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Andrew C von Eschenbach

Publications and source records attributed to Andrew C von Eschenbach.

10 recordsLinked to original sources
PubMed2004

A vision for the National Cancer Program in the United States.

The intersection of two noble endeavors - the scientists' quest to understand life itself and the physicians' dedication to relieve suffering and prolong life - came into sharp focus in 1971 with the United States National Cancer Act. This focus has led to an exponential expansion of our understanding of cancer at the genetic, molecular and cellular levels, and concomitant advances in our ability to disrupt the disease process through prevention, early detection and successful treatment. At the National Cancer Institute we are committed to capitalize on these achievements. A new era is now within our grasp, a time when no one suffers or dies as a result of cancer.

Animals↗
PubMed2003

Molecular markers of outcome after radiotherapy in patients with prostate carcinoma: Ki-67, bcl-2, bax, and bcl-x.

BACKGROUND: Abnormal expression of key proteins of the apoptotic pathway has been associated with poor prognosis, although there have been few studies of these correlations in patients with prostate carcinoma who are treated with radiotherapy. The current study examined the association between expression levels of Ki-67, bcl-2, bax, and bcl-x in pretreatment biopsy specimens and patient outcome after definitive radiotherapy alone. METHODS: Archival pretreatment prostate biopsy tumor tissue was retrieved from 106 patients with Stage T1-T3 prostate carcinoma who were treated at the University of Texas M. D. Anderson Cancer Center with external beam radiotherapy between 1987 and 1993. Expression levels of Ki-67 (MIB-1 staining; n = 106 patients), bcl-2 (n = 77 patients), bax (n = 70 patients), and bcl-x (both long and short splice variants; n = 72 patients) were determined by immunohistochemical staining. The Ki-67 labeling index (Ki67-LI) was available for all patients and was derived from the percentage of Ki-67 positive cells. Biochemical failure after radiotherapy was defined as three consecutive rises in prostate specific antigen level on follow-up. The median follow-up was 62 months. RESULTS: High Ki67-LI (> 3.5%) expression was observed in 33% of patients, overexpression of bcl-2 was observed in 16% of patients, altered bax expression was observed in 23% of patients, and altered bcl-x expression was observed in 53% of patients. There was no correlation found between the biomarkers. Kaplan-Meier survival estimates of freedom from biochemical failure (bNED) and the log-rank test revealed significantly lower rates in association with high Ki67-LI, positive bcl-2, and altered bax staining. No correlation was observed between bcl-x staining and bNED. Cox proportional hazards multivariate analysis confirmed that bcl-2 and bax were independent of pretreatment PSA level, Gleason score, disease stage, and Ki67-LI in predicting bNED. CONCLUSIONS: Abnormalities in the expression levels of bcl-2 and bax were associated with increased failure after patients were treated for prostate carcinoma with external beam radiotherapy. These biomarkers appeared to be useful in categorizing patient risk further, beyond Ki-67 staining and conventional clinical prognostic factors.

Biomarkers, Tumor↗
PubMed2002

Prostate cancer radiation dose response: results of the M. D. Anderson phase III randomized trial.

PURPOSE: A randomized radiotherapy dose escalation trial was undertaken between 1993 and 1998 to compare the efficacy of 70 vs. 78 Gy in controlling prostate cancer. METHODS AND MATERIALS: A total of 305 Stage T1-T3 patients were entered into the trial and, of these, 301 with a median follow-up of 60 months, were assessable. Of the 301 patients, 150 were in the 70 Gy arm and 151 were in the 78 Gy arm. The primary end point was freedom from failure (FFF), including biochemical failure, which was defined as 3 rises in the prostate-specific antigen (PSA) level. Kaplan-Meier survival analyses were calculated from the completion of radiotherapy. The log-rank test was used to compare the groups. Cox proportional hazard regression analysis was used to examine the independence of study randomization in multivariate analysis. RESULTS: There was an even distribution of patients by randomization arm and stage, Gleason score, and pretreatment PSA level. The FFF rates for the 70- and 78 Gy arms at 6 years were 64% and 70%, respectively (p = 0.03). Dose escalation to 78 Gy preferentially benefited those with a pretreatment PSA >10 ng/mL; the FFF rate was 62% for the 78 Gy arm vs. 43% for those who received 70 Gy (p = 0.01). For patients with a pretreatment PSA 10 ng/mL who were treated to 78 Gy (98% vs. 88% at 6 years, p = 0.056). Rectal side effects were also significantly greater in the 78 Gy group. Grade 2 or higher toxicity rates at 6 years were 12% and 26% for the 70 Gy and 78 Gy arms, respectively (p = 0.001). Grade 2 or higher bladder complications were similar at 10%. For patients in the 78 Gy arm, Grade 2 or higher rectal toxicity correlated highly with the proportion of the rectum treated to >70 Gy. CONCLUSION: An increase of 8 Gy resulted in a highly significant improvement in FFF for patients at intermediate-to-high risk, although the rectal reactions were also increased. Dose escalation techniques that limit the rectal volume that receives >or=70 Gy to <25% should be used.

Aged↗
PubMed2002

Ki-67 staining is an independent correlate of biochemical failure in prostate cancer treated with radiotherapy.

PURPOSE: To determine the significance of Ki-67/MIB1 staining as a marker of patient outcome for prostate cancer patients treated with radiotherapy. EXPERIMENTAL DESIGN: Pretreatment archival prostate biopsy tumor tissue was available from 106 stage T1-T4 prostate cancer patients treated with external beam radiotherapy between 1987 and 1993 at M. D. Anderson Cancer Center. Diagnosis was made from prostate needle biopsy in 64 cases and from transurethral resection of the prostate (TURP) in 42 cases. All patients had a pretreatment prostate-specific antigen (PSA), and no patient had evidence of metastasis. Immunohistochemical staining for MIB1 was used to determine the percentage of Ki-67-positive tumor cells, the Ki-67 labeling index (Ki67-LI). Biochemical failure after radiotherapy was defined as three rises in PSA on follow-up. Median follow-up was 62 months. RESULTS: The mean and median Ki67-LI for the entire cohort was 3.2 and 2.3. The mean and median Ki67-LIs for those diagnosed by needle biopsy were 3.2 and 2.3, and by TURP were 3.1 and 2.4. For all patients, mean Ki67-LI levels were significantly higher with stage T3/T4 disease, Gleason 7-10 disease, and in those that developed treatment failure. Similar relationships were observed when the Ki67-LI was dichotomized into low (< or =3.5%) and high (>3.5%) groups. Actuarial freedom from biochemical failure (bNED) when Ki67-LI was low and high was 76 and 33% at 5 years (P < 0.0001, log rank). Similar statistically significant differences were observed when the TURP and needle biopsy groups were analyzed separately. Cox proportional hazards regression showed that dichotomized Ki67-LI was an independent correlate of bNED, along with pretreatment PSA, Gleason score, and clinical stage. CONCLUSIONS: The Ki67-LI obtained from pretreatment prostate cancer tissue is a strong independent predictor of failure after radiotherapy using biochemical criteria. This prognostic factor was equally valuable for patients diagnosed by TURP or needle biopsy.

Biomarkers, Tumor↗
PubMedDate not supplied

American Cancer Society guidelines for the early detection of cancer.

Each year the American Cancer Society publishes a summary of existing recommendations for early cancer detection, including updates, and/or emerging issues that are relevant to screening for cancer. In last year's article, the guidelines regarding screening for the early detection of prostate, colorectal, and endometrial cancers were updated, as was the narrative pertaining to testing for early lung cancer detection. Although none of the ACS's guidelines were updated in 2001, work is proceeding on an update of screening recommendations for breast and cervical cancer and an update of these guidelines will be announced in the January/February 2003 issue of CA. As in previous issues, we review recommendations for the "cancer-related check-up," in which clinical encounters provide case-finding and health counseling opportunities. Finally, we provide an update of the most recent data pertaining to participation rates in cancer screening by age, gender, and ethnicity from the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System (BRFSS) and National Health Interview Survey (NHIS).

Breast Neoplasms↗