Biomedical subjects

Michael Milosevic

Publications and source records attributed to Michael Milosevic.

At least 19 recordsLinked to original sources

PubMed2007

Correlations between dynamic contrast-enhanced magnetic resonance imaging-derived measures of tumor microvasculature and interstitial fluid pressure in patients with cervical cancer.

PURPOSE: To correlate permeability (rk(trans)), extracellular volume fraction (rv(e)), relative to muscle and initial area under the enhancement curve (IAUC(60m)) determined by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with in vivo measurements of interstitial fluid pressure (IFP) in patients with cervical cancer. MATERIALS AND METHODS: DCE-MRI and IFP measurements were performed of cervical tumors of 32 patients prior to therapy. Median tumor rk(trans) and rv(e) were derived from a bidirectional two-compartment model using an input function derived from muscle. Median IAUC(60m) was defined as the integral of tumor enhancement in the first 60 seconds divided by the similar muscle enhancement integral. These parameters were correlated with the mean tumor IFP. RESULTS: There was a significant negative correlation between IAUC(60m) and IFP (r = -0.42, P = 0.016) and between rk(trans) and IFP (r = -0.47, P = 0.008). The was no significant correlation between IFP and rv(e). CONCLUSION: There is a moderate negative correlation between IAUC(60m), rk(trans), and IFP in cervical cancer. This suggests that these parameters may be of value in assessment of tumor behavior.

Adult↗

PubMed2006

A prospective phase I-II trial of the cyclooxygenase-2 inhibitor celecoxib in patients with carcinoma of the cervix with biomarker assessment of the tumor microenvironment.

PURPOSE: To evaluate the toxicity and effectiveness of celecoxib in combination with definitive chemoradiotherapy (CRT) in women with locally advanced cervical cancer. METHODS AND MATERIALS: Thirty-one patients were accrued to a phase I-II trial of celecoxib 400 mg by mouth twice per day for 2 weeks before and during CRT. Tumor oxygenation (HP(5)) and interstitial fluid pressure (IFP) were measured before and 2 weeks after celecoxib administration alone. The median follow-up time was 2.7 years (range, 1.1-4.4 years). RESULTS: The most common acute G3/4 toxicities were hematologic (4/31, 12.9%) and gastrointestinal (5/31, 16.1%) largely attributed to chemotherapy. Late G3/4 toxicity was seen in 4 of 31 patients (13.7% actuarial risk at 2 yr), including fistulas in 3 patients (9.7%). Within the first year of follow-up, 25 of 31 patients (81%) achieved complete response (CR), of whom 20 remained in CR at last follow-up. After 2 weeks of celecoxib administration before CRT, the median IFP decreased slightly (median absolute, -4.6 mm Hg; p = 0.09; relative, -21%; p = 0.07), whereas HP(5) did not change significantly (absolute increase, 3.6%; p = 0.51; median relative increase, 11%; p = 0.27). No significant associations were seen between changes in HP(5) or IFP and response to treatment (p = 0.2, relative HP(5) change and p = 0.14, relative IFP change). CONCLUSIONS: Celecoxib in combination with definitive CRT is associated with acceptable acute toxicity, but higher than expected late complications. Celecoxib is associated with a modest reduction in the angiogenic biomarker IFP, but this does not correspond with tumor response.

Adult↗

PubMed2006

Long-term performance of interstial fluid pressure and hypoxia as prognostic factors in cervix cancer.

OBJECTIVES: Hypoxia and high interstitial fluid pressure (IFP) have been shown to independently predict for nodal and distant metastases, as well as survival, in patients with cervix cancer. Using data from our prospective trial, we updated a cohort of patients treated with definitive radiation alone without chemotherapy, to assess the long-term prognostic impact of these microenvironmental features. METHODS: Between April 1994 and January 1999, 107 eligible patients with cervix cancer were entered into a prospective study of tumor oxygenation and IFP prior to primary radiation therapy. Oxygenation data are presented as the hypoxic proportion, defined as the percentage of pO(2) readings <5 mm Hg (abbreviated as HP(5)). Patients with HP(5) values >50% were considered to have hypoxic tumors. IFP is presented in mmHg, divided into high and low IFP groups by the median value. Patients ranged in age from 23 to 78 years with a mean of 53 years. The maximum tumor size ranged from 2 to 10 cm, with a median diameter of 5 cm. FIGO stage was IB in 28 patients, IIA in 4, IIB in 42 and IIIB in 33 patients. Twenty-two patients (21%) had evidence of pelvic lymph node involvement on staging CT abdomen/pelvis or MR pelvis. HP(5) ranged from 0% to 99% with a median of 48%. IFP ranged from -3 to 48 mm Hg (median 19 mm Hg). Median follow-up was 6.7 years (range 0.9-10.6). RESULTS: Disease-free survival (DFS) at 5 years was 50%. Five year DFS was 42% for patients with hypoxic tumors (HP(5)>50%), and 58% in patients with oxygenated tumors (HR 1.01 per %, p=0.05). DFS at 5 years was 42% for patients with interstitial hypertension (IFP >19 mm Hg), and 63% in patients with IFP <or=19 mm Hg (HR 1.05 per mmHg, p=0.001). In a multivariate analysis only tumor size (HR 1.2, p=0.009) pelvic nodal metastases (HR 3.3, p=0.0004) and IFP (HR 1.06, p=0.0005) were predictive of DFS. Because an interaction between nodal status and oxygenation was observed (p=0.03), further analysis indicated a borderline significant impact of HP(5) in addition to tumor size in node negative patients (HR 1.01, p=0.06). These results were similar when local or distant relapse was used as an endpoint. CONCLUSIONS: These results confirm our initial finding of the strong independent prognostic impact of IFP for relapse and survival in patients with cervix cancer. In contrast, the independent prognostic impact of HP(5) is of borderline significance and is limited to patients without imaging evidence of nodal metastases. However, these findings do not diminish the biologic significance of hypoxia, or the role of hypoxia and IFP as biomarkers of treatment response and as therapeutic targets.

Adult↗

PubMed2006

Dosimetric comparison of intensity-modulated, conformal, and four-field pelvic radiotherapy boost plans for gynecologic cancer: a retrospective planning study.

PURPOSE: To evaluate intensity-modulated radiation therapy (IMRT) as an alternative to conformal radiotherapy (CRT) or 4-field box boost (4FB) in women with gynecologic malignancies who are unsuitable for brachytherapy for technical or medical reasons. METHODS: Dosimetric and toxicity information was analyzed for 12 patients with cervical (8), endometrial (2) or vaginal (2) cancer previously treated with external beam pelvic radiotherapy and a CRT boost. Optimized IMRT boost treatment plans were then developed for each of the 12 patients and compared to CRT and 4FB plans. The plans were compared in terms of dose conformality and critical normal tissue avoidance. RESULTS: The median planning target volume (PTV) was 151 cm(3) (range 58-512 cm(3)). The median overlap of the contoured rectum with the PTV was 15 (1-56) %, and 11 (4-35) % for the bladder. Two of the 12 patients, both with large PTVs and large overlap of the contoured rectum and PTV, developed grade 3 rectal bleeding. The dose conformity was significantly improved with IMRT over CRT and 4FB (p < or = 0.001 for both). IMRT also yielded an overall improvement in the rectal and bladder dose-volume distributions relative to CRT and 4FB. The volume of rectum that received the highest doses (>66% of the prescription) was reduced by 22% (p < 0.001) with IMRT relative to 4FB, and the bladder volume was reduced by 19% (p < 0.001). This was at the expense of an increase in the volume of these organs receiving doses in the lowest range (<33%). CONCLUSION: These results indicate that IMRT can improve target coverage and reduce dose to critical structures in gynecologic patients receiving an external beam radiotherapy boost. This dosimetric advantage will be integrated with other patient and treatment-specific factors, particularly internal tumor movement during fractionated radiotherapy, in the context of a future image-guided radiation therapy study.

Dose Fractionation, Radiation↗

PubMed2006

Effects of the vascular disrupting agent ZD6126 on interstitial fluid pressure and cell survival in tumors.

Interstitial fluid pressure (IFP) is elevated in tumors due to abnormal vasculature, lack of lymphatic drainage, and alterations in the tumor interstitium. ZD6126 is a tubulin-binding agent that selectively disrupts tumor vasculature resulting in tumor necrosis. This study examined the effect of ZD6126 on tumor IFP and the response of tumors with different IFP levels to ZD6126. Pretreatment IFP was measured using the wick-in-needle method in tumors (murine KHT-C and human CaSki) growing i.m. in the hind legs of mice. Mice were treated i.p. with a single dose of ZD6126 (100 or 200 mg/kg) and posttreatment IFP measurements were made. Blood flow imaging was conducted using Doppler optical coherence tomography, whereas oxygen partial pressure was measured using a fiber optic probe. Clonogenic assays were done to determine tumor cell survival. In KHT-C tumors, IFP dropped significantly at 1 hour posttreatment, returned to pretreatment values at 3 hours, and then declined to approximately 25% of the pretreatment values by 72 hours. In CaSki tumors, the IFP decreased progressively, beginning at 1 hour, to approximately 30% of pretreatment values by 72 hours. Clonogenic cell survival data indicated that ZD6126 was less effective in tumors with high IFP values (>25 mm Hg). Vascular disrupting agents, such as ZD6126, can affect IFP levels and initial IFP levels may predict tumor response to these agents. The higher cell survival in high IFP tumors may reflect greater microregional blood flow limitations in these tumors and reduced access of the drug to the target endothelial cells.

Animals↗

PubMed2005

Comparison of late toxicity between continuous low-dose-rate and pulsed-dose-rate brachytherapy in cervical cancer patients.

PURPOSE: To compare survival and severe late radiation toxicity between patients who received continuous low-dose-rate (LDR) brachytherapy (BT) and pulsed-dose-rate (PDR) BT for cervical cancer. METHODS AND MATERIALS: A retrospective review of cervical cancer patients who underwent primary radiotherapy with or without concurrent cisplatin was performed. Late Grade 3 or worse toxicities were assessed using the National Cancer Institute Common Toxicity Criteria. The study endpoints were overall and disease-free survival and the probability of severe late toxicity. RESULTS: A total of 109 patients (65.7%) received LDR BT and 57 (34.3%) received PDR BT. Seventy patients received concurrent chemotherapy with cisplatin. The 3-year overall survival and disease-free survival rate was 70% and 57% for the LDR group and 82% and 70% for the PDR group, respectively (p = 0.25 and p = 0.19). The 3-year probability rate for late Grade 3 or worse toxicity was 7.4% for LDR BT patients and 7.6% for PDR BT patients, respectively (p = 0.69) and 6.9% and 7.6%, respectively, for concurrent chemotherapy vs. none (p = 0.69). CONCLUSION: No difference was found in severe late toxicity, overall survival, or disease-free survival between the LDR and PDR groups.

Adult↗

PubMed2005

Assessment of the tumor microenvironment in cervix cancer using dynamic contrast enhanced CT, interstitial fluid pressure and oxygen measurements.

PURPOSE: Interstitial fluid pressure (IFP) and oxygen (pO(2)) measurements are prognostic factors in cervical cancer. The purpose of this study was to determine the relationship between IFP and oxygenation and parameters derived from dynamic contrast-enhanced computed tomography (DCE-CT). METHODS AND MATERIALS: Dynamic contrast-enhanced computed tomography was performed in 32 patients with cervical cancer before radiation therapy. Images were acquired during intravenous contrast injection at 1 per s for 120 s and 1 per 15 s for 60 s. DCE-CT was analyzed using CT Perfusion 3 software (GE Medical Systems) to derive tumor blood flow (BF), permeability surface area product, blood volume, and mean transit time. Further analysis was performed to obtain relative peak enhancement, residual enhancement at 3 min after contrast injection (RE), time to peak and initial slope. Nodal status and tumor size were assessed with MRI. From in vivo IFP (n = 31) and pO(2) (n = 31) tumor measurements median pO(2) (mO(2)), percentage measurements less than 5 mm Hg (HP5) and mean IFP values were calculated. RESULTS: There was a positive correlation between BF and mO(2) (r = 0.47, p = 0.007) and between RE and HP5 (r = 0.39, p = 0.03). There was no correlation between IFP and DCE-CT parameters. CONCLUSION: There is a moderately positive, correlation between tumor oxygenation and BF as well as RE and HP5. Further study is required to determine if DCE-CT parameters are useful predictors of tumor behavior in cervical cancer.

Extracellular Fluid↗

PubMed2005

Consolidative abdominopelvic radiotherapy after surgery and carboplatin/paclitaxel chemotherapy for epithelial ovarian cancer.

PURPOSE: To assess the feasibility and morbidity of sequential cytoreductive surgery, carboplatin/paclitaxel chemotherapy, and consolidative abdominopelvic radiotherapy (APRT) in ovarian cancer. METHODS AND MATERIALS: Between 1998 and 2000, 29 patients with optimally cytoreduced epithelial ovarian cancer were treated with carboplatin (135 mg/m2) and paclitaxel (area under the curve [AUC] of 6) followed by APRT in a prospective protocol. All patients were clinically, radiographically, and biochemically (CA-125) free of disease at the completion of chemotherapy. Abdominopelvic radiotherapy was delivered using 6 MV anterior-posterior photon fields to encompass the peritoneal cavity. Median follow-up was 4 years. RESULTS: Two patients experienced Radiation Therapy Oncology Group Grade 3 gastrointestinal toxicity during APRT; 6 patients, Grade 3 or 4 neutropenia; and 3 patients, Grade 3 or 4 thrombocytopenia. Overall, 10 patients had Grade 3 or 4 acute toxicity. All of the acute side effects resolved after treatment was completed, and there were no serious consequences such as sepsis or hemorrhage. Abdominopelvic radiotherapy was abandoned prematurely in 3 patients. Late side effects were seen in 5 patients, including 1 small bowel obstruction, 2 symptomatic sacral insufficiency fractures, 1 case of severe dyspareunia, and 1 case of prolonged fatigue. All resolved with supportive management. The 4-year actuarial disease-free survival was 57%, and the overall survival was 92%. Eleven of 12 patients who relapsed received salvage chemotherapy, which was well tolerated. CONCLUSIONS: Abdominopelvic radiotherapy after optimal surgery and carboplatin/paclitaxel chemotherapy is associated with an acceptable risk of acute and late side effects and does not limit subsequent salvage chemotherapy. Consolidative APRT warrants further investigation as a means of improving the outcome of patients with ovarian cancer.

Adult↗

PubMed2005

Relations between non-protein sulfydryl levels in the nucleus and cytoplasm, tumor oxygenation, and clinical outcome of patients with uterine cervical carcinoma.

PURPOSE: The non-protein sulfydryls (NPSH) glutathione and cysteine are able to effect chemical repair of radiation-induced DNA damage, particularly under hypoxic conditions, and are implicated in radioresistance. The levels of NPSH in the nucleus are predicted to be more important than those in cytoplasm. We, therefore, investigated the relation between nuclear NPSH and the clinical outcome of radical radiotherapy (RT). METHODS AND MATERIALS: A fluorescence image analysis technique to measure nuclear NPSH was developed, based on the SH-reactive probe 1(4-chloromercuryphenyl-azo-2-naphthol) and the DNA dye 4,6-diamidino-2-phenylindole. This was used to measure nuclear and tissue NPSH levels in biopsies obtained from 58 patients with locally advanced uterine cervical carcinoma, treated with radical RT. RESULTS: An approximately twofold range in the nuclear and tissue NPSH levels between individual tumors was found, although the intratumoral heterogeneity was much smaller. Nuclear and tissue NPSH values correlated closely in all cases. No statistically significant associations were noted between NPSH levels and tumor size, stage, or tumor hypoxia as determined at the time of biopsy using an Eppendorf po(2) probe. The response to RT and patient survival did not correlate with tumor NPSH. CONCLUSION: These results did not support the existence of an independently regulated nuclear pool of NPSH and showed that tissue and nuclear NPSH are not predictive of the outcome of patients with locally advanced cervical carcinomas treated with RT.

Cell Nucleus↗

PubMed2005

A phase II study of localized prostate cancer treated to 75.6 Gy with 3D conformal radiotherapy.

BACKGROUND AND PURPOSE: To prospectively evaluate toxicity, biochemical failure-free survival (bFFS) and biopsy-proven local control for prostate cancer patients treated with 75.6 Gy in 42 fractions using 6-field conformal radiotherapy to prostate alone. PATIENTS AND METHODS: From 1997 to 1999, 140 patients with T1-2NxM0, Gleason score or=grade 2: 2%, and GU>or=grade 2: 1%. The 3-year bFFS of patients failure-free before biopsy was 93% (95% CI: 83-100) from a negative biopsy and 22% (95% CI: 0-56) from a positive biopsy (P=0.001). Patients reported significantly more late toxicity than physicians (GI: P=0.003, GU: P<0.001). At 5.0 years median follow-up, cause-specific survival was 98% (95% CI: 96-100), overall survival was 91% (95% CI: 86-97), and bFFS was 55% (95% CI: 45-64). CONCLUSIONS: 75.6 Gy caused modest levels of acute and late toxicity. Three-year biopsies predicted subsequent biochemical outcome.

Adenocarcinoma↗

PubMed2004

Polarographic electrode study of tumor oxygenation in clinically localized prostate cancer.

PURPOSE: To describe the oxygenation of clinically localized prostate cancer. METHODS AND MATERIALS: Intraprostatic oxygen tension was measured using the Eppendorf electrode in 55 unanesthetized men with localized prostate cancer before radiotherapy. Measurements were made along two tracks through regions of suspected tumor in the prostate, and core needle biopsies were then obtained from the same regions. RESULTS: The median pO(2) ranged from 0.2 to 57.3 mm Hg, and the grand median pO(2) was 4.5 mm Hg. The percentage of oxygen readings <5 mm Hg (HP(5)) ranged from 0% to 100% (median 60%). The track 1 oxygen readings were greater than those from track 2. Statistically significant heterogeneity was found in the individual oxygen readings: the between- and within-tumor components accounted for 32% and 68% of the total variability, respectively. However, the between-tumor variability in HP(5) significantly exceeded the within-tumor variability (61% vs. 39%). No association was found between oxygen values and clinical factors, including age, T stage, Gleason score, prostate-specific antigen level, hemoglobin concentration, or prior hormonal treatment. No difference was noted in the oxygenation between regions of tumor and normal prostate tissue, as determined from the core biopsies. CONCLUSION: Localized prostate cancer is characterized by marked hypoxia and significant heterogeneity in oxygenation, similar to other human tumors. The normal prostate may contain regions of low oxygen concentration. HP(5), as determined in this study, should adequately discriminate among patients with prostate cancer and allow the independent prognostic significance of oxygenation to be evaluated once the study matures.

Aged↗

PubMed2004

A randomized trial of supine vs. prone positioning in patients undergoing escalated dose conformal radiotherapy for prostate cancer.

BACKGROUND AND PURPOSE: The optimal treatment position for patients receiving radical radiation therapy for prostate cancer has been a source of controversy. To resolve this issue, we conducted a randomized trial to evaluate the effects of supine and prone positioning on organ motion, positioning errors, and dose to critical organs during escalated dose conformal irradiation for localized prostate cancer and patient and therapist satisfaction with setup technique. PATIENTS AND METHODS: Twenty eight patients were randomized to commence treatment immobilized in the supine or prone position and were subsequently changed to the alternate positioning for the latter half of their treatment. Patients underwent CT simulation and conformal radiotherapy planning and treatment in both positions. The clinical target volume encompassed the prostate gland. Alternate day lateral port films were compared to corresponding simulator radiographs to measure the isocentre positioning errors (IPE). Prostate motion (PM) and total positioning error (TPE) were measured from the same films by the displacements of three implanted fiducial markers. Dose volume histograms (DVHs) for the two treatment positions were compared at the 95, 80 and 50% dose (D%) levels. The patients and radiation therapists completed weekly questionnaires regarding patient comfort and ease of setup. RESULTS: Seven patients, who started in the supine position, subsequently refused prone position and received their whole treatment supine. Small bowel in the treatment volume, not present in the supine position, prevented one patient from being treated prone. PM in anterior posterior direction was statistically significantly less in the supine position (P<0.05). There was no significant difference in superior inferior PM for the two treatment positions. No statistically significant difference between supine and prone positioning was observed in isocentre positioning error (IPE) or total positioning error (TPE) due to a policy of daily pre-treatment correction. However, more pre-treatment corrections were required for patients in the prone position. The DVH analysis demonstrated larger volumes of the bladder wall, rectal wall and small bowel within the D95, D80 and D50% when comparing the planning target volumes (PTVs) actually treated for prone positioning. When the prone PTV was expanded to account for the greater PM encountered in that position, a statistically significant difference (P<0.007) was observed in favour of the supine position at all dose levels. In the prone position, four patients had small bowel within the 60 Gray (Gy) isodose and in the supine position, no patients had small bowel in the 60 or 38Gy volumes. Supine position was significantly more comfortable for the patients and setup was significantly easier for the radiation therapists. The median patient comfort score was 0.79 (Standard deviation (SD) 0.03) supine and 0.45 (SD 0.05) prone (P<0.001) The therapist convenience of setup was 0.80 (SD 0.016) supine and 0.54 (SD 0.025) prone (P<0.005). No statistically significant difference was seen for the other parameters studied. CONCLUSIONS: We demonstrated significantly less PM in the supine treatment position. There was no difference for either treatment position in IPE or TPE, however, more pre-treatment corrections were required in the prone position. Prone position required a larger PTV with resulting increased dose to critical organs. There were statistically significant improvements at all dose levels for small bowel, rectal wall and bladder wall doses in the supine position once corrections were made for differences in organ motion. Linear analogue scores of patient comfort and radiation therapist convenience demonstrated statistically significant improvement in favour of the supine position. Supine positioning has been adopted as the standard for conformal prostatic irradiation at our centre.

Aged↗

PubMed2004

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 (45Gy to midplane in 20 daily fractions) at a dose of 0.45 g/m(2), as well as during intra-uterine brachytherapy (40Gy). 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.

Adenocarcinoma↗

PubMed2004

The human tumor microenvironment: invasive (needle) measurement of oxygen and interstitial fluid pressure.

Invasive needle-based assessments of the extracellular environment in human tumors have yielded important prognostic information that has shaped the direction of future translational research and begun to influence clinical practice. This review focuses on electrode measurements of oxygenation in human tumors, particularly in relation to the practicalities of applying these techniques in the clinic and the relationship to patient outcome. Elevated tumor interstitial fluid pressure (IFP) has been shown to be an important independent prognostic factor in cervix cancer. The pathophysiology of elevated IFP is discussed, along with possible explanations for the strong influence on patient outcome and directions for future research.

Cell Hypoxia↗

PubMed2004

Up-regulation of the redox mediators thioredoxin and apurinic/apyrimidinic excision (APE)/Ref-1 in hypoxic microregions of invasive cervical carcinomas, mapped using multispectral, wide-field fluorescence image analysis.

Thioredoxin and apurinic/apyrimidinic excision (APE)/ref-1 are important redox mediators in biochemical pathways that promote cell survival under adverse conditions including hypoxia and oxidative stress. For example, elevated levels occur surrounding vascular infarcts and protect from reperfusion injury. Because elevated thioredoxin or APE/ref-1 is also associated with resistance to certain forms of cancer treatment, we examined their tissue distribution in a series of 110 cervical carcinoma biopsies. Analysis was done using a quadruple fluorescence imaging technique, incorporating carbonic anhydrase IX (CAIX) immunofluorescence to outline hypoxic microregions and 4',6-diamidino-2-phenylindole to localize nuclear staining of thioredoxin and APE/ref-1. A scanning autostage was used to image the entire tissue section. Thioredoxin and APE/ref-1 levels were expressed as the average pixel brightness in tumor tissue, subdivided based on CAIX and 4',6-diamidino-2-phenylindole staining. Results showed that the nuclear and cytoplasmic levels of thioredoxin were similar, whereas APE/ref-1 expression was greater in nuclei. Neither of these markers was predictive of outcome in this series of patients treated with radical radiotherapy. Both proteins showed highly significant elevations in CAIX-positive regions compared to CAIX-negative regions, and there was a nonsignificant trend for this effect to be greater in adenocarcinomas compared to squamous cell carcinomas. Levels of APE/ref-1 decreased with increasing tumor grade, but the expression was similar in CAIX-positive regions of poorly differentiated tumors compared to moderately or well-differentiated tumors. Elevated expression of thioredoxin and APE/ref-1 might promote cancer cell survival in hypoxic microenvironments of cervical carcinomas.

Adult↗

PubMed2003

Carbonic anhydrase IX expression, hypoxia, and prognosis in patients with uterine cervical carcinomas.

PURPOSE: Hypoxia is associated with adverse outcome for a number of solid tumors, including cervical carcinomas. Direct pO(2) measurement requires specialized equipment and expertise that is not generally available. Immunohistochemical measurement of intrinsic tissue markers of hypoxia is an alternative approach. Recent studies suggest that carbonic anhydrase IX (CA IX), which is regulated via hypoxia-inducible factor 1, is a useful intrinsic marker of tumor hypoxia. EXPERIMENTAL DESIGN: Biopsies were obtained from 110 patients with locally advanced cervical carcinoma treated with radiotherapy or chemoradiotherapy. Tissue sections were labeled using an immunofluorescence technique and CA IX expression in the viable tumor area measured using a semiautomated fluorescence image analysis technique. Results were compared with direct pO(2) values obtained using an Eppendorf probe and to patient outcome. Intratumoral heterogeneity of CA IX expression was examined in a subgroup of patient who underwent multiple biopsies. RESULTS: The median percentage of tumor area staining for CA IX was 3.56 (range, 0.01-58.85). CA IX staining did not correlate with the Eppendorf pO(2) measurements. Whereas the latter values were predictive of patient outcome, the CA IX levels were not. Measurement of CA IX in multiple biopsies indicated that intratumoral heterogeneity accounted for 41% of the total variance in the data set. CONCLUSIONS: In contrast to some recent studies, we did not find significant associations between CA IX expression and tumor pO(2) levels or patient outcome in locally advanced carcinomas of the cervix. Probable explanations relate to the problems of sampling error using single biopsies and the existence of biological factors other than hypoxia that influence CA IX levels.

Adult↗

PubMed2003

Pretreatment proliferation parameters do not add predictive power to clinical factors in cervical cancer treated with definitive radiation therapy.

PURPOSE: To examine the prognostic value of tumor proliferation measurements in women with carcinoma of the uterine cervix. We report an update of a prospective study focusing on whether pretreatment proliferation parameters are associated with clinical outcome, relative to other established clinical factors. MATERIALS AND METHODS: One hundred and one patients were recruited into the study from years 1991 to 1999. The LI for in vivo bromodeoxyuridine incorporation by the tumor and the potential doubling time (T(pot)) were determined by flow cytometry (fc). LI and its staining pattern were also assessed by immunohistochemistry (ih) using tissue sections. Apoptosis was assessed histologically using morphological criteria. Patients were treated with definitive radiation therapy. RESULTS: A successful fc measurement for LI-fc and T(pot) was possible in 95 patients (94%). The median/mean LI-fc was 6.6/7.6% (range 1.4-36.1%), and for LI-ih, 10.8/11.5%. To date, 43 patients have died of disease, and the median follow-up for alive patients is 6.2 years (range 1.3-9.3 years). Among 88 patients who completely responded to treatment, 40 patients have relapsed (14 pelvic, 23 distant, and 3 pelvic and distant). In univariate analysis, the significant factors for adverse disease-free survival were large tumor size (P = 0.0001), low hemoglobin (P = 0.001), pelvic lymph node status (P = 0.004), stage (P = 0.013), and overall treatment time (P = 0.0008). In multivariate analysis, only tumor size, pelvic lymph node status, and overall treatment time remained significant for disease-free survival. LI-fc, LI-ih, T(pot), ploidy, pattern of bromodeoxyuridine staining, and apoptosis were not significantly associated with clinical outcome in univariate or multivariate analyses. CONCLUSIONS: These mature data indicate that none of the pretreatment proliferation parameters have prognostic significance in the radical radiotherapy of carcinoma of the uterine cervix, despite the significance of overall treatment time for treatment outcome.

Adenocarcinoma↗

PubMed2003

Salvage radiotherapy following radical prostatectomy.

Biochemical relapse will occur in 17-64% of men who undergo radical prostatectomy, and up to a third of men with biochemical relapse will progress to develop metastatic disease and ultimately die of prostate cancer. Postoperative salvage radiotherapy (RT) to the prostatic fossa is well-tolerated and potentially curative treatment and should be considered for all men who have biochemical relapse following prostatectomy. Gleason score <8, prostate-specific antigen (PSA) doubling time >10 months and PSA re-emergence >2 years following surgery predict for a low risk of early metastatic failure, but even men with no favourable prognostic factors may have a long-term durable response to RT and should not be excluded from consideration of treatment on the basis of these factors alone. Positive surgical margin status and a positive anastomotic biopsy do not predict response to RT, and routine biopsy is not recommended. PSA level at time of RT is a strong indicator of durable response to RT. No one PSA cutpoint level appears to be more significant, and early RT is likely more effective than late. Contemporary PSA assays can detect biochemical relapse in the 0.01-0.2 range, and this may provide additional therapeutic advantage if treatment can be given when tumour burden is smallest. There is an urgent need for prospective data from randomised trials to optimally select patients for salvage RT, to determine the optimal time to initiate treatment and to determine the role of adjuvant hormone therapy, and all patients should be considered for entry into ongoing and future clinical trials.

Humans↗