Effect of tertiary multileaf collimator (MLC) on foetal dose during three-dimensional conformal radiation therapy (3DCRT) of a brain tumour during pregnancy.

BACKGROUND AND PURPOSE: The aim of this work was to measure the dose to foetus both in vivo and in vitro during three-dimensional conformal radiation therapy (3DCRT) in a pregnant patient with a pituitary adenoma. The study was then extended to assess the components contributing to the foetal dose such as collimator scatter, internal scatter, head leakage, wedge scatter and multileaf collimator (MLC) effect. PATIENTS AND METHODS: A 30-year-old pregnant woman with a non-functioning pituitary macroadenoma was planned for 3DCRT with 6MV X-ray using four equally weighted MLC-shaped non-coplanar wedged portals. In vivo dosimetry was carried out using thermoluminescent (TL) phosphor powder, which was placed at different positions on the patient, corresponding to different locations in the uterus and also at external os. In vitro measurements were also performed on a simulated phantom using the same set-up parameters and beam arrangement to verify the in vivo measured dose. Experiments were carried out to measure the respective contributions of different components towards peripheral dose. RESULTS: In vitro measured dose to foetus was found to be slightly more than that of in vivo measurement with a maximum of 0.044% of the prescribed dose of 45Gy, which corresponded to 0.0199+/-0.0008Gy. Thermoluminescence dosimeter (TLD) kept at the external os of the patient showed a dose of 0.031% of the prescribed dose. Among the various components of the peripheral dose (foetal dose) measured, head leakage was found to be the leading cause contributing 52%, followed by wedge scatter (31%), collimator scatter (14%) and internal scatter (13%). The use of MLC reduced not only the volume of normal brain irradiation as compared to open fields but also the peripheral dose by 10%. CONCLUSION: Radiotherapy of brain tumours during pregnancy poses a unique clinical situation and decisions to deliver radiotherapy should be taken after detailed in vitro and in vivo dosimetric measurements. Our findings suggest that the beam arrangement using 3-4-fields generally used for 3DCRT of brain tumour with MLC for optimal coverage can be employed for pregnant patients even in early trimester. A possible increase in foetal dose from wedges to a large extent can be compensated with the use of MLC.     

Competing causes of death and second primary tumors in patients with locoregionally advanced head and neck cancer treated with chemoradiotherapy.

PURPOSE: The purpose of this retrospective analysis was to evaluate the emergence of second primary malignancies and the contribution of different causes of death to the outcome of patients with locoregionally advanced head and cancer receiving primary chemoradiotherapy. EXPERIMENTAL DESIGN: We studied 324 patients with stage IV squamous cell head and neck cancer who were enrolled on five consecutive multicenter Phase II studies of concurrent chemoradiotherapy. All of the regimens included concurrent 5-fluorouracil and hydroxyurea on an alternate week schedule with radiotherapy, either alone (FHX) or with cisplatin (C-FHX) or paclitaxel (T-FHX). The cumulative incidence of second primary tumors or death from any cause was estimated using methods of competing risk analysis. RESULTS: Median follow-up of surviving patients was 5.2 years (2-10.6 years). The 5-year overall survival and progression-free survival of the cohort were 46% and 65%, respectively. Causes of death and median time of occurrence were as follows: disease (n = 88; 1.5 years), treatment-associated acute or late complications (n = 30; 4 months), second primary tumors (n = 18; 3.5 years), comorbidities (n = 41; 1.9 years), and unknown (n = 20; 5.1 years). Predominant causes of death from comorbidities were cardiac and respiratory illnesses. Twenty-six patients (8%) developed a second primary tumor at a median time of 2.8 years (4 months to 10 years). The cumulative incidence of second primary tumors was 5%, 7%, and 13% at 3, 5, and 10 years, respectively. The most frequent site of second primaries was the lung (n = 13), followed by the esophagus (n = 3) and head and neck (n = 2) CONCLUSIONS: Patients with locoregionally advanced head and neck cancer treated with concurrent chemoradiotherapy are potentially curable but face significant risks of mortality from causes other than disease progression. Ameliorating toxicity, and implementing secondary screening and chemoprevention strategies are major goals in the management of head and neck cancer.     

Hemimegalencephaly with tuberous sclerosis: A longitudinal imaging study

Hemimegalencephaly is a rare cerebral malformation characterized by asymmetry of the hemispheres and cortical dysplasias. We report clinical and imaging findings in a child with hemimegalencephaly involving the right cerebral hemisphere with associated manifestations of tuberous sclerosis complex. Gross abnormal myelination pattern and gyral abnormalities were seen in the enlarged hemisphere. Subsequent scans showed atrophy of the frontoparietal region in the enlarged hemisphere and normal growth of the opposite hemisphere exceeding the size of the abnormal hemisphere in the frontoparietal region. A few white‐matter lesions that were seen in the normal hemisphere on neonatal scan were difficult to appreciate on subsequent MR studies. The white‐matter lesions were better seen in the neonatal period, whereas cortical tubers were better detected at a later age.     

Weekly carboplatin and paclitaxel followed by concomitant paclitaxel, fluorouracil, and hydroxyurea chemoradiotherapy: curative and organ-preserving therapy for advanced head and neck cancer.

PURPOSE: The paclitaxel, fluorouracil, and hydroxyurea regimen of paclitaxel, infusional fluorouracil, hydroxyurea, and twice-daily radiation therapy (TFHX) administered every other week has resulted in 3-year survival rates of 60% of stage IV patients. Locoregional and distant failure rates were 13% and 23%, respectively. To reduce distant failure rates, we added a brief course of induction chemotherapy to TFHX. PATIENTS AND METHODS: Sixty-nine patients received six weekly doses of carboplatin (AUC2) and paclitaxel (135 mg/m2) followed by five cycles of TFHX. RESULTS: Ninety-six percent had stage IV disease. Response to induction chemotherapy was partial response 52% and complete response (CR) 35%. Symptomatically, there was a significant reduction in mouth and throat pain. The most common grade 3 or 4 toxicity was neutropenia (36%). Best response following completion of TFHX was CR in 83%. Toxicities of TFHX consisted of grade 3 or 4 mucositis (74% and 2%) and dermatitis (47% and 14%). At a median follow-up of 28 months, locoregional or systemic disease progression were each noted in five patients. The overall 3-year progression-free survival was 80% (95% confidence interval [CI], 71% to 90%), and the 2- and 3-year overall survival rates were 77% (95% CI, 66% to 87%) and 70% (95% CI, 59% to 82%), respectively. At 12 months, five patients were completely feeding-tube dependent. CONCLUSION: Administration of carboplatin and paclitaxel before TFHX chemoradiotherapy results in high response activity and may decrease distant failure rates. Overall survival, progression, and organ preservation/functional outcome data support definitive evaluation of this approach.     

Imaging in isolated sacral tuberculosis: a review of 15 cases

Objective. To review imaging studies of isolated involvement of the sacrum due to tuberculosis and determine the role of imaging in the diagnosis and management of these patients. Design and patients. A retrospective analysis of 15 cases of isolated sacral tuberculosis imaged with MR imaging was performed. The CT images were also reviewed where available, and the various lesion characteristics were identified. We also reviewed the medical records in an attempt to determine the impact of the imaging studies on the management of these patients. Results. Fifteen patients (5 male, 10 female) presented with symptoms of 3–15 months’ duration. Chronic localized backache with muscle spasm was the commonest presenting symptom; discharging sinuses with abscess formation was found in six patients, five of whom were children. MR imaging of the sacrum revealed a hypointense marrow signal on T1-weighted images and hyperintense signal on T2-weighted images in 14 of 15 patients, the S2 vertebra being always involved. CT revealed osteolytic changes in the sacrum in all the five patients in whom CT was performed. All patients showed marked clinical improvement within 1 year of anti-tuberculous chemotherapy. Conclusion. Isolated tuberculosis of the sacrum is uncommon but should be suspected in patients presenting with chronic low backache or children with discharging sinuses/abscesses and showing sacral destruction on CT or MR imaging. MR imaging can identify cases and enables early institution of anti- tuberculous chemotherapy. Received: 31 August 1999 Revision requested: 1 November 1999 Revision received: 27 March 2000 Accepted: 14 April 2000     

Macroglossia due to venous malformation

Massive vascular malformation involving tongue can cause significant functional impairment. In this report we describe a rare case of extensive venous malformation involving tongue leading to obstructive sleep apnoea, inability to speak, eat, severe discomfort due to exposure induced dryness and ulceration. Multimodality treatment approach comprising of sclerotherapy, electrocautery and radiation therapy was used in this case.     

Levonorgestrel-releasing intrauterine system vs. transcervical endometrial resection for dysfunctional uterine bleeding.

OBJECTIVE: To compare the acceptability, efficacy, adverse effects, and user satisfaction of a levonorgestrel intrauterine system (LNG-IUS) and transcervical resection of the endometrium (TCRE) for the treatment of dysfunctional uterine bleeding. METHOD: Of 50 women with a pictoral blood loss assessment chart (PBAC) score of 100 or greater, 25 had a LNG-IUS inserted (Mirena; Schering, Berlin, Germany) and 25 underwent TCRE. Procedure-related complications, PBAC score, hemoglobin levels, adverse effects, and rates of acceptability and satisfaction were recorded at 3-month intervals for a period of 12 months. RESULTS: At the end of 1 year there were a 97% and a 94% reduction in menstrual blood loss in the LNG-IUS and TCRE groups, respectively, and hemoglobin concentration had increased by 5.5% in the LNG-IUS group and 5.2% in the TCRE group. Adverse effects were similar in both groups except for systemic effects, which were seen only in the LNG-IUS group. Satisfaction rates were about 80% in the 2 groups. CONCLUSION: Both treatments were found to be equally effective but LNG-IUS placement requires less operator skill and entails no operative hazards, and the device provides effective contraception.