Biomedical subjects

M Mazumdar

Publications and source records attributed to M Mazumdar.

At least 37 records · Page 2Linked to original sources

PubMed2000

Whole-Body FDG-PET in Patients with Recurrent Colorectal Carcinoma. A Comparative Study with CT.

Purpose: To assess the clinical accuracy of whole-body 2-[F-18]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in the diagnosis of recurrent colorectal carcinoma in comparison to conventional computed tomography (CT).Materials and methods: Forty patients with suspected recurrent colorectal carcinoma based on either progressive serial carcinoemrbyonic antigen (CEA) serum elevation or positive/equivocal CT findings underwent whole-body FDG-PET. PET results were compared with those of CT and correlated to the final histopathological and clinical findings.Results: A final diagnosis was obtained at 93 sites in 35 patients by histology and in 5 patients by clinical follow up of at least 6 months. Of the 93 sites, 53 were determined to be malignant and 40 benign. FDG-PET evaluated on a 5-point scale (0-4) showed a positive and negative predictive value in the range of 96-98% and 83-93% respectively as the threshold for positivity was moved from 0 through 3. By comparison, CT, also evaluated on a 5-point scale showed a positive and negative predictive value in the range of 75-88% and 67-71% respectively. The area under the fitted receiver operating characteristic curve for PET: A(PET) = 0.96 +/- 0.02 was significantly greater (P < 0.001) than that observed for CT: A(CT) = 0.77 +/- 0.06. The distribution of maximum standardized uptake value (SUVmax) showed that all negative lesions have SUVmax below 5.0 whereas 75% of positive lesions were above 5.0 pointing to the fact that disease positivity is more likely in lesions with high SUV values.Conclusion: The results of this study confirm that whole-body FDG-PET is more accurate than conventional CT in the staging of patients with suspected recurrent colorectal carcinoma.

Journal Article↗

PubMed2000

Phase II trial of pyrazoloacridine as second-line therapy for patients with unresectable or metastatic transitional cell carcinoma.

PURPOSE: A phase II trial of pyrazoloacridine (PZA) was conducted to assess its activity and toxicity in patients with advanced transitional cell carcinoma (TCC) refractory to or progressing after one prior cisplatin-, carboplatin- or paclitaxel- based regimen. PATIENTS AND METHODS: PZA at a dose of 750 mg/m2 was administered to 14 patients as a three-hour intravenous infusion on day 1 every 21 days. Premedication consisted of lorazepam 0.5-1.0 mg prior to each cycle to alleviate central nervous system toxicity. Reduction of subsequent doses was made for hematologic or central nervous system toxicity. RESULTS: Among fourteen patients evaluable for response, no responses were observed (0% response rate; 95% confidence interval 0% to 23%). The median duration of survival for all patients was 9 months with a median follow-up of 8.5 months. Toxicity to PZA included grade 3 or 4 neutropenia in 8/14 (57%) and grade 3 or 4 thrombocytopenia in 2/14 (14%). Non-hematologic toxicity was mild. CONCLUSIONS: PZA at this dose and schedule does not have significant single-agent activity in patients with TCC who have failed one prior regimen.

Acridines↗

PubMed2000

Analysis of the insertion/deletion polymorphism of the human angiotensin converting enzyme (ACE) gene in patients with renal cancer.

The angiotensin I-converting enzyme (ACE) contains an insertion/deletion (I/D) polymorphism, with the DD genotype associated with benign renal diseases. The distribution frequencies of the D and I alleles, and the DD, DI and II genotypes were determined in DNA extracted from kidney tissues of 58 renal cancer patients. The observed frequencies in patients who develop renal cancer was not significantly different than the normal population.

Adult↗

PubMed2000

Paclitaxel, ifosfamide, and cisplatin second-line therapy for patients with relapsed testicular germ cell cancer.

PURPOSE: To evaluate the dose, toxicity, and efficacy of paclitaxel in combination with ifosfamide and cisplatin as salvage therapy for patients with relapsed testicular germ cell tumors (GCTs). PATIENTS AND METHODS: Thirty patients with previously treated GCTs were treated with paclitaxel and ifosfamide plus cisplatin (TIP) as second-line therapy. All had favorable prognostic features for response (testis primary tumor site and prior complete response to first-line chemotherapy program). Four cycles of paclitaxel, ifosfamide 5 g/m(2), and cisplatin 100 mg/m(2) were given 21 days apart with granulocyte colony-stimulating factor support, followed by resection of radiographic residua. The dose of paclitaxel was increased among cohorts with dose levels of 175, 215, and 250 mg/m(2); the largest dose was selected for the phase II part of the trial. RESULTS: Twenty-three (77%) of 30 patients achieved a complete response to chemotherapy alone, and one patient achieved a durable partial response with normal tumor markers. Therefore, 24 (80%) achieved a favorable response. Eleven patients with normalized markers after chemotherapy underwent resection of residual tissue, with only necrosis found in 10 and mature teratoma in one. Two patients relapsed, and 22 (73%) of the favorable responses remain durable at a median follow-up duration of 33 months. Myelosuppression was the major toxicity, and two patients had grade 3 neurotoxicity. CONCLUSION: Four cycles of TIP was associated with a high proportion of patients who achieved a complete response, a lack of relapse, and relative tolerability as an ifosfamide-containing salvage regimen for testicular GCTs. The high durable complete response proportion emphasizes the importance of patient selection according to prognostic factors for a favorable outcome to conventional-dose salvage therapy.

Adult↗

PubMed2000

Phase III trial of interferon alfa-2a with or without 13-cis-retinoic acid for patients with advanced renal cell carcinoma.

PURPOSE: A randomized phase III trial was conducted to determine whether combination therapy with 13-cis-retinoic acid (13-CRA) plus interferon alfa-2a (IFNalpha2a) is superior to IFNalpha2a alone in patients with advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: Two hundred eighty-four patients were randomized to treatment with IFNalpha2a plus 13-CRA or treatment with IFNalpha2a alone. IFNalpha2a was given daily subcutaneously, starting at a dose of 3 million units (MU). The dose was escalated every 7 days from 3 to 9 MU (by increments of 3 MU), unless >/= grade 2 toxicity occurred, in which case dose escalation was stopped. Patients randomized to combination therapy were given oral 13-CRA 1 mg/kg/d plus IFNalpha2a. Quality of life (QOL) was assessed. RESULTS: Complete or partial responses were achieved by 12% of patients treated with IFNalpha2a plus 13-CRA and 6% of patients treated with IFNalpha2a (P =.14). Median duration of response (complete and partial combined) in the group treated with the combination was 33 months (range, 9 to 50 months), versus 22 months (range, 5 to 38 months) for the second group (P =.03). Nineteen percent of patients treated with IFNalpha2a plus 13-CRA were progression-free at 24 months, compared with 10% of patients treated with IFNalpha2a alone (P =.05). Median survival time for all patients was 15 months, with no difference in survival between the two treatment arms (P =.26). QOL decreased during the first 8 weeks of treatment, and a partial recovery followed. Lower scores were associated with the combination therapy. CONCLUSION: Response proportion and survival did not improve significantly with the addition of 13-CRA to IFNalpha2a therapy in patients with advanced RCC. 13-CRA may lengthen response to IFNalpha2a therapy in patients with IFNalpha2a-sensitive tumors. Treatment, particularly the combination therapy, was associated with a decrease in QOL.

Administration, Oral↗

PubMed2000

Phase I evaluation of sequential doxorubicin gemcitabine then ifosfamide paclitaxel cisplatin for patients with unresectable or metastatic transitional-cell carcinoma of the urothelial tract.

PURPOSE: This phase I trial sought to evaluate the toxicity of and determine the maximum-tolerated dose (MTD) for the two-drug regimen doxorubicin and gemcitabine (AG) followed by the three-drug regimen of ifosfamide, paclitaxel, and cisplatin (ITP) in patients with unresectable or metastatic transitional-cell carcinoma. PATIENTS AND METHODS: Patients received AG every other week for six cycles followed by ITP every 3 weeks for four cycles. Five AG dose levels were investigated, up to doxorubicin 50 mg/m(2) and gemcitabine 2, 000 mg/m(2), to determine the MTD of the regimen. The dose and schedule of ITP were constant: ifosfamide 1,500 mg/m(2) (days 1 to 3); paclitaxel 200 mg/m(2) (day 1); and cisplatin 70 mg/m(2) (day 1). Granulocyte colony-stimulating factor was given between all cycles of therapy. RESULTS: Fifteen patients enrolled onto this phase I trial. AG was well tolerated at all dose levels, with no grade 3 or 4 myelosuppression. Toxicity experienced with ITP included grade 3 and 4 granulocytopenia in four patients and grade 3 nausea/vomiting in three patients. No grade 3 and 4 neurotoxicity was observed. Eight of 14 assessable patients experienced a major response to AG, including five of six patients treated at the two highest AG dose levels. After completion of AG-ITP, nine of 14 assessable patients had a major response (three complete responses and six partial responses). CONCLUSION: AG is a well-tolerated and active regimen. Sequential chemotherapy with AG-ITP is also well tolerated, and phase II investigation at the highest dose level is ongoing.

Aged↗

PubMed2000

Sequential dose-intensive paclitaxel, ifosfamide, carboplatin, and etoposide salvage therapy for germ cell tumor patients.

PURPOSE: To evaluate the efficacy and toxicity of sequential, dose-intensified chemotherapy with paclitaxel/ifosfamide and carboplatin/etoposide administered plus peripheral blood-derived stem-cell (PBSC) support for patients with germ cell tumors (GCT) who have unfavorable prognostic features in response to conventional-dose salvage programs. Carboplatin was dose escalated by target area under the curve (AUC; in [milligrams per milliliter] x minutes) among patient cohorts, and pharmacokinetic studies were performed for comparison. PATIENTS AND METHODS: Thirty-seven previously treated patients who had cisplatin-resistant GCT and unfavorable prognostic features for response to conventional-dose salvage therapy were treated. Two cycles of paclitaxel 200 mg/m(2) plus ifosfamide 6 g/m(2) were given 2 weeks apart with leukapheresis, followed by three cycles of carboplatin plus etoposide given 14 to 21 days apart with reinfusion of PBSCs. The dose of etoposide was 1, 200 mg/m(2), and the carboplatin target AUC ranged among cohorts from 12 to 32 (mg/mL) x min. Pharmacokinetic studies of carboplatin were performed for comparison of target to measured AUC. RESULTS: Twenty-one patients (57%) achieved a complete response and an additional two patients (5%) achieved a partial response with normal tumor markers; therefore, 23 (62%) achieved a favorable response. Eight patients relapsed, and 15 (41%) of the favorable responses remained durable at a median follow-up of 30 months. Myelosuppression was the major toxicity; 58% of carboplatin/etoposide cycles were associated with hospitalization for nadir fever. The AUC of carboplatin measured in serum was lower than the target AUC; this may be related to underestimation of the glomerular filtration rate used in the dosing formula. CONCLUSION: Dose-intense therapy with sequential, accelerated chemotherapy of paclitaxel/ifosfamide and carboplatin/etoposide administered with PBSC support was relatively well tolerated. The durable complete response proportion was substantial in patients with unfavorable prognostic features for achieving durable complete response to conventional-dose salvage programs. Optimal dosing of carboplatin in the high-dose setting warrants further investigation.

Adolescent↗

PubMed2000

Effect of cytokine therapy on survival for patients with advanced renal cell carcinoma.

PURPOSE: To evaluate the relationship between treatment with cytokine therapy and survival, investigate the effect of nephrectomy on survival, and identify long-term survivors among a cohort of 670 patients with advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: A total of 670 patients with advanced RCC treated on 24 clinical trials of systemic chemotherapy or cytokine therapy were the subjects of this retrospective analysis. Treatment was categorized as cytokine (containing interferon alfa and/or interleukin-2) in 396 patients (59%) and as chemotherapy (cytotoxic or hormonal therapy) in 274 (41%). Among the 670 patients, those with survival times of greater than 5 years were identified as long-term survivors. RESULTS: Patients treated with cytokine therapy had a longer survival time than did those treated with chemotherapy, regardless of the year of treatment or risk category based on pretreatment features. The median survival times for favorable-, intermediate-, and poor-risk patients were 27, 12, and 6 months for those treated with cytokines and 15, 7, and 3 months for those treated with chemotherapy, respectively. The magnitude of difference in median survival was greater in the favorable- and intermediate-risk groups. The median survival time was less than 6 months in the poor-risk group for both treatment programs. Median survival time was 14 months among patients with prior nephrectomy plus time from diagnosis to treatment greater than 1 year versus 8 months among those with time from diagnosis to treatment less than 1 year, regardless of pretreatment nephrectomy status. Thirty patients (4.5%) among the 670 patients were identified as long-term survivors; 12 were free of disease after nephrectomy and treatment with interferon alfa, interleukin-2, or surgical resection of metastasis. CONCLUSION: The low proportion of patients with advanced RCC who achieve long-term survival emphasizes the need for clinical investigation to identify more effective therapy.

Adolescent↗

PubMed2000

Evaluation of drug delivery and survival impact of dose-intense relative to conventional-dose methotrexate, vinblastine, doxorubicin, and cisplatin chemotherapy in urothelial cancer.

The efficacy of dose-intense methotrexate, vinblastine, doxorubicin, and cisplatin (M-VAC) chemotherapy relative to conventional-dose M-VAC in patients with advanced transitional cell carcinoma is unknown. The outcomes of 33 patients on two successive protocols using dose-intense M-VAC with granulocyte colony-stimulating factor (G-CSF) support were compared with those of 129 patients treated with conventional-dose M-VAC to assess for an impact of dose-intense therapy on long-term survival. The mean relative dose intensity of chemotherapy delivered to the dose-intense cohort was 55% higher than that delivered to the conventional-dose cohort (p = 0.0001). However, no significant differences were observed with regard to response proportion (72% vs. 76%), median survival (13.3 vs. 16.7 months, p = 0.31), or 5-year survival (16% vs. 15%). Growth factor support enabled a statistically significant increase in the delivered dose intensity of M-VAC chemotherapy, but no survival advantage relative to conventional-dose M-VAC was observed.

Adult↗

PubMed1999

Phase II trial of intermediate dose methotrexate in combination with vinblastine, doxorubicin, and cisplatin in patients with unresectable or metastatic transitional cell carcinoma.

BACKGROUND: This study was undertaken to determine whether the use of intermediate dose methotrexate in combination with vinblastine, doxorubicin, and cisplatin as first-line therapy increases the proportion of major responders and overall survival in patients with unresectable or metastatic transitional cell carcinoma (TCC) of the urothelial tract. METHODS: Twenty-nine patients with histologically confirmed TCC received methotrexate at a dose of 1000 mg/m2 on Day 1 followed by leucovorin calcium rescue on Day 2 and vinblastine (3 mg/m2), doxorubicin (30 mg/m2), and cisplatin (70 mg/m2) (VAC) on Day 2. Therapy was recycled at 28-day intervals. RESULTS: Fourteen of 28 patients (50%; 95% confidence interval [CI], 31-69%) achieved a major response, including 6 pathologic or clinical complete responses (CR) and 8 partial responses (PR). Nine patients were rendered disease free after postchemotherapy surgical resection of residual disease (surgical CR), including five patients who had PR and four nonresponders to chemotherapy alone. Five of 18 patients with disease limited to lymph nodes attained CR, in contrast to only 1 of 10 patients with visceral metastatic disease. The median survival for the entire population was 13.6 months. CONCLUSIONS: The escalation of methotrexate to 1000 mg/m2 in combination with vinblastine, doxorubicin, and cisplatin did not result in a response proportion or median survival superior to that observed with standard dose M-VAC. As previously observed in a Phase II trial of M-VAC, only the attainment of CR was associated with prolongation of survival.

Adult↗

PubMed1999

Predicting slips and falls considering required and available friction.

This study investigated the relationship among measurements of friction, the biomechanics of gait, and actual slip and fall events. The goal was to develop a method for estimating the probability of slips and falls based on measurements of available friction and required friction. Five subjects wearing safety harnesses walked down a ramp at various angles with either a tile or carpeted surface under dry, wet or soapy conditions. Ramp angles of 0 degree, 10 degrees and 20 degrees were used to vary the shear and normal foot force requirements. The dynamic coefficient of friction (DCOF) of shoe, floor surface and contaminant interfaces was measured. Required friction was assessed by examining the foot forces during walking trials when no slips occurred. Slips with recoveries and slips resulting in falls were recorded and categorized using a force plate and high-speed video camera. These data were then incorporated into a logistic regression to model the probability of a slip or fall event occurring based on the difference between the COF required by the foot forces generated and the measured DCOF. The results showed that the number of slip and fall events increased as the difference between the required COF and the measured DCOF increased. The logistic regression model fit the data well, resulting in an estimate of the probability of a slip or fall event based on the difference between the measured and required friction. This type of model could be used in the future to evaluate slip resistance measurement devices under various environments and assist in the design of safer work environments.

Accidental Falls↗

PubMed1999

Long-term survival in metastatic transitional-cell carcinoma and prognostic factors predicting outcome of therapy.

PURPOSE: The variation in reported survival of patients with metastatic transitional-cell carcinoma (TCC) treated with systemic chemotherapy may be a consequence of pretreatment patient characteristics. We hypothesized that a prognostic factor-based model of survival among patients treated with methotrexate, vinblastine, doxorubicin, and cisplatin chemotherapy could account for such differences and help guide clinical trial design and interpretation. PATIENTS AND METHODS: A database of 203 patients with unresectable or metastatic TCC was retrospectively subjected to a multivariate regression analysis to determine which patient characteristics had independent prognostic significance for survival. Patients were assigned to three risk categories depending on the number of unfavorable characteristics. Patient selection in phase II studies was addressed by developing a table of expected median survival for patient cohorts that had varying proportions of patients from the three risk categories. RESULTS: Two factors had independent prognosis: Karnofsky performance status (KPS) less than 80% and visceral (lung, liver, or bone) metastasis. Median survival times for patients who had zero, one, or two risk factors were 33, 13.4, and 9.3 months, respectively (P =.0001). The median survival time of patient cohorts could vary from 9 to 26 months simply by altering the proportion of patients from different risk categories. CONCLUSION: The presence of baseline KPS less than 80% or visceral metastasis has an impact on survival. Reporting the proportion of patients with zero, one, and two risk factors will facilitate understanding of the relevance of the median survival in phase II trials. Phase III trials should stratify patients according to the number of risk factors to avoid imbalance in treatment arms.

Adult↗

PubMed1999

Survival and prognostic stratification of 670 patients with advanced renal cell carcinoma.

PURPOSE: To identify prognostic factors and a model predictive for survival in patients with metastatic renal-cell carcinoma (RCC). PATIENTS AND METHODS: The relationship between pretreatment clinical features and survival was studied in 670 patients with advanced RCC treated in 24 Memorial Sloan-Kettering Cancer Center clinical trials between 1975 and 1996. Clinical features were first examined univariately. A stepwise modeling approach based on Cox proportional hazards regression was then used to form a multivariate model. The predictive performance of the model was internally validated through a two-step nonparametric bootstrapping process. RESULTS: The median survival time was 10 months (95% confidence interval [CI], 9 to 11 months). Fifty-seven of 670 patients remain alive, and the median follow-up time for survivors was 33 months. Pretreatment features associated with a shorter survival in the multivariate analysis were low Karnofsky performance status (<80%), high serum lactate dehydrogenase (> 1.5 times upper limit of normal), low hemoglobin (< lower limit of normal), high "corrected" serum calcium (> 10 mg/dL), and absence of prior nephrectomy. These were used as risk factors to categorize patients into three different groups. The median time to death in the 25% of patients with zero risk factors (favorable-risk) was 20 months. Fifty-three percent of the patients had one or two risk factors (intermediate-risk), and the median survival time in this group was 10 months. Patients with three or more risk factors (poor-risk), who comprised 22% of the patients, had a median survival time of 4 months. CONCLUSIONS: Five prognostic factors for predicting survival were identified and used to categorize patients with metastatic RCC into three risk groups, for which the median survival times were separated by 6 months or more. These risk categories can be used in clinical trial design and interpretation and in patient management. The low long-term survival rate emphasizes the priority of clinical investigation to identify more effective therapy.

Adult↗

PubMed1999

Outcome of postchemotherapy surgery after treatment with methotrexate, vinblastine, doxorubicin, and cisplatin in patients with unresectable or metastatic transitional cell carcinoma.

PURPOSE: The role of postchemotherapy surgery for patients with metastatic transitional cell carcinoma (TCC) is controversial. We retrospectively analyzed our experience with patients who underwent postchemotherapy surgery after methotrexate, vinblastine, doxorubicin, and cisplatin (M-VAC) chemotherapy to assess an impact on long-term survival. PATIENTS AND METHODS: This report is based on the retrospective analysis of 203 patients with unresectable primary tumors or metastatic TCC, previously reported in five trials of M-VAC chemotherapy. Fifty patients underwent postchemotherapy surgery for suspected or known residual disease. Characteristics of patients selected for surgery, results of surgery, and the impact of surgery on survival were assessed. RESULTS: In 17 patients, no viable tumor was found at postchemotherapy surgery, pathologically confirming a complete response to chemotherapy. Three patients had unresectable residual TCC. In 30 patients, residual, viable TCC was completely resected, which resulted in a complete response to chemotherapy plus surgery. Ten (33%) of these 30 patients remained alive at 5 years, similar to results observed for patients who attained a complete response to chemotherapy alone (41%). Analysis by baseline extent of disease suggested that patients with unresectable primary tumors or with metastases restricted to lymph node sites were most likely to survive for 5 years. CONCLUSION: Postchemotherapy surgical resection of residual cancer may result in 5-year disease-free survival in some patients who would otherwise succumb to disease. Optimal candidates include patients whose prechemotherapy sites of disease are restricted to the primary or lymph node sites and who have a major response to chemotherapy.

Adult↗

PubMed1999

Up-regulation of retinoic acid receptor beta expression in renal cancers in vivo correlates with response to 13-cis-retinoic acid and interferon-alpha-2a.

Retinoic acid receptor-beta (RAR-beta) mRNA is not expressed by retinoid-resistant renal cancer cell lines but is present in retinoid-sensitive SK-RC-06 renal cancer cells and increases following incubation with retinoic acid (RA), suggesting that the antitumor action of RA is mediated through RAR-beta (A. D. Hoffman et al., Clin. Cancer Res., 2: 1077-1082, 2996). To determine whether RAR-beta expression correlates in vivo with major clinical response to patients with renal cell carcinoma (RCC) who were treated with retinoid-based therapy, we used in situ hybridization to analyze RAR-beta expression in tumor specimens obtained from patients who were treated on a clinical trial with 13-cis-RA and IFN-alpha. Thirty-three tissue specimens were analyzed (23 pretreatment and 10 on-treatment). mRNA expression was based on staining intensity, with scores within tumor cells ranging from 0 to 2, where a score of 0 indicated absence of staining, a score of 1 indicated weak staining, and a score of 2 indicated strong staining. RAR-beta expression was present in 22 of 23 (96%) pretreatment and 9 of 10 (90%) on-treatment specimens. Pretreatment levels of expression did not associate with the site of biopsy and did not predict for major clinical response to RA plus IFN-alpha therapy (two-sided Fisher's exact test, P = 0.826). However, an increase in the intensity of RAR-beta mRNA expression was detected in four of five (80%) patients who achieved a major response but in none of the five patients with progressive disease in whom sequential biopsies were available (two-sided Fisher's exact test, P = 0.048). These data show that RAR-beta transcripts increase in tumor cells of RCC patients who clinically respond to retinoid-based therapy. Retinoids that potently induce RAR-beta expression should be evaluated in the treatment of advanced RCC.

Biopsy↗

PubMed1998

Engineering a lever into the kinesin neck.

To probe for a lever arm action in the kinesin stepping mechanism, we engineered a rodlike extension piece into the tail of rat kinesin at various points close to the head-tail junction and measured its effects on the temperature dependence of velocity in microtubule gliding assays. The insert comprised two contiguous alpha-actinin triple-coil repeats and was predicted to fold into a stiff rodlike module about 11 nm long. The effects of this module were greater the closer it was placed to the head-tail junction. When inserted distal to the head-tail junction, at Asn401 in the dimeric K partial differential401GST, the insert had no effect. When inserted closer to the heads at Val376 into K partial differential376GST, the insert slowed progress below 22 degreesC but accelerated progress to approximately 125% of wild type above 22 degreesC. The most dramatic effect of the synthetic lever occurred when it was inserted very close to the head-neck junction, at Glu340 into the single-headed construct K partial differential340GST. This construct was immotile without the insert, but motile with it, at about 30% of the velocity of the dimeric control. The alpha-actinin module thus confers some gain-of-function when inserted close to the head-neck junction but not when placed distal to it. The data exclude the presence of a lever arm C-terminal to Val376 in the kinesin tail but suggest that a short-throw lever arm may be present, N-terminal to Val376 and contiguous with the head-neck junction at Ala339.

Actinin↗

PubMed1998

Teratoma with malignant transformation: diverse malignant histologies arising in men with germ cell tumors.

PURPOSE: Teratoma with malignant transformation refers to a form of germ cell tumor in which a somatic teratomatous component becomes morphologically malignant and develops aggressive growth. We evaluated the spectrum of histologies, chromosomal abnormalities and clinical outcome in patients with teratoma with malignant transformation. MATERIALS AND METHODS: We identified 46 patients with germ cell tumor meeting morphologic criteria for malignant transformation. Histology, disease extent and treatment were correlated with survival. Tumors in 12 patients were studied by conventional cytogenetics or molecular genetic techniques for the isochromosome 12p [i(12p)], a marker for germ cell tumor, as well as other chromosomal abnormalities. RESULTS: The site of first detection of malignant transformation occurred in the primary tumor of 21 cases (44%), at a metastatic site in 20 (43%) and in both sites in 5 (10%). Sarcoma was the most frequent histology, identified in 29 patients (63%) with rhabdomyosarcoma the most common subtype. Seventeen tumors (37%) contained a solid tumor histology other than sarcoma, with adenocarcinoma and primitive neuroectodermal tumor as the most common histologies. Four patients with mediastinal germ cell tumor containing sarcoma also had hematological malignancies, including a focus of nonHodgkin's lymphoma in the mediastinal primary tumor (1) and nonlymphocytic leukemia in spleen or bone marrow (3). Patients who had teratoma with malignant transformation components confined to the testis or retroperitoneum completely resected experienced a longer survival than those with distant metastases or incompletely resected tumors (p = 0.003). Chromosomal abnormalities associated with germ cell tumor (i[12p]) were identified in 11 of 12 tumors containing adenocarcinoma, primitive neuroectodermal tumor, sarcoma and leukemia. In addition to i (12p), chromosomal rearrangements characteristic of the transformed histology were detected in 4 tumors. CONCLUSIONS: A variety of nongerm cell histologies, including sarcoma, adenocarcinoma, primitive neuroectodermal tumor and leukemia, may occur in association with germ cell tumor. Chromosomal abnormalities in these tumors include i (12p), reflecting germ cell tumor clonality, as well as chromosomal abnormalities associated with the transformed histology. These tumors do not respond like germ cell tumor to cisplatin-containing chemotherapy regimens. Treatment should be tailored according to that used in standard management of the transformed histology, and surgical resection is the mainstay of therapy.

Adenocarcinoma↗

PubMed1998

Metastatic germ cell tumors: modeling for response to chemotherapy.

PURPOSE: This study sought to determine factors that predict response to chemotherapy for patients with advanced germ cell tumors (GCTs), to evaluate different methods by which serum tumor markers can be used to predict response independent of assay method, and to develop criteria to guide allocation to clinical trials. METHODS: Pretreatment data from 796 patients treated with platinum-based chemotherapy on Memorial Hospital protocols from 1975 to 1990 were analyzed. Multivariate analyses were performed on a developmental data set (n = 597) to assess for independently significant predictors of response. Predictive models developed using these methods were confirmed on the validation set (n = 199). RESULTS: Independently significant factors for response included a mediastinal primary tumor (.015), pure seminomatous histology (.002), metastases to nonpulmonary visceral sites (bone, liver, and brain; .0001), and the pretreatment values of lactate dehydrogenase (LDH; .0001) and human chorionic gonadotropin (HCG; .0001). The likelihood of complete response (CR) was increased by seminomatous histology and decreased by the other factors. Serum levels of HCG and LDH could predict outcome independent of assay methodology. A model to predict good-, intermediate-, and poor-risk categories with CR rates of 92%, 76%, and 39%, respectively, was developed. CONCLUSION: The independent prognostic factors of serum tumor markers LDH and HCG, the sites of metastases, and the primary origin of GCTs can predict outcome in patients with advanced GCT. These factors should be considered in the allocation of patients with advanced disease to clinical trials and have been included in the new tumor-node-metastasis (TNM) staging systems developed for the American Joint Committee on Cancer (AJCC) and the Union Internationale Contre le Cancer (UICC).

Antineoplastic Combined Chemotherapy Protocols↗