MATERIALS AND METHODS: This retrospective study was conducted at the Department of Radiotherapy and Oncology, Hospital Kuala Lumpur, Malaysia. All patients with histologically confirmed recurrent NPC in the absence of distant metastasis treated in the period 1997-2010 were included in this study. These patients were treated with ICBT alone or in combination with external beam radiotherapy (EBRT). Treatment outcomes measured were local recurrence free survival (LRFS), disease free survival (DFS) and overall survival (OS).
RESULTS: Thirty three patients were eligible for this study. The median age at recurrence was 56 years with a median time to initial local recurrence of 27 months. Majority of patients were staged as rT1-2 (94%) or rN0 (82%). The proportion of patients categorised as stage III-IV at first local recurrence was only 9%. Twenty one patients received a combination of ICBT and external beam radiotherapy while 12 patients were treated with ICBT alone. Median interval of recurrence post re-irradiation was 32 months (range: 4-110 months). The median LRFS, DFS and OS were 30 months, 29 months and 36 months respectively. The 5 year LRFS, DFS and OS were 44.7%, 38.8% and 28.1% respectively. The N stage at recurrence was found to be a significant prognostic factor for LRFS and DFS after multivariate analysis. Major late complications occurred in 34.9% of our patients.
CONCLUSIONS: Our study shows ICBT was associated with a reasonable long term outcome in salvaging recurrent NPC although major complications remained a significant problem. The N stage at recurrence was a significant prognostic factor for both LRFS and DFS.
MATERIALS AND METHODS: This retrospective cross sectional study looked at prostate cancer patients seen in the Urology Departments in 2 tertiary centres over the 11 year period starting from January 2000 to May 2011. Patient demographic data, levels of PSA at diagnosis, Gleason score for the biopsy core, T-staging as well as the lymph node status were recorded and analysed.
RESULTS: 258 men were included. The mean age of those 90 men (34.9%) with bone metastasis was 69.2 ± 7.3 years. Logistic regression found that PSA level (P=0.000) at diagnosis and patient's nodal-stage (P=0.02) were the only two independent variables able to predict the probability of bone metastasis among the newly diagnosed prostate cancer patients. Among those with a low PSA level less than 20 ng/ml, and less than 10 ng/ml, bone metastasis were detected in 10.3% (12 out of 117) and 9.7% (7 out of 72), respectively. However, by combining PSA level of 10 ng/ml or lower, and nodal negative as the two criteria to predict negative bone scan, a relatively high negative predictive value of 93.8% was obtained. The probability of bone metastasis in prostate cancer can be calculated with this formula: -1.069+0.007(PSA value, ng/ml) +1.021(Nodal status, 0 or 1)=x Probability of bone metastasis=2.718 x/1+2.718 x.
CONCLUSION: Newly diagnosed prostate cancer patients with a PSA level of 10 ng/ml or lower and negative nodes have a very low risk of bone metastasis (negative predictive value 93.8%) and therefore bone scans may not be necessary.
MATERIALS AND METHODS: Data from 10 consecutive patients treated with IMRT from June-October 2011 in Penang General Hospital were collected retrospectively for analysis. For each patient, dose volume histograms were generated for both the IMRT and 3DCRT plans using a total dose of 70Gy. Comparison of the plans was accomplished by comparing the target volume coverage (5 measures) and sparing of organs at risk (17 organs) for each patient using both IMRT and 3DCRT. The means of each comparison target volume coverage measures and organs at risk measures were obtained and tested for statistical significance using the paired Student t-test.
RESULTS: All 5 measures for target volume coverage showed marked dosimetric superiority of IMRT over 3DCRT. V70 and V66.5 for PTV70 showed an absolute improvement of 39.3% and 24.1% respectively. V59.4 and V56.4 for PTV59.4 showed advantages of 18.4% and 16.4%. Moreover, the mean PTV70 dose revealed a 5.1 Gy higher dose with IMRT. Only 4 out of 17 organs at risk showed statistically significant difference in their means which were clinically meaningful between the IMRT and 3DCRT techniques. IMRT was superior in sparing the spinal cord (less 5.8Gy), V30 of right parotid (less 14.3%) and V30 of the left parotid (less 13.1%). The V55 of the left cochlea was lower with 3DCRT (less 44.3%).
CONCLUSIONS: IMRT is superior to 3DCRT due to its dosimetric advantage in target volume coverage while delivering acceptable doses to organs at risk. A total dose of 70Gy with IMRT should be considered as a standard of care for radical treatment of NPC.