2D and 3D planning for irradiation of supraclavicular and infraclavicular regions in breast cancer patients

PURPOSE The purpose of this study is to compare 2D plan and 3D plan regarding coverage of the target (supraclavicular and infraclavicular regions) and dose reaching the risk organs (using mean DVH). Depending on the results of this study, modifications can be made to the 2D conventional planning of supraclavicular and infraclavicular regions in order to achieve better coverage of the target tissues. MATERIALS AND METHODS This is a dosimetric study carried out at the radiation oncology department in NCI-Cairo University in the period from January 2012 to October 2012, on 15 patients with breast cancer who are eligible for supraclavicular and infraclavicular irradiation. For All patients, a 2D and a 3D plan were done. RESULTS We found that the coverage of the supraclavicular and infraclavicular regions and the chest wall or breast together with levels I and II axilla (PTV) were significantly better with the 3D technique with less over dose than the 2D technique. That difference was highly significant and was most evident in MRM cases. Also we found that organs at risk received a dose in the 3D technique that was more than that received in the 2D technique, again that difference was highly significant and was also most evident in MRM cases but all doses were still within tolerance. CONCLUSIONS From the present study we concluded that the coverage of the supraclavicular and infraclavicular PTV is significantly worse with the 2D technique using a single oblique field at a fixed depth of 3 cm for all patients despite their different builts.

Outcome of cervix uteri cancer patients: Clinical treatment results and toxicity profile in a retrospective study from Saudi Arabia

This study evaluated the survival outcome, pattern of failure and prognostic factors in cervix uteri cancer patients.

A Clinico-Epidemilogical Study of Cases of Locally Advanced Non-Small Cell Lung Cancer (NSCLC) that Received Radiotherapy at NCI Cairo in the Period from 2001-2010

Purpose: This work was to study the clinic-epidemiological characteristics of patients with locally advanced NCSLC and to analyze their prognostic factors and also the results of different treatment modalities for local control and their effect on overall survival (OAS). Materials and methods: This is a retrospective study included 121 patients with primary locally advanced NSCLC diagnosed between 2001 and 2010 at the radiotherapy department, National Cancer Institute, Cairo University, Egypt. Results: The study showed significant correlation between the tumor size ≤ 7 cm, old age >60, moderately differentiated tumors G2 and treatment outcomes; better locoregional control and better survival rates. On the opposite side poorly differentiated tumors G3, tumor size >7 cm had the worst locoregional control and survival rates. The study also showed significant statistical correlation between treatment modality, locoregional control and survival rates. Patients who were treated by either concomitant chemo-radiotherapy or sequential chemoradiotherapy had better local control compared to other patients who were treated by radical radiotherapy, and they also had the best survival rates among all the other treatment groups. The average 6 months OAS rates for all studied patients were 60.3% while 12 months survival rates were 38.8%. The median OAS was 7 months. The data was summarized by descriptive statistics [i.e., mean, standard deviation (SD), frequencies]. Mean values and standard deviation were compared using simple T-test (2 variables). Percentages were compared using Chi-square test or Fisher’s exact test. Kaplan-Meier test was used for predictive survival rates. Conclusions: From the present study, we concluded that concomitant chemradiotherapy is the treatment of choice for locally advanced non small cell lung cancer; also we concluded that better performance status and higher hemoglobin levels have better treatment outcome in these cases.

Dosimetric analytic comparison of inverse and forward planned IMRT techniques in the treatment of head and neck cancer

PURPOSE Our aim was to investigate if, and to what degree, improvements of IMRT treatment plans generated by forward planning can be achieved with an inverse planning strategy for treatments of head and neck cancer. METHODS Between June 2007 and April 2008, 19 patients with head-and-neck cancers were treated at KAAH and Oncology Center Jeddah, using forward planning intensity modulated radiation therapy (FP-IMRT). They received thirty fractions over six weeks, to simultaneously deliver 66 Gy to the gross tumor (CTV1), 60 Gy to the soft tissue and nodes adjacent to the previous volume (CTV2), and 54 Gy to elective nodes (CTV3). These are biologically equivalent to 70, 60, and 50 Gy, if given 2 Gy per fraction. These were retrospectively re-planned with an inverse planning algorithm (IP-IMRT). The main objective of the optimization process was sparing of the parotid glands, spinal cord, and brainstem beside adequate treatment of the planning target volume. RESULTS Having 95% and 98% of CTV1 to receive at least 95% and 90% of prescribed dose respectively was fulfilled in all cases in both groups with higher figures in group B (IP-IMRT) than in group A (FR-IMRT), more obvious in CTV2 and CTV3. The average maximum dose to the spinal cord was 45.1 Gy in group A, and 41.6 Gy in group B. The mean dose of both parotid glands was kept below 26 Gy in four patients in group A, but in all cases in group B. CONCLUSION IP-IMRT selectively spared critical organs to greater degree with better target coverage and should be considered the standard of treatment in head and neck tumors.