Malignant astrocytoma arising 10 years after combined treatment of craniopharyngioma.

Craniopharyngioma is the third most common intracranial tumor in childhood. Following surgery, virtually all patients present with hypopituitarism and are at considerable risk of tumor recurrence. Secondary tumors, however, are rare, occurring usually 10 years after diagnosis and associated with poor prognosis. We report on a 5 year-old boy in whom craniopharyngioma was diagnosed due to unilateral visual loss. After surgery he underwent conventional radiation therapy with a total tumor dose of 55 Gy, and had hormonal support with DDAVP, thyroxine, and a variable dose of hydrocortisone. Growth velocity declined slowly in the first 4 years, but improved later on again without GH therapy despite abnormal provocative tests. At the age of 15 years he developed peripheral facial nerve palsy due to a malignant astrocytoma (WHO grade III/IV). Repeated conventional radiation therapy with an additional stereotactic boost and chemotherapy could not prevent the fatal outcome. This observation may temper the use of radiosurgery in benign intracranial tumors.

[Prophylaxis of heterotopic ossification in hip revisions with 7 Gy single-dose radiation]. / Ossifikationsprophylaxe bei Hüft-Wechseloperationen mit 7-Gy-Einzelbestrahlung.

AIM OF STUDY: Radiation therapy is an established method for the prevention of heterotopic ossification. The aim of this study was to assess whether radiation therapy is also effective in revision arthroplasties. METHOD: 143 hips were irradiated with 7 Gy anterior-posterior applied single dose radiation, on one of the first four days after revision surgery. RESULTS: After an average follow-up of 18 months, 107 hips were evaluated radiographically using Brooker's criteria. In comparison to the immediate postoperative findings (26 % showed no heterotopic ossification, 66 % had Brooker I, 5 % Brooker II, and 3 % Brooker III), at final follow-up 19 % showed no heterotopic ossification, 66 % had Brooker I, and 7.5 % Brooker II and III. New ossification or an increase of one grade was found in 12 %, of two grades in 4 %. Grade 0 showed significantly more ossifications. Gender (p = 0.43), age (p = 0.43), the type of revision surgery (p = 0.36), the day of radiation (1st day vs. 2nd, 3rd, 4th day; p = 0.46) had no significant influence on this increase. There was no correlation between pain score and Brooker grades (p = 0.755). There was a significantly (p < 0.01) negative correlation (r = - 0.31) between the Brooker grades and flexion. CONCLUSION: Radiation therapy with 7 Gy single dose effectively prevents the new formation of heterotopic ossification or the progression of ossifications after revision surgery. To prevent a decrease in the range of motion due to HO after revision surgery, HO should be removed intraoperatively.

Malignant glioma as a secondary malignant neoplasm after radiation therapy for craniopharyngioma: report of a case and review of reported cases.

BACKGROUND: The development of a secondary neoplasm in childhood cancer survivors attains growing importance due to the reported excellent survival and therefore the long exposure to potentially carcinogenic effects of treatment. CASE REPORT: We report a 14-year-old girl in whom a large craniopharyngioma (CP) was diagnosed. After surgery, radiation therapy (RT) was given for residual tumour. Discrete progression necessitated further surgery, resulting in permanent tumour control. Soon after the second surgery hypothalamic-pituitary dysfunction developed together with obesity. Supportive hormone therapy was initiated. Growth hormone (GH) therapy was also given for 15 months. Four years after the diagnosis, a cerebropontine anaplastic astrocytoma WHO grade III was detected, with the main lesion being at the dorsal edge of the irradiated area. The girl died 1 month later from this secondary presumably radiation-induced tumour. Only recently a second child with RT for a CP was diagnosed with malignant glioma in our hospital. CASE REPORTS IN THE LITERATURE: 12 other cases of malignant glioma have been reported after RT for CP. Including our present cases, the mean latency period was 10.7 years (median 9.6 years). However, the shortest latency periods were found in patients who had received GH therapy. In numerous cases, the secondary tumour was seen at the edge of the irradiated volume, and not in the region with the highest absorbed dose. CONCLUSIONS: Therapy-induced secondary gliomas after treatment of CP or other intracranial tumours are rare but dramatic late events with a very poor prognosis. Including our own 2 patients, we reviewed 14 cases of CP with occurrence of a secondary, probably radiation-induced malignant glioma. The short latency periods for patients treated with GH is remarkable. We therefore suspect that GH therapy may accelerate the development of a secondary brain tumour. We are reluctant to recommend GH therapy in conventionally irradiated CP patients. In order to seriously answer the questions about therapy-induced secondary neoplasms, a life-long follow-up is mandatory for all patients who are survivors of childhood cancer.

Radiotherapy for lung cancer: target splitting by asymmetric collimation enables reduction of radiation doses to normal tissues and dose escalation.

PURPOSE: This study was performed to develop a method of reducing the radiation doses to normal thoracic tissues, increasing the target dose, especially in the primary radiotherapy of non-small cell lung cancer (NSCLC), and to evaluate acute/subacute toxicity of dose escalation. METHODS AND MATERIALS: From December 1195 to March 1998, the technique of target splitting has been applied to 58 patients. In this period, 30 patients were treated with doses > 80 Gy (ICRU-specification, mean 85.1 Gy, range 80. 1-90.2 Gy). The target volume is split into a cranial part (e.g., upper mediastinum) and a caudal part (e.g., primary tumor and middle mediastinum). Both volumes are planned and treated independently, using conformal irradiation techniques for both parts with half-collimated fields to prevent over- or underdosage in the junction plane. After fine-adjustment of the jaws, a verification film, exposed in a polymethylmethacrylate (PMMA) phantom, demonstrates the homogeneity of dose in the entire target volume. For comparison with conventional techniques, planning to identical doses is performed for 5 patients. Dose-volume histograms (DHVs) for normal lung tissue are presented for both methods. RESULTS: The irradiated volume of normal tissue of the ipsilateral lung can be lowered at dose levels > or = 65, > or =45 Gy, and > or = 20 Gy to values of 37% (range 25-54%), 49% (range 46-54%), and 86% (range 55-117%), respectively. Other organs at risk, such as heart or esophagus, can also be spared significantly. Only 1 patient showed a transient grade 3 toxicity (pneumonitis), and there where no grade 4 acute/subacute side-effects. Two patients with Stage III A central tumors in close proximity to the large vessels died due to a pulmonary hemorrhage 2 and 4 months after therapy, respectively. No patient developed esophagitis. Antimycotic prophylaxis for esophagitis and posttherapeutic steroid prophylaxis for pneumonitis for several weeks were routinely used. CONCLUSION: The technique of target splitting by asymmetric collimation helps to increase conformation, and thus enhances the sparing of normal tissues. It can be used whenever there is a marked difference in the shape of the planning target volume (PTV) in a cranio-caudal direction. This technique can principally be handled with 2D-planning systems, because it is coplanar. We consider target splitting as an important tool for dose escalation in the primary radiotherapy of NSCLC, that should also be used for other lung cancer patients necessitating moderate doses only.

Quality assurance in breast cancer brachytherapy: geographic miss in the interstitial boost treatment of the tumor bed.

PURPOSE: To assess the role of geographic misses in the interstitial boost treatment of breast cancer patients and to evaluate methods of optimizing breast implants in design, performance, and dosimetry. METHODS AND MATERIALS: During lumpectomy, the tumor excision sites of 89 patients were marked by five hemoclips. Postoperative radiographs demonstrated the clips' positions with respect to the extension of the surgical cavity, which was demarcated by air and hematoseroma. Twenty-seven selected patients received interstitial boosts to the tumor bed. The implant was first designed according to the clinical assumptions of the tumor bed's topography and then compared with the radiological findings. Prior to brachytherapy, the planning of the implant's dimension and the needle guidance was performed under simulator control. Dose distributions were first calculated following the Paris System and then electively optimized for the target volume by changing source positions and dwell times. RESULTS: Compared to clinical estimations, the radiological determination of the tumor bed's location revealed an overall potential of topographic errors of 51.8% (14 out of 27 patients), rising up to 78.5% in patients with large adipose breasts (11 out of 13 patients). This observation was due to a high mobility of the tissue, leading to varying tumor site projections at the time of mammography, surgery, and brachytherapy. In all patients, the presimulation of the implant resulted in an adequate coverage of the target volume. In 17 of the 27 treated patients, dose distributions were modified to achieve a higher dose delivery in zones where a higher residual tumor load was expected (boost-in-boost). CONCLUSION: Breast implants have a high potential of geographic misses that can be avoided by intraoperative clip demarcation. The delineation of the tumor bed allows for dose reports actually referring to the target volume and not to the implant system to be obtained. In addition, modern afterloading techniques offer possibilities of individual dose planning with regard to high risk subvolumes within the implanted tissue.

[Can ultrasound detect skeletal metastases?]. / Gelingt sonographisch der Nachweis von Skelettmetastasen?

78 radiologically certified skeletal metastases--osteolytic as well as osteoplastic--were examined via sonography. A defect of the cortex could be seen in 82%, a periostal reaction in 28.2% and a concomitant soft tissue tumorous formation in 79.4%. In proving a soft part component sonography is superior to the conventional x-ray. Our study shows that osseous metastases can be verified by sonography.