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Biomedical subjects

C G Willett

Publications and source records attributed to C G Willett.

At least 37 records · Page 2Linked to original sources
PubMed1998

Changes in tumor proliferation of rectal cancer induced by preoperative 5-fluorouracil and irradiation.

PURPOSE: This study examines the effect of 5-fluorouracil administration during preoperative irradiation on rectal cancer tumor proliferation. PATIENTS AND METHODS: One hundred and fifty-three patients with locally advanced rectal cancer received 45 to 50 Gy of preoperative irradiation with (103 patients) and without (50 patients) concurrent 5-fluorouracil, followed by surgery. Pretreatment tumor biopsies and postirradiation surgical specimens were scored for proliferative activity by assaying the extent of Ki-67 and proliferating cell nuclear antigen immunostaining and the number of mitoses per ten high-powered fields. Postirradiation specimens were also assessed for downstaging. RESULTS: Although 5-fluorouracil did not improve downstaging rates, marked decreases in the activity of all three markers of proliferation (mitotic counts, Ki-67, and proliferating cell nuclear antigen immunostaining) were seen in rectal cancers of patients receiving the drug. No significant decreases were noted in patients undergoing irradiation only. CONCLUSION: The addition of 5-fluorouracil to preoperative irradiation resulted in a more complete inactivation of the proliferating population. Frequency of downstaging, however, was unaffected. Thus, the quiescent cell population appears to represent a substantial barrier to further downstaging. New treatment strategies should be aimed at controlled recruitment of quiescent tumor cells at the time of irradiation.

Adult↗
PubMed1998

Sphincter preservation in rectal cancer. Local excision followed by postoperative radiation therapy.

The management of distal rectal cancer is in evolution. Although abdominoperineal resection has been long regarded as the definitive treatment of distal rectal cancer, it is associated with significant morbidity--loss of anorectal function with a permanent colostomy and a high incidence of sexual and genitourinary dysfunction. To overcome these limitations, innovative efforts are underway studying the feasibility and efficacy of a variety of sphincter-preserving operations, usually in combination with radiation therapy and chemotherapy. Local excision procedures with adjuvant therapy represent one such treatment strategy that attempts to optimize local control and survival with preservation of sphincter integrity. This article summarizes the current role of local excision and postoperative irradiation and chemotherapy for patients with carcinoma of the rectum.

Abdomen↗
PubMed1998

The impact of 5-fluorouracil and intraoperative electron beam radiation therapy on the outcome of patients with locally advanced primary rectal and rectosigmoid cancer.

OBJECTIVE: To analyze the effects of 5-fluorouracil (5-FU) chemotherapy combined with preoperative irradiation and the role of intraoperative electron beam irradiation (IOERT) on the outcome of patients with primary locally advanced rectal or rectosigmoid cancer. METHODS: From 1978 to 1996, 145 patients with locally advanced rectal cancer underwent moderate- to high-dose preoperative irradiation followed by surgical resection. Ninety-three patients received 5-FU as a bolus for 3 days during the first and last weeks of radiation therapy (84 patients) or as a continuous infusion throughout irradiation (9 patients). At surgery, IOERT was administered to the surgical bed of 73 patients with persistent tumor adherence or residual disease in the pelvis. RESULTS: No differences in sphincter preservation, pathologic downstaging, or resectability rates were observed by 5-FU use. However, there were statistically significant improvements in 5-year actuarial local control and disease-specific survival in patients receiving 5-FU during irradiation compared with patients undergoing irradiation without 5-FU. For the 73 patients selected to receive IOERT, local control and disease-specific survival correlated with resection extent. For the 45 patients undergoing complete resection and IOERT, the 5-year actuarial local control and disease-specific survival were 89% and 63%, respectively. These figures were 65% and 32%, respectively, for the 28 patients undergoing IOERT for residual disease. The overall 5-year actuarial complication rate was 11%. CONCLUSIONS: Treatment strategies using 5-FU during irradiation and IOERT for patients with locally advanced rectal cancer are beneficial and well tolerated.

Actuarial Analysis↗
PubMed1998

Macrophage-stimulating protein and its receptor in non-small-cell lung tumors: induction of receptor tyrosine phosphorylation and cell migration.

Previously, we identified macrophage-stimulating protein (MSP) as being expressed during hamster lung injury induced by nitrosamine carcinogens. Transient, generalized epithelial-cell hyperplasia during the preneoplastic period, and eventually nonneuroendocrine (non-NE) lung tumors, are known to develop in these nitrosamine-treated hamsters. We wished to test the hypothesis that MSP and its tyrosine kinase receptor, RON, might represent an autocrine/paracrine system involved in the pathogenesis of human nonneuroendocrine lung tumors, the non-small-cell carcinomas (NSCLCs). We found that this occurred in a paracrine fashion in three of eight primary human NSCLCs that expressed messenger RNA (mRNA) for MSP at high levels in histologically normal lung adjacent to the tumor, but not in the primary tumor, together with mRNA for RON in both normal and tumor tissue. MSP and RON could also constitute an autocrine/paracrine system in human NSCLC cell lines: five of 16 cell lines (squamous and adenosquamous) expressed both MSP and RON; and an additional five of 16 cell lines expressed RON without detectable MSP. Although three cases of primary squamous-cell carcinomas expressed MSP (two of three in the tumor and one of three in nonneoplastic lung), mRNA for RON was not detectable in these cases. RON was functional in all tested RON mRNA-positive cell lines, with exogenous MSP inducing RON-mediated tyrosine phosphorylation. Treatment of a RON-positive adenosquamous carcinoma cell line with MSP additionally resulted in increased motility in a cell-migration assay, suggesting that MSP might promote cell migration of some NSCLCs. In conclusion, MSP and RON might represent an autocrine/paracrine system involved in the pathogenesis of lung cancer, although the nature of the biologic responses in different cell types might vary considerably.

Carcinoma, Non-Small-Cell Lung↗
PubMed1997

Time-dose considerations in the treatment of anal cancer.

PURPOSE: To analyze the impact of patient and treatment parameters in concurrent chemoradiation treatment for anal carcinoma. METHODS AND MATERIALS: Retrospective review of 50 MO anal cancer patients treated from 1984-1994. Most patients received concurrent 5-FU, mitomycin, and radiation. Local control and disease-free/overall survival were determined and analyzed according to patient and treatment parameters. RESULTS: With 43 month median follow-up, projected overall survival is 66% at 5 and 8 years. Disease-free survival is 67% at 5 years and 59% at 8 years. Local control is 70% at 5 and 8 years. Doses of > or =54 Gy are associated with improved 5-year survival (84 vs. 47%, p = 0.02), disease-free survival (74 v. 56%, p = 0.09), and local control (77 vs. 61%, p = 0.04). Although local control, disease-free survival, and overall survival were improved in patients whose overall treatment time was <40 days, this was not statistically significant. Outcome in the four patients with pretreatment hemoglobin (Hgb) <10 appeared worse with 3-year overall survival 50 vs. 68% (p = 0.07), disease-free survival 0 vs. 67% (p = 0.11), and local control 0 vs. 74% (p = 0.05). Projected 5-year overall survival, relapse-free survival, and local control in 4 HIV(+) patients is 0, 75, and 75%. Multivariate analysis reveals that dose (p = 0.02) and Hgb (p = 0.05) independently affect local control, dose (p = 0.02) affects disease-free survival, and dose (p = 0.01), Hgb (p = 0.03), T-stage (p = 0.03), and HIV-status (0.07) independently influence overall survival. CONCLUSION: Radiation doses of > or =54 Gy are associated with significantly improved survival and local control in anal cancer patients treated with chemoradiation. Overall treatment times of less than 40 days are associated with a trend towards improved outcome, but this is not significant. Pretreatment hemoglobin <10 is associated with worse treatment outcome. Survival of HIV (+) patient is poor, but the majority of such patients in this series died of intercurrent disease with their anal carcinomas controlled by chemoradiation.

Adult↗
PubMed1997

Differential screening of a human chromosome 3 library identifies hepatocyte growth factor-like/macrophage-stimulating protein and its receptor in injured lung. Possible implications for neuroendocrine cell survival.

Transient pulmonary neuroendocrine cell hyperplasia and non-neuroendocrine lung tumors develop in nitrosaminetreated hamsters, which we hypothesized might modulate epithelial cell phenotype by expressing gene(s) homologous to human chromosome 3p gene(s) deleted in small cell carcinoma of the lung (SCLC). We differentially screened a chromosome 3 library using nitrosamine-treated versus normal hamster lung cDNAs and identified hepatocyte growth factor-like/macrophage-stimulating protein (HGFL/MSP) in injured lung. HGFL/MSP mRNA is low to undetectable in human SCLC and carcinoid tumors, but the HGFL/MSP tyrosine kinase receptor, RON, is present and functional on many of these neuroendocrine tumors. In H835, a pulmonary carcinoid cell line, and H187, a SCLC cell line, HGFL/ MSP induced adhesion/flattening and apoptosis. Using viable cell counts to assess proliferation after 14 d of treatment with HGFL/MSP, there is growth inhibition of H835 but not H187. Nitrosamine-treated hamsters also demonstrate pulmonary neuroendocrine cell apoptosis in situ during the same time period as expression of the endogenous HGFL/ MSP gene, immediately preceding the spontaneous regression of neuroendocrine cell hyperplasia. These observations suggest that HGFL/MSP might regulate neuroendocrine cell survival during preneoplastic lung injury, which could influence the ultimate tumor cell phenotype.

Animals↗
PubMed1997

High risk of breast carcinoma after irradiation of young women with Hodgkin's disease.

BACKGROUND: Treatment-associated second neoplasms have emerged as a major threat to the continued survival of patients cured of Hodgkin's disease. In this study, the authors investigated the risk of breast carcinoma in an irradiated Hodgkin's disease population. METHODS: One hundred and eleven women younger than 60 years presenting between 1964 and 1984 with Stage I and II Hodgkin's disease who received mantle irradiation were retrospectively analyzed and compared with an age specific population. Median follow-up was 18 years (range, 10-30 years), and the median age at initiation of therapy was 24 years. Kaplan-Meier actuarial risks, relative risks (RRs) (the ratio of the observed to the expected cases) with 95% confidence intervals (CIs), and the log rank test for trends were calculated. RESULTS: Fourteen women developed breast carcinoma: 8 of 33 patients younger than 20 years at the time of irradiation, 5 of 48 patients age 20 to 29 years, and 1 of 30 patients age 30 years or older. Actuarial calculation predicted a 34.0% (CI, 14.2-53.8) risk of breast carcinoma at 25 years after therapy for the youngest group, 22.3% (CI, 4.1-40.5) for the group of intermediate age, and 3.5% (CI, 0-10.1) for the oldest group. The RR of breast carcinoma was 56 (CI, 23.3-107) for those 19 years or younger at the time of treatment, 7.0 (CI, 2.3-16.4) for those age 20-29 years, and 0.9 (CI, 0-5.3) for those 30 years and older. Excluding 1 patient who was age 38 years at the time of irradiation, the remaining 13 breast carcinomas were tightly clustered in women irradiated between the ages of 14 through 25, and were detected in years 11 through 25 after treatment, with 7 occurring in years 15 through 18. CONCLUSIONS: Women younger than 30 years, particularly those younger than 20 years, who have received mantle irradiation for Hodgkin's disease require meticulous follow-up for breast carcinoma. The high incidence of breast carcinoma in this patient population should be considered when making treatment decisions in young women with early stage Hodgkin's disease.

Adolescent↗
PubMed1997

Appendiceal carcinoma: patterns of failure following surgery and implications for adjuvant therapy.

BACKGROUND AND OBJECTIVES: Primary adenocarcinoma of the appendix is rare, which makes an understanding of its natural history difficult. To date, it is treated predominantly with surgery alone. This review aims to elucidate the patterns of failure and treatment outcomes when adjuvant treatment is given after primary surgical resection. METHODS: Twenty-three patients were treated with either surgery alone, or with surgery and adjuvant radiation +/- chemotherapy. A review of the clinical course of these patients was undertaken with an analysis of the local control, distant failure, disease-free survival, and overall survival. RESULTS: Most patients presented with local invasion or metastatic disease often involving the peritoneum. Overall survival was 32%, similar to the results of other studies. Analysis of patients with locally advanced disease showed improvement in overall survival and local control with postoperative radiation therapy compared to surgery alone. CONCLUSIONS: Adenocarcinoma of the appendix is a rare disease that presents most often in an advanced stage. It has been shown by others that a right hemicolectomy provides the best outcome with respect to surgical procedure. Postoperative irradiation appears to provide a benefit for both local control and overall survival.

Adenocarcinoma↗
PubMed1997

Intraoperative irradiation: current and future status.

Intraoperative radiation therapy (IORT) in its broadest sense refers to the delivery of irradiation at the time of an operation. This article will discusses the rationale for and results of both intraoperative electron radiation therapy and intraoperative high dose rate brachytherapy when used in conjunction with surgical exploration and resection and external beam radiation therapy and chemotherapy. Both IORT methods evolved with similar philosophies as an attempt to achieve higher effective doses of irradiation while dose limiting structures are surgically displaced.

Brachytherapy↗
PubMed1996

CA 19-9 is an index of response to neoadjunctive chemoradiation therapy in pancreatic cancer.

PURPOSE: This study examines the changes of serum levels of CA 19-9 in patients with pancreatic cancer following neoadjuvant irradiation and chemotherapy to define the potential role of this tumor marker in preoperative management of these patients. MATERIALS AND METHODS: Serum CA 19-9 levels were measured in 42 patients before receiving external beam irradiation with concurrent 5-fluorouracil in preparation for laparotomy and Whipple procedure or intraoperative irradiation (IORT). The CA 19-9 levels were determined again after irradiation, and changes were correlated with findings of restaging computed tomography (CT) scan and laparotomy. RESULTS: Following preoperative irradiation, 10 patients (24%) experienced an increase in CA 19-9 levels whereas 29 patients (69%) showed a decrease in CA 19-9. There was no change in the CA 19-9 levels of 3 patients (7%) after treatment. Of the 10 patients with increased CA 19-9 levels after irradiation, 9 (90%) had developed distant metastases or local tumor progression as determined by restaging CT scan or at laparotomy. In contrast, only 6 of 29 patients (21%) with declining CA 19-9 levels after irradiation demonstrated metastases or local tumor progression on restaging CT scan or at laparotomy. The correlation of CA 19-9 increase or decrease with disease progression or control, respectively, was statistically significant (P = 0.009). CONCLUSIONS: Serum CA 19-9 levels may rise or fall during neoadjuvant therapy. A rising CA 19-9 reliably indicates cancer progression while a falling CA 19-9 connotes disease control in the majority of patients. In developing strategies for application of neoadjuvant therapy for pancreatic cancer, monitoring of CA 19-9 appears most useful for the identification of patients who manifest progressive tumor growth and metastasis in spite of this treatment.

Adult↗
PubMed1996

Organ preservation in anal and rectal cancers.

For the past 10 to 15 years, radiation therapy and chemotherapy have played an increasingly important role in the treatment of various gastrointestinal malignancies, most prominently in anal and rectal cancer. Critical issues in the care of patients with anal and rectal cancer include not only local control and survival but organ preservation as well. For patients with carcinoma of the anal canal, external-beam irradiation with 5-fluorouracil and chemotherapy with mitomycin C have replaced surgery as primary therapy. Current studies are optimizing this therapy. In contrast, the management of distal rectal cancer is in evolution. Although the abdominoperineal resection has been long regarded as the definitive treatment of distal rectal cancer, it is associated with substantial morbidity (loss of anorectal function with a permanent colostomy and a high incidence of sexual and genitourinary dysfunction). As an alternative, treatment programs utilizing sphincter-preserving procedures with radiation therapy and chemotherapy are under active investigation. In selected patients, these strategies appear promising, and there have been reports of satisfactory local control and survival, as well as preservation of sphincter integrity.

Anus Neoplasms↗
PubMed1995

Rectal cancer: the influence of tumor proliferation on response to preoperative irradiation.

PURPOSE: Regression of rectal carcinoma after preoperative irradiation is variable, likely reflecting differences in the physical and biologic properties of these tumors. This study examines the association between the pathologic response of rectal cancer after irradiation and its pretreatment proliferative state as assayed by the activity of the proliferative dependent antigens (Ki-67, PCNA) and mitotic counts. METHODS AND MATERIALS: One hundred and twenty-two patients with locally advanced rectal cancer received preoperative irradiation followed by surgery. Pretreatment tumor biopsies were scored for the extent of Ki-67 and PCNA immunostaining and the number of mitoses per 10 high-powered fields. Postirradiation surgical specimens were examined for extent of residual disease. RESULTS: The tumors of 38 of 122 patients (31%) exhibited marked pathologic downstaging (no residual tumor or cancer confined to the rectal wall) after preoperative irradiation. Two features were associated with the likelihood of marked pathologic regression after preoperative irradiation: tumor proliferative activity and lesion size. When stratified by lesion size, marked tumor regression occurred most frequently in smaller tumors with high Ki-67, PCNA, and mitotic activity compared to larger tumors with lower Ki-67, PCNA, and mitotic activity. Intermediate downstaging rates were seen for small or large tumors with moderate Ki-67, PCNA, and mitotic activity. CONCLUSION: Tumor Ki-67, PCNA, and mitotic activity predicts the likelihood of response to irradiation, which may aid in formulating treatment policies for patients with rectal cancer.

Adult↗
PubMed1995

Intraoperative radiation therapy for locally advanced recurrent rectal or rectosigmoid cancer.

Recurrent rectal or rectosigmoid cancer is a difficult therapeutic problem. A treatment program of external beam irradiation, surgery, and intraoperative irradiation has been used for 41 patients. The 5-year actuarial local control and disease-free survival of all 41 patients was 30% and 16%, respectively. Subset analysis demonstrated differences in outcome by extent of surgical resection. The 5-year actuarial local control and disease-free survival of 27 patients undergoing complete resection was 47% and 21%, respectively. By contrast, the outcome of 14 patients undergoing partial resection was poor, with a 5-year actuarial local control and survival of 21% and 7%, respectively. Late complications included soft tissue or peripheral nerve injury, with many of these resolving within 4-18 months. Local control and disease-free survival rates are favorable in comparison with the results achieved by aggressive surgery. Patients who achieve a gross total resection at intraoperative irradiation have a markedly better prognosis than that of patients with residual gross disease.

Adenocarcinoma↗
PubMed1995

Tumor proliferation in rectal cancer following preoperative irradiation.

PURPOSE: This study examines the effect of preoperative irradiation on tumor proliferation in rectal cancer. PATIENTS AND METHODS: One hundred twenty-two patients with locally advanced rectal cancer received 45 to 50 Gy of preoperative irradiation followed by surgery. Pretreatment tumor biopsies and postirradiation surgical specimens were scored for proliferative activity by assaying the extent of Ki-67 and proliferating-cell nuclear antigen (PCNA) immunostaining and the number of mitoses per 10 high-power fields (hpf). Preirradiation and postirradiation proliferative activity was determined and correlated to clinical outcome. RESULTS: There was an overall reduction in the tumor proliferative activity of rectal cancer after irradiation compared with its preirradiation state. Decreases in the activity of all three markers of tumor proliferation (Ki-67 and PCNA immunostaining, and mitotic counts) were observed in irradiated tumors compared with pretreatment biopsies. Postirradiation tumor proliferative activity was associated with pathologic tumor stage. A high level of proliferative activity was observed in tumors downstaged to the rectal wall (T1-2) compared with tumors that retained transmural penetration (T3-4). Multivariate analysis indicated that postirradiation proliferative activity and stage were independently associated with survival following surgery. Patients with tumors that exhibited elevated proliferative activity postirradiation had improved survival compared with patients with tumors that showed less proliferative activity. CONCLUSION: Moderate- to high-dose preoperative irradiation decreases both the tumor size and proliferative activity of rectal cancers. Elevated postirradiation tumor proliferative activity correlates strongly with improved survival. This may aid in identifying high-risk patients following preoperative irradiation and surgery.

Adult↗
PubMed1995

Histochemical characterization of non-neuroendocrine tumors and neuroendocrine cell hyperplasia induced in hamster lung by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone with or without hyperoxia.

Lung tumors induced by 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanone (NNK) with or without hyperoxia have frequent K-ras mutations but only rare p53 mutations, suggesting that this may be a model for non-small cell lung cancers. The goals of the present study were (1) to characterize the histopathology of lung tumors induced in hamsters by NNK with or without O2 and (2) as a corollary, to quantitate the pulmonary neuroendocrine cell hyperplasia in the different treatment groups early and late in the treatment period. Lung tumors induced by NNK with or without O2 were 71% adenomas, 22% adenocarcinomas, approximately 4% bronchoalveolar carcinomas, and approximately 4% squamous/adenosquamous carcinomas. One-half of all tumors were positive for the Clara cell antigen CC10 and 21% of NNK-induced tumors were mucin positive, compared with 2% of NNK/O2-induced tumors (P = 0.003). Immunostaining for PGP9.5 was positive in 5% of tumors induced by NNK alone, but in none of NNK/O2-induced tumors (P = 0.024). Abundant proliferating cell nuclear antigen occurred in 55% of NNK-induced tumors, compared with 19% of NNK/O2-induced tumors (P = 0.009). These data indicate that NNK with or without O2 induces non-neuroendocrine lung tumors. Hyperoxia appears to inhibit cell proliferation and suppress mucinous and partial neuroendocrine differentiation in some of these tumors.

Animals↗
PubMed1994

Selection factors for local excision or abdominoperineal resection of early stage rectal cancer.

BACKGROUND: This study reviews the experience of patients with early stage rectal cancer managed by local excision or abdominoperineal resection to clarify the relative indications and results of these two approaches. METHODS: From 1962 to 1991, 125 patients with T1 and T2 rectal cancer underwent local excision (56 patients) or abdominoperineal resection (69 patients). Outcome was analyzed by stage, treatment, and pathologic features of tumor grade and vessel involvement. RESULTS: The 5-year actuarial recurrence-free survival and local control was 87% and 96%, respectively, for 28 patients undergoing local excision with favorable histologic features (well or moderately well differentiated histologic findings without venous/lymph vessel involvement). These results were 57% and 68% for 28 patients with unfavorable histologic features (poorly differentiated histology and/or venous/lymph vessel involvement). For patients undergoing abdominoperineal resection, the 5-year actuarial recurrence-free survival and local control of 49 patients with favorable histologic features was 91% and 91%, respectively. These results were 79% and 89%, respectively, for patients with poorly differentiated histology or venous/lymph vessel involvement. CONCLUSIONS: For patients with T1 and T2 tumors having favorable histologic features, a satisfactory survival and local control was achieved for patients undergoing local excision or abdominoperineal resection. In contrast, patients with T1 and T2 tumors having poorly differentiated histologic features and/or venous/lymph vessel involvement undergoing local excision or abdominoperineal resection appeared to have decreased rates of survival and of local control. For these patients, radical resection combined with pelvic irradiation and 5-fluorouracil-based chemotherapy should be investigated.

Abdomen↗
PubMed1994

Radical radiation therapy in the management of prostatic adenocarcinoma: the initial prostate specific antigen value as a predictor of treatment outcome.

We studied 161 prostate cancer patients treated by radical irradiation alone without endocrine therapy in whom pretreatment and posttreatment prostate specific antigen (PSA) values were measured, and who had a minimum followup of 2 years. Outcome was analyzed in an actuarial fashion using clinical disease-free survival and biochemical disease-free survival (freedom from an increasing PSA level or a PSA level of greater than 1.0 ng./ml. 2 years following irradiation) as end points. Of the patients 54% achieved a post-irradiation nadir value in the range 0 to 1.0 ng./ml. and 29% had a nadir value that was undetectably low (less than 0.5 ng./ml.). The likelihood of achieving these values was greater among patients with early stage than locally advanced tumors. For all T stages the likelihood of being disease-free at 4 years was substantially and significantly lower when PSA was used as an end point than when clinical evaluation alone was used: stages T1 and T2 (85 patients) 41% versus 71%, and stages T3 and T4 (76 patients) 15% versus 61%. For the whole group at 4 years clinical control was 67% but biochemical control was only 26% (p < 0.05). The likelihood of being free of biochemical evidence of persistent disease at 4 years was a function of the initial PSA value (PSA less than 4.0 in 81% of the cases, 4.1 to 10.0 in 43%, 10.1 to 20.0 in 31%, 20.1 to 50.0 in 6% and greater than 50.0 in 0%). For stages T1 and T2 cancer patients with an initial PSA level of less than 15 ng./ml. (67% of all early stage cases) this value was 65% and it was even higher (73%) when poorly differentiated tumors were excluded. When the initial PSA level for stages T1 and T2 tumors was greater than 15 ng./ml. the projected 4-year rate of freedom from biochemical failure was only 7%. For stages T3 and T4 cancer patients the corresponding figures were 39% for those with an initial PSA level of less than 15 ng./ml. and 0% for those with an initial PSA level of greater than 15 ng./ml. The prognostic power of the initial PSA level was independent of stage, grade, patient age and prior transurethral resection of the prostate in a multivariate analysis. An initial serum PSA level of more than 15 ng./ml. is, therefore, a powerful predictor of probable failure with conventional radiation therapy. Serum PSA monitoring is a sensitive detector of early relapse.(ABSTRACT TRUNCATED AT 400 WORDS)

Actuarial Analysis↗