Insufficiency fractures in patients treated with pelvic radiotherapy and chemotherapy for uterine and cervical cancer.

Insufficiency fractures are recognised consequences of radiotherapy in gynaecological malignancy with reported incidences between 2.7% and 89%. We aimed to determine the incidence and risk factors for insufficiency fractures in patients receiving radical pelvic radiotherapy for uterine and cervical cancer. A case-note review was undertaken of patients treated between January 2007 and December 2008. Insufficiency fractures were identified from radiographs, computed tomography and magnetic resonance images. Chi-squared and Mann-Whitney tests were performed to determine associations between insufficiency fractures and chemotherapy, steroids and age. A total of 285 patients received pelvic radiotherapy, 137 with uterine and 148 with cervical cancer. Mean age was 59 years. A total of 144 patients received chemotherapy, 101 concurrently and 35 adjuvantly. Bone abnormalities affected 67 patients, 33 had pelvic insufficiency fractures, 12 had multiple fractures and 3 patients developed femoral head avascular necrosis. Use of chemotherapy was not associated with development of fractures (P = 0.949). However, cervical cancer patients had a significantly higher incidence of insufficiency fractures (P = 0.018) and bone pain (P = 0.03) compared with uterine cancer patients. This suggests concurrent chemotherapy may be a significant factor in increasing insufficiency fractures and bone morbidity in these patients and highlights a need for further research to identify, prevent and reduce these long-term complications.

Gastrointestinal symptoms after pelvic radiotherapy: a national survey of gastroenterologists.

PURPOSE: Seventeen thousand patients receive treatment with radical pelvic radiotherapy annually in the UK. Up to 50% develop significant gastrointestinal symptoms. The National Cancer Survivorship Initiative has identified access to specialist medical care for those with complications after cancer as one of their four key needs. We aimed to determine the current practice of British gastroenterologists with regards to chronic gastrointestinal symptoms after pelvic radiotherapy. METHODS: A questionnaire was developed and sent up to a maximum of five times to all UK consultant gastroenterologists. RESULTS: Eight hundred sixty-six gastroenterologists were approached and 165 (20%) responded. Sixty-one percent saw one to four patients annually with bowel symptoms after radiotherapy. Eighteen percent rate the current treatments as effective "often" or "most of the time". Forty-seven percent of gastroenterologists consider themselves "confident with basic cases", with 11% "confident in all cases". Fifty-nine percent thinks a gastroenterologist with a specialist interest should manage these patients. Although only 29% thinks a specific service is required for these patients, 34% rates the current service as inadequate. The ideal service was considered to be gastroenterology-led, multidisciplinary and regional. Low referral rates, poor evidence-base and poor funding are cited as reasons for the current patchy services. CONCLUSIONS: The low response rate contrasts with that from a parallel survey of clinical oncologists. This may reflect the opinion that radiation-induced bowel toxicity is not a significant issue, which may be because only a small proportion of patients are referred to gastroenterologists. The development of new, evidence-based gastroenterology-led services is considered the optimal way to meet the needs of these patients.

SCOTCERV: a phase II trial of docetaxel and gemcitabine as second line chemotherapy in cervical cancer.

OBJECTIVE: The aim of the study was to determine the response rate and response duration of cervical cancer previously treated by cisplatin (with or without radiation) to a combination of docetaxel and gemcitabine. Secondary endpoints were assessment of toxicity and quality of life (QoL) of patients receiving the treatment. METHODS: This was a multicentre phase II trial of 3 weekly docetaxel 75 mg/m(2) day 1 (reduced to 60 mg/m(2) after 32 cycles had been administered) and gemcitabine 1000 mg/m(2) (days 1 and 8). A two stage Gehan design was used initially. Twenty-nine patients recruited had disease outside the irradiated pelvis (Group 1), and 21 had disease confined to the irradiated pelvis (Group 2). The target response for the Gehan 2 design was 25% (Group 1) and 10% (Group 2). RESULTS: The overall response rate for Group 1 was 21.4% (95% CI 8.3-41.0%). Amongst those who had at least 3 cycles of chemotherapy the response rate was 27.3% (95% CI 10.7-50.2%). The median survival was 7.3 months (95% CI 5.4 to 9.2 months) with 39.3% (95% CI 21.7-56.5%) alive at 1 year. In Group 2 the overall response rate was 9.5% (95% CI 1.2%-30.4%). The response rate for those who had at least 3 cycles of chemotherapy was 12.5% (95% CI 1.6-38.4%). The median survival was 7.9 months (95% CI 2.2-13.6 months). Toxicity was mainly haematological with 51% developing grade 3 or 4 neutropenia after at least 1 cycle of chemotherapy. QoL showed a significant deterioration from baseline for physical and role function but there was an improvement in emotional function during treatment. CONCLUSION: Response rates and survival duration were similar to those reported following treatment with platinum based doublets. In view of the relatively poor response rates (no more than 36%) to conventional chemotherapy future developments should be a combination of chemotherapy and biological agents such as VEGFR inhibitors.

Enhancing fraction measured using dynamic contrast-enhanced MRI predicts disease-free survival in patients with carcinoma of the cervix.

BACKGROUND: There is a need for simple imaging parameters capable of predicting therapeutic outcome. METHODS: This retrospective study analysed 50 patients with locally advanced carcinoma of the cervix who underwent dynamic contrast-enhanced MRI before receiving potentially curative radiotherapy. The proportion of enhancing pixels (E(F)) in the whole-tumour volume post-contrast agent injection was calculated and assessed in relation to disease-free survival (DFS). RESULTS: Tumours with high E(F) had a significantly poorer probability of DFS than those with low E(F) (P=0.011). INTERPRETATION: E(F) is a simple imaging biomarker that should be studied further in a multi-centre setting.

The impact of radiotherapy late effects on quality of life in gynaecological cancer patients.

The aims of this study were to assess changes in quality of life (QoL) scores in relation to radical radiotherapy for gynaecological cancer (before and after treatment up to 3 years), and to identify the effect that late treatment effects have on QoL. This was a prospective study involving 225 gynaecological cancer patients. A QoL instrument (European Organisation for the Research and Treatment of Cancer QLQ-C30) and late treatment effect questionnaire (Late Effects Normal Tissues - Subjective Objective Management Analysis) were completed before and after treatment (immediately after radiotherapy, 6 weeks, 12, 24 and 36 months after treatment). Most patients had acute physical symptoms and impaired functioning immediately after treatment. Levels of fatigue and diarrhoea only returned to those at pre-treatment assessment after 6 weeks. Patients with high treatment toxicity scores had lower global QoL scores. In conclusion, treatment with radiotherapy for gynaecological cancer has a negative effect on QoL, most apparent immediately after treatment. Certain late treatment effects have a negative effect on QoL for at least 2 years after radiotherapy. These treatment effects are centred on symptoms relating to the rectum and bowel, for example, diarrhoea, tenesmus and urgency. Future research will identify specific symptoms resulting from late treatment toxicity that have the greatest effect on QoL; therefore allowing effective management plans to be developed to reduce these symptoms and improve QoL in gynaecological cancer patients.

Clinical outcome for chemoradiotherapy in carcinoma of the cervix.

AIMS: Two recent meta-analyses have shown a survival advantage for the addition of concurrent chemotherapy to radiotherapy in the treatment of cervical cancer. However, there is insufficient information available on late toxicity and few data from UK practice. The aims of this study were to examine treatment outcomes (survival and toxicity) in patients with cervical cancer treated with chemoradiation and to compare these with outcomes in patients treated with radiation alone. MATERIALS AND METHODS: Between July 2000 and December 2003, 75 patients with cervical cancer were treated with chemoradiation. Case notes were reviewed retrospectively. Acute and late toxicity were recorded, with late toxicity graded using the Franco-Italian glossary. The median age was 47 years. All patients were staged with examination under anaesthesia and magnetic resonance imaging scans. Forty-two patients were treated with concurrent chemoradiation alone and 33 patients were treated with a combination of neoadjuvant and concurrent chemoradiation. This was due to waiting list problems. The chemotherapy used was cisplatin 40 mg/m(2) weekly with radiotherapy, (the neoadjuvant dose was 60 mg/m(2) 3 weekly). External beam radiotherapy was given to the pelvis (40-45 Gy/20 fractions/4 weeks) followed by low dose rate brachytherapy (22.5-32.5 Gy to point A). Patients who were unable to have brachytherapy were given an external beam boost (15-20 Gy/8-10 fractions). RESULTS: The 3-year overall survival rate was 70%, with an estimated 5-year overall survival rate of 60%. The 3-year disease-free survival was 63.6%, with an estimated 5-year disease-free survival rate of 55%. Compared with the cohort of 183 patients from the Christie Hospital in a 1993 audit, there was a trend towards improved overall survival from 49 to 60% (P=0.06), which may become significant with longer follow-up. There were seven patients (9.3%) with grade 3 toxicity and no cases of grade 4 toxicity. In comparison with patients treated in the 1993 audit, the late toxicity rate has increased from 3.4 to 9.3%, but this was not statistically significant (P=0.14). CONCLUSION: There was a trend towards improved survival with concurrent chemoradiation in this cohort of patients that may become significant with longer follow-up.

Estimation of renal function -- what is appropriate in cancer patients?

AIMS: To compare the accuracy of renal assessment in patients with cancer using radioisotope glomerular filtration rate (GFR), urine collection for creatinine clearance, Cockroft-Gault, Modification of Diet in Renal Disease (MDRD) and Wright formulae. MATERIALS AND METHODS: Measurements of isotope GFR from 367 patients were compared with estimates from the described methods (Cockroft-Gault, MDRD, Wright). An analysis including a further 252 patients with an isotope GFR < or = 50 ml/min was also carried out. RESULTS: The Wright formula was the most accurate form of estimating renal function for the first study group. The formulae were similar in accuracy in the second study group. CONCLUSIONS: The Wright formula is the most accurate form of estimation of renal function in comparison with the isotope GFR for cancer patients. When there is a large proportion of patients with a low isotope GFR (< or = 50 ml/min), the formulae have similar accuracy.

Does the Use of Volumetric Modulated Arc Therapy Reduce Gastrointestinal Symptoms after Pelvic Radiotherapy?

AIMS: Growing numbers of patients with cancer are surviving after treatment with pelvic radiotherapy. We evaluated the technique of volumetric modulated arc therapy (VMAT), which delivers a decreased dose to the organs at risk. We aimed to determine outcomes of this technique in terms of patient-reported acute toxicity and late effects and correlate the frequency of gastrointestinal symptoms with the volume of bowel receiving radiation dose. MATERIALS AND METHODS: Patients who were to receive VMAT for gynaecological malignancy completed patient-reported outcomes at baseline, the end of treatment, 8 weeks and 1 year. The rates of patient-reported toxicity were correlated with the volume of bowel irradiated. RESULTS: The frequencies of patient-reported gastrointestinal symptoms increased in the acute toxicity phase and tended to improve at 1 year, with the exception of faecal incontinence and rectal bleeding (P < 0.05). There was not a strong association between the volume of small bowel that was irradiated (P > 0.05 at all dose levels) and reported toxicity, suggesting that other factors are involved in the development of toxicity. CONCLUSION: Although VMAT decreases the dose delivered to the small bowel, this does not translate into a reduction in patient-reported toxicity.

Salvaging locoregional recurrence with radiotherapy after surgery in early cervical cancer.

AIMS: To determine the outcome and morbidity after radiotherapy for locally recurrent cervical cancer. MATERIALS AND METHODS: Women who presented with locally recurrent cervical cancer after surgery alone during 1985 and 1997 were identified from the hospital database. Data were collected and analysed to include the stage at first diagnosis, staging investigations before surgery, the surgical procedure, the indication for radiotherapy, the type of radiotherapy, morbidity and survival. RESULTS: In total, 130 women had radical external beam radiotherapy and/or intracavitary brachytherapy for locoregional recurrence during the defined study period. The 5-year disease-specific survival for the study population was 40.2%. Women who were treated for vault recurrence had a significantly better 5-year disease-free survival compared with women who developed nodal recurrence alone (55.4% vs 12.5%). This group of women also had a significantly slower rate of disease progression after radiotherapy than women with nodal recurrence (48.7% vs 87.5%, P=0.0001). CONCLUSION: Radical radiotherapy alone is able to salvage 55% of vaginal vault recurrences after surgery for cervical cancer with minimal late toxicity. Salvage rates in women with pelvic nodal recurrences are considerably lower. Chemoradiotherapy using intensity-modulated radiotherapy to deliver an escalated radiotherapy dose needs to be pursued to improve locoregional control.

Carbonic anhydrase (CA IX) expression, a potential new intrinsic marker of hypoxia: correlations with tumor oxygen measurements and prognosis in locally advanced carcinoma of the cervix.

There is increasing evidence that hypoxia-regulated gene expression influences tumor aggressiveness, contributing to the poorer outcome of patients with hypoxic tumors. The role of the transcriptional complex hypoxia-inducible factor-1 as an important mediator of hypoxia-regulated gene expression is one of the best documented pathways. Recently, it has emerged that certain tumor-associated carbonic anhydrases (CAs) can be added to the list of known hypoxia-inducible factor-responsive genes. Here we show that the immunohistochemical expression of the tumor-associated CA IX is correlated with the level of hypoxia in human cervical tumors. We performed a prospective study in 68 patients where needle electrodes were used to make direct measurements of tumor oxygenation levels. CA IX expression was evaluated immunohistochemically in pretreatment tumor biopsies. There was a significant positive correlation between the level of tumor hypoxia (HP5) and the extent of CA IX expression. A retrospective study of 130 squamous cell cervical carcinomas demonstrated that a semiquantitative immunohistochemical analysis of CA IX expression in tumor biopsies is a significant and independent prognostic indicator of overall survival and metastasis-free survival after radiation therapy. These studies provide clinical evidence that CA IX expression is up-regulated in hypoxic human cervical tumors and is associated with a poor prognosis. CA IX may act as an intrinsic marker of tumor hypoxia and poor outcome after radiation therapy. The level of CA IX expression may be used to aid in the selection of patients who would benefit most from hypoxia-modification therapies or bio-reductive drugs.

High tumor angiogenesis is associated with poorer survival in carcinoma of the cervix treated with radiotherapy.

The purpose of this study was to examine the relationship between tumor angiogenesis and prognosis in carcinoma of the cervix treated with radiotherapy with a median follow-up time of 55 months. A retrospective study was carried out on 111 patients. Formalin-fixed, paraffin-embedded tumor biopsies were stained with anti-factor VIII using immunohistochemistry. Tumor angiogenesis was assessed by scoring the distance to the closest microvessel from random points within the tumor and the intratumor microvessel density (IMD) in the areas of highest neovascularization. High vascularity, as measured by both methods, was associated with a poor prognosis but was only significant for IMD. The 5-year survival rates for tumors with high versus low values were 50 and 65%, respectively. IMD was a significant prognostic factor within a Cox multivariate analysis. Higher tumor vascularity was associated with lower overall survival and locoregional control, but this association was not significant in the case of metastasis-free survival. The method used to assess tumor vascularity is important. The level of angiogenesis in carcinoma of the cervix is an independent prognostic parameter.

The Scottish and Manchester randomised trial of neo-adjuvant chemotherapy for advanced cervical cancer.

204 eligible patients were entered into a multicentre randomised trial of neo-adjuvant chemotherapy prior to radical radiotherapy. The aim of this study was to assess whether there was any survival advantage in patients undergoing chemotherapy and radiotherapy compared with those given radiotherapy alone. Patients were aged up to 70 years, performance status 0-1/2, with bulky stage IIb, stage III or stage IVa squamous or adenosquamous carcinoma. Three cycles of methotrexate 100 mg/m2 and cisplatin 50 mg/m2 were given at 2-weekly intervals before radical radiotherapy. 104 eligible patients received the combination treatment and 100 radiotherapy only. The two arms of the study were well balanced for tumour and patient characteristics. The response rate to chemotherapy was 49%, 33% of patients in the radiotherapy (XRT) alone arm and 45% of the combination arm were clinically free of tumour at the end of treatment. The median follow-up for surviving patients is 5.4 years (range: 11 months-8 years) and 84% have been followed-up for more than 4 years. 134 patients have died (68 XRT only, 66 combined arm). The median survival RT alone was 111 weeks (95% confidence interval (CI) 72-151 weeks), combination arm 125 weeks (95% CI 79-170 weeks). The estimated death ratio is 0.79 (P = 0.19, 95% CI 0.56-1.12). The estimated 3-year survival is 40% (95% CI 30-50%) RT only compared with 47% (95% CI 37-57%) in the combination arm. Acute and late toxicity of radiotherapy was not increased by the addition of chemotherapy.

Pretreatment plasma TGF beta 1 levels are prognostic for survival but not morbidity following radiation therapy of carcinoma of the cervix.

PURPOSE: To determine whether pretreatment plasma-transforming growth factor beta 1 (TGF beta 1) levels are prognostic for tumor control and late morbidity following radiation therapy in carcinoma of the cervix. METHODS AND MATERIALS: The study was comprised of 79 patients undergoing radiotherapy with curative intent for Stage I-III carcinoma of the cervix. TGF beta 1 levels were analyzed using ELISA. Late morbidity was measured using the Franco-Italian glossary. Data were available for the pretreatment levels of circulating tumor markers that represent disease burden, and for peripheral blood lymphocyte radiosensitivity measured as SF2. RESULTS: Pretreatment TGF beta 1 levels were a significant prognostic factor for survival and local control. There were weak significant correlations of TGF beta 1 levels with disease stage and the levels of circulating tumor markers (CA125, TPA). There was a weak significant correlation between TGF beta 1 levels and normal cell radiosensitivity (lymphocyte SF2). There was no relationship between TGF beta 1 levels and grade of morbidity and pretreatment TGF beta 1 levels were not a significant prognostic factor for the probability of developing late morbidity. CONCLUSION: In carcinoma of the cervix, pretreatment TGF beta 1 levels reflect tumor burden and are a significant prognostic factor for survival. Despite an underlying weak relationship of TGF beta 1 levels with intrinsic normal cell radiosensitivity, pretreatment levels are not prognostic for the probability of developing late complications. This finding does not rule out the possible usefulness of measurements toward the end of treatment once tumor burden has been reduced.

The intrinsic radiosensitivity of cervical carcinoma: correlations with clinical data.

PURPOSE: The aims of the work were to study the intrinsic radiosensitivity of tumor biopsies from patients with cervical carcinoma and to correlate the data with information on patient age, disease stage, differentiation status, tumor volume, and tumor ploidy. METHODS AND MATERIALS: Radiosensitivity was assessed for 145 tumors in vitro as surviving fraction at 2 Gy (SF2) using a clonogenic assay. RESULTS: Although the clonogens in tumors classified as Stage I or II tended to be more radiosensitive than in Stage III or IV disease, the difference was not statistically significant (p > 0.15). There was also no significant difference in the intrinsic radiosensitivity of well, moderately, or poorly differentiated tumors or between squamous cell carcinoma and adenocarcinoma (p > 0.53). There was no correlation between patient age and tumor radiosensitivity (p = 0.49). Large volume (> or = 4 cm) disease was more radioresistant than small volume (< 4 cm) disease, but the difference was not significant (p = 0.08). Finally, diploid tumors tended to be more radioresistant than aneuploid tumors (p = 0.07). CONCLUSION: The intrinsic radiosensitivity of cervix tumors is independent of disease stage, tumor grade, and patient age. Weak trends, however, were observed of increased tumor radioresistance for large volume disease and diploid tumors, suggesting that tumor SF2 may not be a completely independent parameter.

Incorporating biologic measurements (SF(2), CFE) into a tumor control probability model increases their prognostic significance: a study in cervical carcinoma treated with radiation therapy.

PURPOSE: To assess whether incorporation of measurements of surviving fraction at 2 Gy (SF(2)) and colony-forming efficiency (CFE) into a tumor control probability (tcp) model increases their prognostic significance. METHODS AND MATERIALS: Measurements of SF(2) and CFE were available from a study on carcinoma of the cervix treated with radiation alone. These measurements, as well as tumor volume, dose, and treatment time, were incorporated into a Poisson tcp model (tcp(alpha,rho)). Regression analysis was performed to assess the prognostic power of tcp(alpha,rho) vs. the use of either tcp models with biologic parameters fixed to best-fit estimates (but incorporating individual dose, volume, and treatment time) or the use of SF(2) and CFE measurements alone. RESULTS: In a univariate regression analysis of 44 patients, tcp(alpha,rho) was a better prognostic factor for both local control and survival (p < 0.001 and p = 0.049, respectively) than SF(2) alone (p = 0.009 for local control, p = 0.29 for survival) or CFE alone (p = 0.015 for local control, p = 0.38 for survival). In multivariate analysis, tcp(alpha,rho) emerged as the most important prognostic factor for local control (p < 0.001, relative risk of 2.81). After allowing for tcp(alpha,rho), CFE was still a significant independent prognostic factor for local control, whereas SF(2) was not. The sensitivities of tcp(alpha,rho) and SF(2) as predictive tests for local control were 87% and 65%, respectively. Specificities were 70% and 77%, respectively. CONCLUSIONS: A Poisson tcp model incorporating individual SF(2), CFE, dose, tumor volume, and treatment time was found to be the best independent prognostic factor for local control and survival in cervical carcinoma patients.

Changes in oxygenation during radiotherapy in carcinoma of the cervix.

PURPOSE: The aim of this study was to investigate changes in tumor oxygenation, assessed by polarographic needle electrode measurements, following fractionated external beam radiotherapy in carcinoma of the cervix. METHODS AND MATERIALS: Normal and tumor tissue oxygenation was measured in 19 patients prior to radiotherapy and after 40-45 Gy of external beam radiotherapy delivered in 20 fractions over 4 weeks. All measurements were performed during anesthesia. RESULTS: There was no significant difference in the level of normal tissue oxygenation pre- and post radiotherapy. The individual patient median tumor pO2 values ranged from 0 to 31 mmHg pre-radiotherapy and 1 to 61 mmHg post-radiotherapy. The mean of the 19 median pO2 values increased from 8 (SD +/- 10) mmHg to 20 (+/- 20) mmHg following external beam radiotherapy. The increase was significant by paired Wilcoxon test (p = 0.011). There was also a significant fall in the proportion of values < 5 mmHg (p = 0.040). Although this value remained constant, or fell, in the majority of patients (15/19), it increased in 4 tumors. Tumor size pre- and postradiotherapy did not correlate with the level of pretreatment oxygenation; neither did the change in tumor size and change in level of oxygenation. CONCLUSION: The level of tumor oxygenation increased in the majority of patients (15/19) following 40-45 Gy of radiotherapy in carcinoma of the cervix.

Lymphocyte radiosensitivity is a significant prognostic factor for morbidity in carcinoma of the cervix.

PURPOSE: To study the relationship between pretreatment peripheral blood lymphocyte radiosensitivity and morbidity following radiation therapy. METHODS AND MATERIALS: A prospective study was carried out in which patients with carcinoma of the cervix underwent radiation therapy. Intrinsic radiosensitivity was measured on pretreatment peripheral blood lymphocytes, using a limiting dilution clonogenic assay. Late morbidity was assessed using the Franco-Italian glossary. Results were correlated in an actuarial analysis. RESULTS: There were no correlations between the measured lymphocyte radiosensitivity (SF2) and colony-forming efficiency, patient age, tumor grade, or disease stage. For 83 patients, lymphocyte SF2 was a significant prognostic factor for the probability of developing both any (p = 0.002) and Grade 3 (p = 0.026) morbidity. In 174 patients, stage showed borderline significance as a prognostic factor for morbidity (p = 0.056). However, the type of treatment (intracavitary alone, intracavitary plus parametrial irradiation, single insertion plus whole-pelvis irradiation) was significantly associated with the probability of developing late complications (p = 0.013). There was a weak significant inverse correlation between lymphocyte SF2 and grade of morbidity (r = -0.34, p = 0.002). CONCLUSION: These data highlight the importance of normal cell radiosensitivity as a factor determining radiation therapy response. They also show that peripheral blood lymphocyte SF2 is a highly significant prognostic factor for the probability of developing late radiation morbidity, and that carcinoma of the cervix is a good model for testing radiobiologic principles in the clinic.

Invasive oxygen measurements and pimonidazole labeling in human cervix carcinoma.

PURPOSE: This study was designed to compare tumor hypoxia assessed by invasive O2 sensitive electrodes and pimonidazole labeling in primary human cervix carcinomas. METHODS AND MATERIALS: Twenty-eight patients with primary cervix carcinomas (FIGO Stage Ib-IVa) were investigated. Both invasive pO2 measurements and pimonidazole labeling were obtained in all patients. Before treatment, patients were given pimonidazole as a single injection (0.5 g/m2 i.v.). Ten to 24 h later, oxygenation measurements were done by Eppendorf histography, and after this procedure biopsies were taken for pimonidazole-binding analysis. Tumor oxygen partial pressure (pO2) was evaluated as the median tumor pO2 and the fraction of pO2 values < or = 10 mmHg (HF10). Biopsies were formalin fixed and paraffin embedded, and hypoxia was detected by immunohistochemistry using monoclonal antibodies directed against reductively activated pimonidazole. Pimonidazole binding was evaluated by a semiquantitative scoring system. RESULTS: Both Eppendorf measurements and pimonidazole binding showed large intra-and intertumor variability. A comparison between pimonidazole binding expressed as the fraction of fields at the highest score and HF10 showed a trend for the most well-oxygenated tumors having a low fraction of fields; however, the correlation did not reach statistical significance (p = 0.43, r = 0.165; Spearman's rank correlation test). CONCLUSION: Hypoxia measured in human uterine cervix carcinomas is heterogeneously expressed both within and between tumors when assessed by either invasive pO2 measurements or pimonidazole binding. Despite a trend that tumors with high pO2 values expressed less pimonidazole binding, no correlation was seen between the two assays in this preliminary report.

A correlation between residual DNA double-strand breaks and clonogenic measurements of radiosensitivity in fibroblasts from preradiotherapy cervix cancer patients.

PURPOSE: To study the relationship between residual DNA damage and clonogenic measurements of radiosensitivity in fibroblasts from pretreatment cervix cancer patients. METHODS AND MATERIALS: Early passage vaginal fibroblasts from nine preradiotherapy cervix cancer patients and two radiosensitive skin fibroblast cell strains were studied. Cell survival was measured by clonogenic assay following both high and low dose rate irradiation. Residual DNA damage was measured using pulsed-field gel electrophoresis (PFGE) after irradiating radiolabeled, plateau-phase cells at 37 degrees C and allowing 24 h for repair. DNA damage was expressed both in terms of the residual damage slope (fitted to data from 60 to 150 Gy) and the fraction of activity released (FAR) following 150 Gy. RESULTS: The surviving fraction at 2 Gy (SF2) values after high dose rate irradiation for the vaginal fibroblasts ranged from 0.15 to 0.32 (a 2.2-fold difference). When the two radiosensitive cell strains were included, residual damage, expressed as the residual damage slope, correlated with alpha (r = 0.82, p = 0.002), D bar (r = -0.91, p < 0.001) and SF2 (p = -0.79, p = 0.004), and when the vaginal fibroblasts alone were studied, the residual damage slope again correlated with clonogenic survival, although less strongly [alpha (r = 0.66, p = 0.053), D bar (r = -0.83, p = 0.006), and SF2 (r = -0.63, p = 0.07)]. Within the group of vaginal fibroblasts there was a 4.0-fold difference in residual DNA damage slope. When residual damage was expressed as FAR at 150 Gy, then for all cell strains the correlations were alpha: r = 0.78, p = 0.004, D bar: r = -0.86, p = 0.001, and SF2: r = -0.78, p = 0.004, and for the vaginal fibroblast strains alone the correlations were alpha: r = 0.60, p = 0.088, D bar: r = -0.75, p = 0.02, and SF2: r = 0.62, p = 0.077. CONCLUSION: This study confirms previous findings that residual DNA damage correlates with clonogenic survival in fibroblasts. In addition, it demonstrates a correlation for fibroblasts from pretreatment cervix cancer patients demonstrating a relatively small range of SF2 values.

Radiosensitivity testing of primary cervical carcinoma: evaluation of intra- and inter-tumour heterogeneity.

Biopsies from 89 patients with cervical carcinoma were studied using a clonogenic assay to obtain values for the surviving fraction at 2 Gy (SF2). Heterogeneity in intrinsic radiosensitivity was investigated by independently processing multiple biopsies from 18 tumors. No significant differences between intra-tumour SF2 values were demonstrated (p = 0.30). The results have shown that intra-tumour heterogeneity is not a limitation to radiosensitivity testing using the Courtenay-Mills assay. A wide range of values (0.13-0.97) for SF2 was obtained with a mean value of 0.47 +/- 0.18 (+/- 1 S.D., CV = 38%) for 52 squamous cell carcinomas and 0.59 +/- 0.27 for four adenocarcinomas. There were statistically significant differences between the individual tumours (p less than 0.001). From the analysis-of-variance of all the SF2 results it appears to be the surviving fractions below about 0.40 and those above about 0.7 which show significant differences in radiosensitivity between pairs of tumours (p = 0.05). Also 36% of the values of SF2 show significant differences from the mean SF2 of all tumours. The storage of tumour cell suspensions in liquid nitrogen improved the colony-forming efficiency (CFE) but it did not alter the radiosensitivity.