Palliative spleen irradiation: can we standardize its technique?

PURPOSE To explore the pattern of practice of palliative splenic irradiation (PSI) at the National Cancer Institute (NCI), Cairo University. PATIENTS AND METHODS The medical records of patients referred for PSI during the time period from 1990 to 2005 were retrospectively reviewed. We compared the three most common planning techniques (two parallel opposing, single direct field, anterior and lateral fields). RESULTS Eighteen patients who received PSI were identified. Thirteen patients were diagnosed as CML and 5 as CLL. The mean age of the patients was 44 (+/-16) years and the majority were men (60%). Spleen enlargement was documented in all cases. The single direct anterior field was the most commonly used technique. The dose per fraction ranged from 25 cGy to 100 cGy. The total dose ranged from 125 cGy to 1200 cGy and the median was 200 cGy (mean 327 cGy). There was no significant difference between CML and CLL patients regarding the dose level. Three out of 5 CLL patients and only one out of 13 CML patients received re-irradiation. All patients showed subjective improvement regarding pain and swelling. There was a significant increase in the hemoglobin level and a significant decrease in the WBC count. The single direct field shows variations in the dose from 56 to 102%; however, it is the simplest and the best regarding the dose to the surrounding normal tissues especially the kidney and the liver. CONCLUSION PSI has a significant palliative benefit. Although the most widely accepted technique is the 2 parallel opposing anterior-posterior fields, single anterior field is also considered as a suitable option. Higher doses are needed for CLL patients compared to CML patients.