Biomedical subjects

Jennifer Bacik

Publications and source records attributed to Jennifer Bacik.

7 recordsLinked to original sources

PubMed2003

Cluster analysis of p53 and Ki67 expression, apoptosis, alpha-fetoprotein, and human chorionic gonadotrophin indicates a favorable prognostic subgroup within the embryonal carcinoma germ cell tumor.

PURPOSE: The prognostic information provided by alpha-fetoprotein and human chorionic gonadotrophin in the management of germ cell tumor (GCT) patients is a biochemical reflection of tumor differentiation. Ki67, p53, and apoptosis have been found to be related to proliferation (Ki67), cell death (p53, apoptosis), and possibly differentiation chemoresistance (p53). We sought to determine whether simultaneous expression of one or more of these markers could identify clinically relevant subgroups of patients with nonseminomatous GCT (NSGCT). PATIENTS AND METHODS: These five marker values were obtained for 95 previously untreated patients with embryonal carcinoma with or without other germ cell components. A multivariate cluster analysis was performed to identify patients with similar marker patterns. RESULTS: One prominent cluster (n = 37; 36 testis retroperitoneum), consisting of 26 (70%) good-risk (GR), nine (24%) intermediate-risk (IR), and two (6%) poor-risk (PR) patients, as defined by the International Germ Cell Consensus Cancer Group (IGCCCG), was observed. The 5-year survival of the prominent cluster (with 30% IR/PR patients) was 94% (95% confidence interval [CI], 86% to 100%), which is comparable to the 91% (95% CI, 89% to 93%) 5-year survival of the IGCCCG GR patients. IGCCCG risk status (P =.005) and cluster affiliation (P =.04) were independent predictors of outcome with hazard ratios of 5.0 (95% CI, 1.6 to 15.4) and 4.6 (95% CI, 1.04 to 20.1), respectively. CONCLUSION: These results suggest that there is a subgroup of NSGCT patients with embryonal carcinoma (with or without other histologies) with a specific tumor biology profile (high Ki67, low apoptosis, and low p53) whose survival is better than that of the overall patient group. The unexpectedly good outcome for the prominent cluster and independent-risk status suggest that subgroups of GCT reflecting different abilities to respond to treatment exist within IGCCCG prognostic categories.

Apoptosis↗

PubMed2003

Methods for categorizing a prognostic variable in a multivariable setting.

The literature is filled with examples of categorization of a continuous prognostic variable in a univariable setting followed by the addition of this categorical variable to an existing multivariable model. Typically, an "optimal" cutpoint for a new prognostic variable is obtained through a systematic search relating the variable to the outcome in an univariable manner. The corresponding categorical variable is then fitted in a multivariable model along with other already established prognostic covariates to assess the additional value of the new variable. This prompts the question whether the cutpoint search should have been performed in the same multivariable setting where it will ultimately be used. In this paper, we extend the univariable cutpoint search methods (split-sample approach and two-fold cross-validation approach) to the multivariable setting using -2 x log-likelihood statistic as the correlative measure. A Monte Carlo simulation study demonstrates that both methods are more efficient in detecting the true cutpoint and in estimating the effect size under the multivariable setting as opposed to the univariable setting. The cross-validation method performs better than the split-sample method in univariable as well as multivariable scenarios. For the cross-validation method in the multivariable setting, there is still a substantial loss of power when a cutpoint model is used in cases where there is a continuous relationship between the covariate and the outcome. An example is provided to illustrate the value of the multivariable cross-validation approach.

Humans↗

PubMed2002

Treatment outcome and survival associated with metastatic renal cell carcinoma of non-clear-cell histology.

PURPOSE: To define outcome data for patients with metastatic renal cell carcinoma (RCC) with histology other than clear-cell type, including collecting duct (or medullary carcinoma), papillary, chromophobe, and unclassified histologies. PATIENTS AND METHODS: Sixty-four patients with metastatic non-clear-cell RCC histology were the subjects of this retrospective review. Included in the analysis were 22 (8%) of 286 patients from a clinical trials database, 19 of 1,166 patients from a surgery database, and 23 of 357 patients from a pathology database. RESULTS: The prevalent histology was collecting duct, present in 26 (41%) patients. The number of patients with chromophobe and papillary histologies was 12 (19%) and 18 (28%), respectively. Eight (12%) of the patients had tumors that could not be classified for specific tumor histology. Among the 43 patients treated with 86 systemic therapies, including 37 cytokine therapies, two patients (5%) were observed to have a partial response. The median overall survival time was 9.4 months (95% confidence interval, 8 to 14 months). The survival was longer for patients with chromophobe tumors compared with collecting duct or papillary histology, and this group included four patients with survival of greater than 3 years. CONCLUSION: RCC consists of a heterogeneous group of tumors including clear-cell, papillary, chromophobe, collecting duct, and unclassified cell types. Non-clear-cell histologies constitute less than 10% of patients in general populations of patients with advanced RCC treated on clinical trials. Metastatic non-clear-cell RCC is characterized by a resistance to systemic therapy and poor survival, with the survival for patients with chromophobe tumors longer than that for patients with metastatic collecting duct or papillary RCC. Treatment with novel agents on clinical trials is warranted.

Adolescent↗

PubMed2002

Interferon-alfa as a comparative treatment for clinical trials of new therapies against advanced renal cell carcinoma.

PURPOSE: To define outcome data and prognostic criteria for patients with metastatic renal cell carcinoma (RCC) treated with interferon-alfa as initial systemic therapy. The data can be applied to design and interpretation of clinical trials of new agents and treatment programs against this refractory malignancy. PATIENTS AND METHODS: Four hundred sixty-three patients with advanced RCC administered interferon-alpha as first-line systemic therapy on six prospective clinical trials were the subjects of this retrospective analysis. Three risk categories for predicting survival were identified on the basis of five pretreatment clinical features by a stratified Cox proportional hazards model. RESULTS: The median overall survival time was 13 months. The median time to progression was 4.7 months. Five variables were used as risk factors for short survival: low Karnofsky performance status, high lactate dehydrogenase, low serum hemoglobin, high corrected serum calcium, and time from initial RCC diagnosis to start of interferon-alpha therapy of less than one year. Each patient was assigned to one of three risk groups: those with zero risk factors (favorable risk), those with one or two (intermediate risk), and those with three or more (poor risk). The median time to death of patients deemed favorable risk was 30 months. Median survival time in the intermediate-risk group was 14 months. In contrast, the poor-risk group had a median survival time of 5 months. CONCLUSION: Progression-free and overall survival with interferon-alpha treatment can be compared with new therapies in phase II and III clinical investigations. The prognostic model is suitable for risk stratification of phase III trials using interferon-alpha as the comparative treatment arm.

Adult↗

PubMed2002

Salvage chemotherapy for patients with advanced pure seminoma.

PURPOSE: We describe the response to conventional or high-dose salvage chemotherapy in patients with advanced seminoma who experience disease progression after receiving first-line platinum-based treatment. PATIENTS AND METHODS: Twenty-seven patients with progressive, advanced, pure seminoma were treated with salvage chemotherapy. Fifteen patients were treated with conventional-dose cisplatin-and-ifosfamide combination chemotherapy. Twelve patients were treated with high-dose chemotherapy followed by autologous stem-cell rescue. RESULTS: Fifteen patients (56%) achieved a complete response (CR), nine achieved CR with a conventional-dose cisplatin and ifosfamide program, and six experienced CR after high-dose chemotherapy. Fourteen patients (52%) are alive and disease-free, with 13 (48%) continuously disease-free at a median follow-up of 72 months. Twelve (57%) of 21 patients whose pretreatment tumors were studied morphologically were found to have seminoma with atypia. Eight patients underwent resection after salvage chemotherapy; six with histologic findings of necrotic debris/fibrosis alone are alive and disease-free at last follow-up. Both patients with viable seminoma found at surgery died of disease. CONCLUSION: Most patients with advanced seminoma are cured with standard first-line programs of cisplatin and etoposide with or without bleomycin. A small minority of patients with pure seminoma have resistant tumors and require salvage chemotherapy. In this setting, approximately 50% of patients with recurrent pure seminoma achieve durable CR with conventional or high-dose salvage chemotherapy. Identification of biologic markers to predict clinical outcome and an enhanced understanding of the basic biologic features of seminoma may lead to improvements in the management of this disease.

Adult↗

PubMed2002

Phase II trial of thalidomide for patients with advanced renal cell carcinoma.

PURPOSE: To assess efficacy and toxicity of thalidomide in patients with advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: Twenty-six patients with RCC were treated with thalidomide at a starting dose of 200 mg daily. Thalidomide was increased by 200 mg every 2 weeks until a maximum dose of 800 mg or prohibitive toxicity was reached. Fifteen patients had prior nephrectomy, 11 patients had no prior systemic therapy, and 15 had received one prior systemic regimen. RESULTS: A maximum dose of 800 mg, 600 mg, 400 mg, and 200 mg was reached in five, 10, eight, and three patients, respectively. Grade 2 and 3 dyspnea occurred in four and three patients, respectively. Grade 2 and 3 neurologic toxicity was observed in five and two patients, respectively. Of the 25 assessable patients, the best response was stable disease in 16 (95% confidence interval [CI], 43% to 82%) patients. The 6-month progression-free survival rate was 32% (95% CI, 14% to 50%). Three patients achieved prolonged stable disease of 16, 16+, and 18+ months, including two patients who were refractory to previous cytokine therapy. Fifty-seven percent were alive at 1 year (95% CI, 37% to 76%). CONCLUSION: This trial does not support the routine use of thalidomide to induce partial response for metastatic RCC. Because disease stabilization occurs as a part of the natural history of metastatic RCC, the potential effect of thalidomide on progression-free and overall survival for patients with advanced RCC is being addressed in a randomized phase III trial. New immunomodulatory analogs of thalidomide that have shown potentially greater antitumor effects in preclinical models warrant study in metastatic RCC.

Adult↗

PubMed2002

Testicular seminoma: a clinicopathologic and immunohistochemical study of 105 cases with special reference to seminomas with atypical features.

In spite of the high curability rates, rare cases of testicular seminoma behave in an unexpectedly aggressive manner. No effective markers are currently available that can predict such uncommon behavior. We studied 105 cases of testicular seminoma on whom the primary resection was performed at the Memorial Sloan-Kettering Cancer Center, New York, to investigate any relationship between morphology, immunohistochemical features, and clinical/pathological stages. Fifty-nine percent of the cases presented with pT stage 1 and 74 percent with American Joint Committee on Cancer (AJCC) stage I. In univariate analysis, tumor size, mitotic count, and presence of necrosis showed significant associations with pT stage (p = 0.0001, 0.0001, and 0.04, respectively), and the presence of vascular invasion (p = 0.0001, 0.0001, and 0.02, respectively). In multivariate analysis, both the tumor size and mitotic counts were independent predictors of pT stage (p = 0.0004 and 0.0001) and vascular invasion (p = 0.0004 and 0.0001). When tumors were separated on the basis of architectural and/or cytological atypia into "usual seminomas" and "seminomas with atypia", these were significantly associated with AJCC stage (p = 0.02), and c-kit protein (p = 0.0005) and CD30 expression (p = 0.02). In addition, "seminomas with atypia" also tended to show a higher proliferation activity as judged by Ki67 reactivity (p = 0.06), as well as express the marker of epithelial differentiation, Cam 5.2 (p = 0.09). In summary, we find that the morphologic features in testicular seminomas are associated with factors of clinical relevance. Also, "seminomas with atypia" differ from "usual seminomas" morphologically, present at a higher AJCC stage, and possibly represent an early step in transformation of seminomas toward a more aggressive phenotype. While not proposing a new entity, we suggest that when these atypical features are encountered in an otherwise classical seminoma, investigations must be performed to exclude an early carcinomatous differentiation or even earlier changes toward such a differentiation, such as lack of c-kit protein expression.

Adult↗