4 Porównanie histogramów objętościowych odbytnicy i ściany odbytnicy u chorych na raka szyjki macicy otrzymujących dojamową brachyterapię

Celem pracy było oszacowanie dawki, jaką otrzymuje odbytnica jako organ krytyczny podczas dojamowego napromieniania chorych na raka szyjki macicy, na podstawie DVH (Dose Volume Histogram – histogram dawki w całej objętości odbytnicy) i DWH (Dose Wall Histogram – histogram dawki w ścianie odbytnicy).Zgodnie z Raportem ICRU nr 38 dawka w organach krytycznych, podczas napromieniania chorych na raka szyjki macicy określana jest na podstawie punktów. Ponieważ, niezakontrastowana odbytnica nie jest widoczna na zdjęciach rtg, punkty, w których mierzona jest dawka wyznaczane są względem aplikatorów. W związku z tym rzeczywisty rozkład dawki jaką otrzymuje odbytnica jest nieznany. Stosując trójwymiarowy system do planowania leczenia i zdjęcia TK można przeanalizować rozkład dawki w wybranych narządach.Naszym materiałem były zdjęcia TK oraz komputerowe plany leczenia dla 10 losowo wybranych pacjentek leczonych z powodu raka szyjki macicy. Na zdjęciach TK nie jest widoczna ściana. odbytnicy, dlatego do obliczania DWH wykorzystaliśmy istniejące kontury zewnętrzne odbytnicy oraz wygenerowane na podstawie matematycznego modelu tego narządu jego kontury wewnętrzne. Po przeanalizowaniu histogramów DVH i rożnych histogramów DWH w zależności od grubości ściany odbytnicy stwierdziliśmy, że dla potrzeb codziennej praktyki klinicznej lepiej jest oprzeć się na dawce z DVH w objętości 2 cm3 niż 5 cm3 jako parametru do oceny powikłań w postaci przetoki pochwowo-odbytniczej. Objętość 2 cm3 z DWH jest bliższe wartości dawki dla 2 cm3 z DVH niż analogiczne wartości dla objętości 5 cm3. W tym celu obliczono DVH i DWH, a następnie odczytano dawki dla objętości 2 i 5 cm3. Do policzenia histogramów wykorzystano kontury narządu na zdjęciach TK oraz program generujący wewnętrzną ścianę odbytnicy

Ewing's sarcoma of the pelvis: changes over 25 years in treatment and results

The pelvic localisations of Ewing's sarcoma have the worst prognosis due to large size at diagnosis, frequent distant metastases, radiosensitive organs next to the tumour and difficult surgery. The purpose of the present study was to analyse treatment results over a period of 25 years and to investigate the impact of newer chemotherapy schedules, improved radiotherapy techniques and newer surgical methods on the prognosis. 35 children and young adults were identified from 1967 to 1994 for whom diagnosis, presentation, performed treatment and outcome were available. Tumour size, as measured from CT scans, response to chemotherapy and radiotherapy target volume, could be reviewed in the later years. Actuarial 5-year survival for the whole group was 31% and for the 24 non-metastatic patients 40%, with a disease-free interval of 19%. Tumour size could be measured in 27 patients and ranged from 36 to 1540 cm3. There were 12 local recurrences, 1 in the 4 patients treated with surgery. After 1983, 9 out of 17 irradiated patients developed local failure. 3 patients had adequate fields and one a close field which did not cover completely the prechemotherapy extent and 3 of these recurred. All 4 patients with stable disease after neoadjuvant CT failed locally, not withstanding high-dose radiotherapy. The mean length of neoadjuvant CT tended to be shorter in patients without local relapse. There was no significant difference in survival before and after 198

Ewing’s sarcoma of the pelvis: changes over 25 years in treatment and results

The pelvic localisations of Ewing's sarcoma have the worst prognosis due to large size at diagnosis, frequent distant metastases, radiosensitive organs next to the tumour and difficult surgery. The purpose of the present study was to analyse treatment results over a period of 25 years and to investigate the impact of newer chemotherapy schedules, improved radiotherapy techniques and newer surgical methods on the prognosis. 35 children and young adults were identified from 1967 to 1994 for whom diagnosis, presentation, performed treatment and outcome were available. Tumour size, as measured from CT scans, response to chemotherapy and radiotherapy target volume, could be reviewed in the later years. Actuarial 5-year survival for the whole group was 31% and for the 24 non-metastatic patients 40%, with a disease-free interval of 19%. Tumour size could be measured in 27 patients and ranged from 36 to 1540 cm3. There were 12 local recurrences, 1 in the 4 patients treated with surgery. After 1983, 9 out of 17 irradiated patients developed local failure. 3 patients had adequate fields and one a close field which did not cover completely the prechemotherapy extent and 3 of these recurred. All 4 patients with stable disease after neoadjuvant CT failed locally, not withstanding high-dose radiotherapy. The mean length of neoadjuvant CT tended to be shorter in patients without local relapse. There was no significant difference in survival before and after 198

Vaginal brachytherapy versus pelvic external beam radiotherapy for patients with endometrial cancer of high-intermediate risk (PORTEC-2): an open-label, non-inferiority, randomised trial

Background After surgery for intermediate-risk endometrial carcinoma, the vagina is the most frequent site of recurrence. This study established whether vaginal brachytherapy (VBT) is as effective as pelvic external beam radiotherapy (EBRT) in prevention of vaginal recurrence, with fewer adverse effects and improved quality of life. Methods In this open-label, non-inferiority, randomised trial undertaken in 19 Dutch radiation oncology centres, 427 patients with stage I or IIA endometrial carcinoma with features of high-intermediate risk were randomly assigned by a computer-generated, biased coin minimisation procedure to pelvic EBRT (46 Gy in 23 fractions; n=214) or VBT (21 Gy high-dose rate in three fractions, or 30 Gy low-dose rate; n=213). All investigators were masked to the assignment of treatment group. The primary endpoint was vaginal recurrence. The predefined non-inferiority margin was an absolute difference of 6% in vaginal recurrence. Analysis was by intention to treat, with competing risk methods. The study is registered, number ISRCTN16228756. Findings At median follow-up of 45 months (range 18-78), three vaginal recurrences had been diagnosed after VBT and four after EBRT. Estimated 5-year rates of vaginal recurrence were 1.8% (95% CI 0.6-5.9) for VBT and 1.6% (0.5-4-9) for EBRT (hazard ratio [HR] 0.78, 95% CI 0-17-3.49; p=0.74). 5-year rates of locoregional relapse (vaginal or pelvic recurrence, or both) were 5.1% (2.8-9.6) for VBT and 2.1% (0.8-5.8) for EBRT (HR 2.08,0.71-6.09; p=0.17). 1.5% (0.5-4.5) versus 0.5% (0.1-3.4) of patients presented with isolated pelvic recurrence (HR 3.10, 0.32-29.9; p=0.30), and rates of distant metastases were similar (8.3% [5.1-13.4] vs 5.7% [3.3-9.9]; HR 1.32, 0.63-2.74; p=0.46). We recorded no differences in overall (84-8% [95% CI 79.3-90.3] vs 79.6% [71.2-88.0]; HR 1.17, 0.69-1.98; p=0.57) or disease-free survival (82.7% [76.9-88.6] vs 78.1% [69.7-86.5]; HR 1.09, 0.66-1.78; p=0.74). Rates of acute grade 1-2 gastrointestinal toxicity were significantly lower in the VBT group than in the EBRT group at completion of radiotherapy (12.6% [27/215] vs 53.8% [112/208]). Interpretation VBT is effective in ensuring vaginal control, with fewer gastrointestinal toxic effects than with EBRT. VBT should be the adjuvant treatment of choice for patients with endometrial carcinoma of high-intermediate risk.Immunology and molecular genetics of gynecological cancersBiological, physical and clinical aspects of cancer treatment with ionising radiationClinical OncologyTI9 - Endometriumpathologi