Radical Radiotherapy For Cervical Cancer Research Articles

Interfractional variation in position of the uterus during radical radiotherapy for cervical cancer

Background and purpose This study was conducted to investigate the positional change of the uterus during radiotherapy which can degrade the accuracy of three-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT). Patients and methods Sixty-six patients received radical radiotherapy for cervical cancer in Samsung Medical Center. For each patient, two MRI scans were taken; one was before beginning radiotherapy and the other was in the third or fourth week of radiotherapy. In T2-weighted MRI images, the positional change of the uterus was quantified by measuring six parameters; the distance from the external uterine opening to the isthmus of the uterus (Dcx), the distance from the isthmus of the uterus to the uterine fundus (Dco), the perpendicular distance of the uterine body to the uterine corpus (Dco-per), the angle between the vertical line and the cervical canal in sagittal images (Acx), the uterine corpus angle from the vertical line in sagittal plan (Aco), the angle between the uterine corpus from an arbitrary bony landmark and a vertical mid line in axial images (Aco-axi) Results Mean value of change in Dcx+Dco of tumor size during treatment was 8.0 mm in small tumors and 17.9 mm in large tumors. Among 44 anteflexed uterus patients, 5 changed into a retroflexed position. 12 patients (18%) had a greater than 30° variation in any angle. For patients under 60 years, the difference in Acx was statistically significant. Conclusions Positional changes of the uterus during radiotherapy should be considered in the treatment planning of 3DCRT or IMRT, particularly in patients under 60 years or those with tumor size greater than 4 cm in diameter.

A phase III randomized study of misonidazole plus radiation vs. radiation alone for cervix cancer

Background and purpose A randomized-controlled study of radical radiotherapy for cervical cancer with or without the hypoxic sensitizer, misonidazole was conducted from 1981 to 1984 to investigate its therapeutic benefit. Patients and methods Seventy-three patients were accrued from the Princess Margaret Hospital, and St John Regional Cancer Centre and randomized to either misonidazole (MISO, n=39) or placebo (P, n=34) in addition to radiotherapy. MISO was given orally each day 4 h prior to external beam radiation treatment (45 Gy to midplane in 20 daily fractions) at a dose of 0.45 g/m 2, as well as during intra-uterine brachytherapy (40 Gy). Results The 10-year overall survival (OS) for the entire group was 46%, and the disease-free survival (DFS) was 39%. The 10-year OS for patients in the MISO arm was 45%, compared to 49% for the P arm ( P=0.89). The corresponding DFS figures were 36 and 43%, respectively, ( P=0.6). Ten patients (14%) developed severe late complications (grade 3 or 4). The 10-year serious late complication rate was 14% for MISO and 12% for P ( P=0.51). Conclusions Misonidazole failed to improve the outcome of patients with cervix cancer treated with radiotherapy.

Interfractional variation in position and volume of the uterus during radical radiotherapy for cervical cancer

Purpose/Objective: Recently, intensity-modulated radiotherapy (IMRT) has been applied to gynecological malignacies. Several studies reported that 3-dimensional conformal (3DCRT) and IMRT in the treatment of gynecological malignancies was superior to conventional whole pelvis irradiation in dose conformity to PTV and in reducing the irradiated volume of normal tissues. This study was conducted to investigate the positional change of uterus during radiotherapy, which can degrade the accuracy of 3DCRT and IMRT.

Impact of multiple HPV infection on response to treatment and survival in patients receiving radical radiotherapy for cervical cancer.

To obtain information on the incidence and the clinical significance of infection with various types of the human papillomavirus (HPV) in cancer of the uterine cervix, we retrospectively examined the HPV status of 106 patients who had received radical radiotherapy for cervical cancer stages IB to IIIB. DNA was extracted from formalin-fixed, paraffin-embedded biopsies and PCR was carried out to identify HPV types 16, 18, 31, 35, 33 and 45. To detect additional HPV types, consensus PCR products were cloned and sequenced. A catalyzed signal-amplified colorimetric in situ hybridization was carried out in 84 of 106 specimens as a positive control. Response to therapy, progression-free survival (PFS) and cervical cancer-specific survival (CCSS) were the statistical endpoints. Survival analysis was carried out using univariate and multivariate analysis (Cox regression). Ninety-six patients (90.6%) were HPV-positive and 42/96 (43.7%) were positive for multiple HPV types. Eight patients had persistent disease after radiotherapy. From these 8 patients, 7 were infected with multiple HPV types and only 1 patient had an infection with a single HPV type. After a median follow up period of 50 months, patients with multiple HPV infection had a significantly shorter PFS and CCSS compared to those with single HPV infection (24.8% and 34.9% vs. 64% and 60.8%, Log rank, p < 0.01 and 0.04). In multivariate analysis, the presence of multiple HPV types (RR 1.9), node status (RR 2.3), tumor size (RR 3.2) and histologic type (RR 4.8) were independent prognostic factors of CCSS. Our results demonstrate that the presence of multiple HPV types is associated with poor response and with reduced survival in cervical cancer patients who receive radiotherapy as the primary treatment.

The effect of overall treatment time on the survival and toxicity of radical radiotherapy for cervical carcinoma

Background and purpose: Overall treatment time is an important factor in the outcome of radical radiotherapy in head and neck, bladder and lung cancer and in cervix cancer treated over more than 7 weeks. This study analysed the effect of prolongation of overall treatment time on survival and late morbidity for patients receiving radical radiotherapy for cervical cancer treated with a 4-week regimen. Materials and methods: Using the departmental SAS data-base we identified all patients with cervix cancer treated between 1974 and 1988 and investigated the 647 patients who received 20 fractions of external beam radiotherapy plus intracavitary therapy with a total dose to point A of at least 60 Gy. A retrospective case-note review identified tumour and treatment-related variables. Results: Four hundred and twenty-five (66%) patients had at least one gap in treatment. Seventy-nine gaps (11%) were due to unavoidable patient or treatment-related causes. We could not find an effect of a treatment gap ( P=0.43) or an increased overall treatment time ( P=0.79) on the cause specific survival of patients. There was significantly more grade 4 morbidity in those patients treated over a short period (29–32 days) compared to the rest ( P=0.005), possibly related to the loss of radiotherapy-free days to weekend intracavitary insertions. Conclusions: We could not demonstrate a significant effect of overall treatment time in this series of patients, almost all of whom were treated in less than 7 weeks. Those patients treated over the shortest period had an increased incidence of late morbidity.