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P R Exelby

Publications and source records attributed to P R Exelby.

At least 19 recordsLinked to original sources
PubMed1996

Renal cell carcinoma in childhood and adolescence: a retrospective survey for prognostic factors in 22 cases.

To identify prognostic factors for renal carcinoma in young patients, a retrospective analysis was performed of 22 patients (< or = 21 years of age) with histologically verified renal cell carcinoma. Demographic, staging, and treatment variables were collected in a database, and their effect on survival was determined using Kaplan-Meier probability distribution. The median age was 15.5 years (range, 3 to 21 years), and the male:female ratio was 13:9. Only three patients were black. Histopathologic examination showed 15 clear cell tumors, 4 mixed cell type, 2 papillary, and one well-differentiated adenocarcinoma. The median size of the primary tumor was 10 cm (range, 5 to 20). There were seven patients with stage I tumors, one with stage II, and 14 with stage IV. Complete resection of the primary tumor was accomplished in 12 patients. The overall 5-year survival rate was 30% (confidence interval, 20% to 40%). The 5-year survival rate was better for patients who had complete resection of the primary tumor (60% v 10%). Unresectability was associated with involvement of nodes and/or occurrence of metastases, thus an independent effect of complete resection on survival could not be demonstrated. The data showed that age, tumor size, location, and histology were not predictors of outcome; tumor stage and complete surgical resection were the only meaningful prognostic factors. The presentation of renal cell carcinoma as a localized or systemic disease may reflect a twofold biological behavior. In the first group, the disease is curable with resection, in the second, it is unaffected by surgery or adjuvant therapy. In light of the very low incidence of this renal malignancy in childhood, prospective multicenter studies will be required to improve the poor therapeutic results.

Adolescent↗
PubMed1995

Pediatric desmoid tumor: retrospective analysis of 63 cases.

PURPOSE: This study was conducted to evaluate clinical prognostic factors predictive of the probability of recurrence of desmoid tumor (DT). PATIENTS AND METHODS: Sixty-three patients with histologically confirmed diagnosis of DT were retrospectively studied. Median age at diagnosis was 13 years. Patient distribution by site was as follows: 61% extremities, 18% head and neck, 13% trunk (including 5% intraabdominal), and 8% multicentric lesions. All patients had partial or complete resections; 20 patients also received radiotherapy and/or chemotherapy. RESULTS: At a median follow-up time of 6 years since first treatment, the overall actuarial probability of having one or more recurrences was 75%. Age, sex, site, size, or number of previous recurrences had no significant impact on the likelihood of recurrence. The only factor associated with an increased proportion of recurrence-free patients was a negative margin of resection (70% v 15% with positive margins; P = .006). Of the four patients with more than 3 years follow-up since chemotherapy, two recurred, and of the 11 patients with the same follow-up after radiotherapy, four recurred, including two of five patients who received a dose of 50 Gy or more. No deaths directly related to tumor invasion were observed. CONCLUSION: A surgical approach aiming at clear margins is presently the best treatment option. When this cannot be accomplished without severe disfigurement or function impairment, partial resection is an acceptable alternative, but one associated with a high risk of regrowth. Whether adjuvant strategies should be used in this situation remains to be addressed.

Adolescent↗
PubMed1994

A prospective randomized double-blind trial of bolus urokinase in the treatment of established Hickman catheter sepsis in children.

BACKGROUND: The incidence of Hickman catheter sepsis is 10% to 40%, with resultant catheter loss in one third of infections. Urokinase causes dissolution of colonized intracatheter fibrin thrombi and may improve salvage. STUDY AIMS: To evaluate the efficacy of 12-hour-interval slow-push urokinase infusion in addition to standard antibiotic therapy in the treatment of catheter sepsis in a pediatric oncology population. METHODS: A two-arm randomized double-blind trial was undertaken, with catheter salvage rate as the end point. Patients with Hickman catheter sepsis were randomized after culture data confirmed the diagnosis. The study drug was administered by a slow intravenous push and given at 12-hour intervals for a total of four doses. The catheters were aspirated after 1 hour. RESULTS AND CONCLUSIONS: The trial was stopped after 41 patients were entered into the study; 18 patients received a placebo, and 23 received the urokinase. In the placebo group, six catheters were lost; in the urokinase group, eight were lost. The rate of bacterial clearance was equivalent for both. After administration of the study drug, each group had three episodes of fever and chills; two of these resulted in hypotension (one in each group). The authors conclude that slow-push urokinase infusion during established Hickman catheter sepsis does not result in improved catheter salvage or bacterial clearance. Slow intravenous push infusions in this setting may provoke hemodynamic instability even after initiation of antibiotics.

Bacteria↗
PubMed1993

Liposarcoma in patients younger than or equal to 22 years of age.

BACKGROUND: There have been few reported series of liposarcomas in patients younger than or equal to 22 years of age. METHODS: A retrospective analysis of all patients presenting with liposarcoma between 1949-1990 at Memorial Sloan-Kettering Cancer Center with age at diagnosis younger than or equal to 22 years was performed. Variables evaluated for their predictive effect on survival included anatomic location of the primary, size, and completeness of surgical resection. RESULTS: Eighteen patients were identified. Only 1 patient (6%) presented with a high-grade lesion, and in 13 patients (72%), the myxoid subtype was observed. All but one patient undergoing complete resection remain disease-free 1.3-29.1 years after treatment, while all patients with gross residual tumor have died from disease. Two of three patients with microscopic residual at resection are disease-free 2 and 11.8 years after diagnosis with the addition of external beam radiation therapy. CONCLUSIONS: The authors conclude that complete surgical resection is crucial for survival in young patients with liposarcoma and the external beam radiation therapy may be effective against microscopic residual.

Adolescent↗
PubMed1993

Long-term follow-up of patients treated with COMP or LSA2L2 therapy for childhood non-Hodgkin's lymphoma: a report of CCG-551 from the Childrens Cancer Group.

PURPOSE: We analyzed the long-term results of a Childrens Cancer Group (CCG) randomized study comparing cyclophosphamide, vincristine, methotrexate, and prednisone (COMP) versus LSA2L2 as treatment for childhood non-Hodgkin's lymphoma. The initial results were previously reported (N Engl J Med 308:559, 1983). PATIENTS AND METHODS: A total of 429 patients are reported here, 68 with localized disease and 361 with disseminated disease. The distribution of disseminated-disease patients by histologic type was 164 lymphoblastic, 60 large-cell, and 137 undifferentiated lymphomas. Median follow-up duration of surviving patients is 8 years. RESULTS: Event-free survival (EFS) of patients with localized disease was 84% at 5 years. No differences were seen between the two treatment regimens. Results for patients with disseminated disease was dependent on histologic subtype: patients with lymphoblastic lymphoma did better when treated with LSA2L2 (5-year EFS of 64% v 35% for COMP); COMP produced better results for patients with undifferentiated lymphoma (5-year EFS of 50% v 29% for LSA2L2). Results for large-cell lymphoma patients were similar (5-year EFS of 52% for COMP v 43% for LSA2L2). Five percent of patients died of treatment-related complications while on therapy (primarily infections). Only four deaths without progression have been observed off-therapy (two from restrictive lung disease, one from an acute asthma attack, one from colon cancer). Patient survival rates after recurrence were poor. CONCLUSION: Treatment success can be expected in 84% of pediatric patients with localized non-Hodgkin's lymphoma. For patients with disseminated disease, treatment success can be expected in 64% of those with lymphoblastic and 50% of those with undifferentiated or large-cell disease. To date, late adverse events are rare.

Adolescent↗
PubMed1992

A prospective analysis of vascular access device-related infections in children.

To identify significant predictors of device-related infections, we performed a prospective, nonrandomized analysis of our experience with vascular access devices over a 2-year period in a pediatric oncology population. Variables analyzed included: (1) age at placement, (2) sex, (3) underlying disease, (4) type of device used (catheter v port), and (5) total white blood cell count at placement. Quantitative microbiologic criteria were used for diagnosis of bacteremia while clinical and microbiologic criteria were used in diagnosis of tunnel/port/site infections. During the study period a total of 351 devices, comprising 78,159 days in situ, were placed and data for univariate and multivariate analysis were available on 271 (77%). The mean age at placement was 7.2 +/- 4.7 years for catheters and 9.5 +/- 4.8 years for implantable devices (P less than or equal to .01). Significant predictors of device-related infections in univariate analysis were type of device (P less than or equal to .0001) and age (P less than or equal to .002). External catheters and age less than or equal to 7 years were associated with increased risk of infection. Underlying disease had a marginal effect on the infection rate (P = .08). In multivariate analysis, device type (P less than or equal to .0001) and age (P less than or equal to .002) continued to affect infections, whereas underlying disease demonstrated only a borderline effect (P = .14). We conclude that device type and age significantly affect the rate of device-related infections. These data support increased use of implantable devices in pediatric oncology patients.

Catheters, Indwelling↗
PubMed1992

Prognostic factors and outcome in patients 21 years and under with colorectal carcinoma.

This study aims to identify significant predictors of survival in pediatric and adolescent colorectal carcinoma. We retrospectively analyzed our experience with 29 histologically verified cases, of which 20 were resected for cure. Variables analyzed as predictors of survival included: (1) resectability, (2) regional nodal involvement, (3) depth of invasion, (4) grade, and (5) interval from symptom onset to diagnosis. Signet ring or anaplastic lesions were considered high grade. Survival curves were generated on both the overall group and those resected for cure. Multivariate analysis was performed on the overall group. The median age at diagnosis was 19 years (range, 10 to 21). Median follow-up in survivors was 4.7 years. Signet ring tumors occurred in 45% and another 24% were poorly differentiated. Seventy-six percent presented with regional lymph node metastases. The median survival for the overall group was 16 months, whereas that for those undergoing complete resection was 33 months. In patients undergoing resection for cure, grade (P = .005), regional nodal involvement (P = .007), and depth of invasion (P = .03) were significant predictors of outcome in univariate analysis. In the overall group these variables as well as resectability and distant metastases were significant in univariate analysis. In multivariate analysis high-grade lesions and lymph node involvement were highly correlated, as were resectability and metastases. Thus, either variable (but not both) of each pair added information to the multivariate model. In patients resected for cure, positive nodes or high histological grade became the only significant predictors of survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

High-dose melphalan with 6-hydroxydopamine-purged autologous bone marrow transplantation for poor-risk neuroblastoma.

Long-term results are presented of 28 patients who were diagnosed with neuroblastoma at more than 12 months of age and who received melphalan 180 mg/m2 (n = 6) or 240 mg/m2 (n = 22) to consolidate remissions of Stage IV disease or to control refractory disease. Twenty-four patients also received dianhydrogalactitol 180 to 240 mg/m2, and 11 received total body irradiation 450 to 600 cGy. Autologous bone marrow transplantation (ABMT) was performed with marrow that was unpurged (n = 2) or purged ex vivo (n = 26) with 6-hydroxydopamine (6-OHDA) 20 micrograms/ml plus ascorbate 200 micrograms/ml. The median time to an absolute neutrophil count of 500/microliters was 21 days and to self-sustaining platelet counts more than 20,000/microliters, 28 days. One patient required infusion of unpurged reserve marrow. Two groups of patients underwent ABMT: (1) 17 patients (Group I) who were in first remission a median of 7 months after diagnosis; and (2) 11 patients (Group II) who had refractory disease or were in second remission. For Group I, event-free survival was 29% at 12 months and 6% at 24 months post-ABMT. All Group II patients died of disease or ABMT-related toxicity. Overall, of the 28 patients, one is a long-term relapse-free survivor; five died of ABMT-related toxicity; ten patients with tumors present at ABMT had progressive disease within 6 months of ABMT; and 12 patients with no measurable disease at ABMT relapsed 4 to 32 months (median, 12) post-ABMT. Among the latter, six relapses involved the primary site, and six were restricted to distant sites. These results--in accord with the long-term outcome in other series--suggest that for neuroblastoma high-dose melphalan cannot be relied on to ablate residual disease or to salvage patients with refractory tumors. In addition, the pattern of relapse in several patients could be explained by infusion of incompletely purged autografts; this would support recent laboratory evidence that 6-OHDA/ascorbate is a suboptimal purging method.

Adolescent↗
PubMed1991

Extracranial primitive neuroectodermal tumors. The Memorial Sloan-Kettering Cancer Center experience.

The clinical data of 54 patients (57% males) with extracranial primitive neuroectodermal tumors (PNET) seen over a 20-year period at Memorial Sloan-Kettering Cancer Center were reviewed. The age at diagnosis ranged from 1 month to 81 years (median, 17 years). One PNET arose in a previously irradiated site. One patient had an unaffected identical twin. Primary sites were thoracopulmonary (n = 25), pelvis (n = 12), retroperitoneum or abdomen (n = 10), limbs (n = 5), neck (n = 1), and unknown (n = 1). At diagnosis, epidural extension was present in 13 patients with truncal primaries, and 11 patients had distant metastases. All of the latter died with disease. Progression-free survival (PFS) among the 43 patients with localized tumors (all greater than 5 cm) was 25% at 24 months. Two of 13 patients who relapsed after more than 12 months without therapy were long-term survivors. Patients with localized PNET who had resection of all gross disease within 3 months of diagnosis had a significantly longer PFS (P = 0.0003). Radiation therapy caused tumor shrinkage but was not curative of measurable disease. A dose-response effect was evident with the most commonly used drug, cyclophosphamide. Myeloablative regimens using melphalan (n = 8) or thiotepa (n = 1) with autologous bone marrow rescue were not clearly beneficial. The treatment results favor: (1) early surgical removal, (2) dose-intensive use of drugs active against PNET (especially cyclophosphamide), and (3) radiation therapy to ablate residual microscopic disease.

Adolescent↗
PubMed1991

Wilms' tumor 1991. Clinical evaluation and treatment.

Wilms' tumor is the most common malignant tumor of the kidney in children. Although only 500 cases per year are diagnosed in the US, the tumor has been studied extensively in the National Wilms' Tumor Committee Cooperative Studies. These prospective studies have led to improved survival and at the same time reduced treatment and complications in the more favorable cases. Similar results have been shown by the European cooperative study group SIOP using different treatment protocols. These studies have identified a group of tumors with unfavorable histology that are more resistant to treatment and will require more intensive protocols. Diagnosis of Wilms' tumor by the finding of a large flank mass in an otherwise healthy-appearing child is usually easy. Imaging techniques of CT or IVU will give accurate confirmation of Wilms' tumor in 95% of children. Modern treatment in the US by radical nephrectomy followed by chemotherapy with or without radiotherapy depends on tumor stage and histology. Early-stage tumors with favorable histology can be controlled by shorter courses of two-drug treatment (dactinomycin and vincristine) without radiation. Advanced tumors respond to treatment but require more intensive chemotherapy combined with radiation. The final challenge is the child with a tumor of unfavorable histology, particularly if there is advanced-stage disease. Whereas Wilms' tumor showing favorable histology now has a survival rate exceeding 90%, survival of those with tumors of unfavorable histology remains poor. The European (SIOP) studies have shown similar survival figures using preoperative chemotherapy. This technique produces shrinkage of tumors, making them less hemorrhagic and producing a lower incidence of rupture at subsequent surgery. Preoperative chemotherapy does not change the histologic diagnosis of Wilms' tumor and is a useful alternative approach for the large hemorrhagic or infiltrating tumors.

Child↗
PubMed1990

Prognostic factors in bladder and bladder-prostate rhabdomyosarcoma.

In order to examine surgical factors predictive of fatal outcome in patients presenting with histologically verified rhabdomyosarcoma of the urinary bladder, we performed a retrospective analysis of cases presenting between the years 1970 and 1985 and treated by protocol. Twenty-five patients were identified and data were complete for univariate and multivariate analysis on all. Staging was done according to the criteria of the International Union Against Cancer (TNM). Median age at presentation was 14.7 years and 10 patients were younger than 10 years. Median follow-up was 4.8 years overall and 8.4 years in survivors. Four patients presented with involvement of regional lymph nodes and three with distant metastases. Complete surgical resection, defined as negative microscopic margins, was accomplished by total cystectomy in 14 patients, and partial cystectomy in two. In this group cystectomy was performed prior to chemotherapy and radiation in five and after in 10 (persistent disease). Three salvage cystectomies were performed in patients who recurred after initial complete responses to chemotherapy and radiation therapy. Thirteen patients received a median of 3,000 cGy (range, 1,800 to 5,000 cGy) of external beam pelvic irradiation, and two received brachytherapy. All patients received multiple agent chemotherapy according to either the T2 or T6 protocol. There are 11 disease-free survivors (44%) and 10 of these have been followed for more than 6 years. One patient is alive with disease 6.5 years after diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Factors predictive of mortality in pediatric extremity rhabdomyosarcoma.

In order to examine factors predictive of fatal outcome in children presenting with histologically confirmed extremity rhabdomyosarcoma, we performed a retrospective analysis of our institutional experience from 1970 to 1985. Thirty-five patients were identified and staged according to international criteria (TNM). Variables evaluated for their predictive effect on fatal outcome included (1) tumor invasiveness, (2) tumor size, (3) anatomic location of the primary, (4) regional lymph node involvement, (5) distant metastases at presentation, (6) complete surgical resection, (7) use of amputation, and (8) alveolar histologic subtype. Significant predictors of mortality included (1) tumor invasiveness (P less than or equal to .0001), (2) regional node involvement (P less than or equal to .0002), (3) distant metastases at the time of presentation (P less than or equal to .001), (4) alveolar histology (P less than or equal to .001), (5) size of primary (P less than or equal to .007), and (6) completeness of surgical resection (P less than or equal to .05). In multivariate analysis, local tumor invasiveness was the most important predictor of fatal outcome with an associated relative risk of 18. We conclude that local tumor invasiveness is the most important determinant of clinical stage.

Adolescent↗
PubMed1988

Recurrence and morbidity in differentiated thyroid carcinoma in children.

The management of differentiated thyroid cancer in childhood is controversial. In particular, the role of aggressive surgical treatment has been questioned. This study was performed to identify those factors that are predictive of recurrence and morbidity following treatment through use of a multivariate model. The records of all patients 17 years of age or less admitted in the last 35 years with histologically confirmed differentiated thyroid carcinoma were reviewed. Data were sufficient for multivariate analysis in 93. The mean age at diagnosis was 13.3 years, and the median period of follow-up was 20 years. Seventy-one percent of the patients had nodal metastases. There were no deaths from thyroid carcinoma in this series, and the overall recurrence rate after initial treatment was 34%. Multivariate analysis demonstrated that only age (p less than or equal to 0.07) and histologic subtype (p less than or equal to 0.01) were predictive of time to recurrence. Major morbidity was a function of age (p less than or equal to 0.007) and extent of thyroid surgery (p less than or equal to 0.01). Probability of minor complications was predicted by use of radical neck dissection (p less than or equal to 0.02). Use of total or subtotal thyroidectomy or of radical neck dissection in children does not prevent recurrence and is associated with an increased risk of complications. We conclude that these procedures should be avoided in pediatric patients.

Adolescent↗
PubMed1986

The objectives and importance of operative staging of children with cancer.

Modern multidisciplinary treatment of childhood cancer has made extent of disease evaluation important for proper treatment planning. Accurate staging is essential to cooperative group studies and for comparing treatment modalities at different centers. Operative staging plays an important role where clinical or imaging methods are limited, as in abdominal Hodgkin's disease or regional nodal metastasis. Operative staging is carried out either as a special diagnostic procedure, as in lymphoma, or as part of a planned surgical resection of a solid tumor. For lymphomas: Operative staging of abdominal Hodgkin's disease is required where protocols include involved field irradiation and sparing of normal growing tissue in the child. In non-Hodgkin's lymphoma, bulky abdominal tumor may be surgically evaluated after intensive chemotherapy either in delayed primary surgery or in second look procedures. Residual tumor may be excised or tagged with clips for localized irradiation to the tumor sparing normal abdominal organs. For solid tumors: During surgical resection of neuroblastoma, Wilms' tumor and rhabdomyosarcoma, the correct procedure involves regional staging either by formal node dissections or by multiple biopsies to determine extent of spread. Regional node dissections are often part of a correct cancer operation for cure, but also give staging information unobtainable by other methods. The surgeon must plan every procedure carefully with the aim of curing the patient and also deriving maximum information from the operation to enable correct planning of further treatment.

Abdominal Neoplasms↗
PubMed1984

Studies on the pathology of non-Hodgkin's lymphoma of childhood. I. The role of routine histopathology as a prognostic factor. A report from the Children's Cancer Study Group.

Between April 1977, and August 1980, the Children's Cancer Study Group (CCSG) conducted a clinical trial of childhood non-Hodgkin's lymphoma (NHL), randomizing 256 patients to one of two treatment regimens. A 4-drug regimen (regimen 1, modified cyclophosphamide, Oncorin [vincristine], methotrexate, prednisone [COMP] ) was compared with a 10-drug regimen (regimen 2, modified LSA2-L2). Using the Rappaport classification, the review pathologist diagnosed the 213 evaluable tissue specimens as follows: lymphoblastic (LC), 73; Burkitt's tumor (BT), 40; "undifferentiated" non-Burkitt's type (NB), 67; large cell or "histiocytic" lymphoma (HI), 29; and other types (OT), 4. Concurrence in classification between the review and institutional pathologists was poor when using the above four categories; however, concurrence was 88% between the review pathologist and other hematopathologists, and 99% when classifying the specimens as lymphoblastic or nonlymphoblastic. For patients with nonlocalized disease, this randomized controlled study demonstrated a new important correlation of histopathology with the effectiveness of treatment. When analyzed without stratification into lymphoblastic and nonlymphoblastic types, the two regimens showed identical relapse free survival (RFS) curves for patients with nonlocalized involvement. However, when patients were stratified according to histologic classification, regimen 2 was superior to regimen 1 for patients with lymphoblastic lymphoma, achieving 74% RFS at 30 months compared to 31% for regimen 1 (P = 0.001). Conversely, those with nonlymphoblastic types (BT, NB, HI) treated with regimen 1 had a 58% RFS at 30 months compared to 32% for those treated on regimen 2 (P = 0.01). This study demonstrates that proper, routine histopathologic classification of NHL is the best criterion for choice of therapy in children with nonlocalized involvement. As a result of this study, all patients with nonlocalized disease, diagnosed after August 1980, were no longer randomized but were assigned to the appropriate treatment regimen based on prospective review of histopathology.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

Splenectomy after angiographic embolization of the splenic artery in patients with massive splenomegaly and severe thrombocytopenia, in juvenile subacute myelomonocytic leukemia.

Splenectomy for massive splenomegaly in thrombocytopenic patients refractory to platelet transfusions carries increased surgical risks. Blocking of the splenic artery may reduce the size of the organ, prolong the survival of transfused platelets, and reduce the surgical complications. We describe four cases of extreme splenomegaly and thrombocytopenia where successful splenectomy was carried out after angiographic embolization of the splenic artery in children with juvenile chronic myelogenous leukemia. Significant improvement was observed in platelet counts and in the survival of platelets after transfusions in three of the patients. There was a concomitant decrease in transfusion requirements. Isoimmunization prevented prolonged platelet survival in the fourth case. We recommend earlier splenectomy in these patients to reduce transfusion requirements and delay the onset of poor platelet survival after transfusions.

Blood Transfusion↗
PubMed1984

Treatment of genitourinary rhabdomyosarcoma in children.

We report on 27 children with rhabdomyosarcoma of the bladder, prostate, uterus, cervix and vagina treated with combined therapy of surgery, radiotherapy and multiple drug chemotherapy. Of the 27 patients 18 are alive for 13 to 147 months (median 86 months) and 9 have retained a functional bladder. Extirpative surgery followed by adjuvant chemotherapy and occasionally radiation therapy was most effective for local tumor control and 7 of 10 patients survived, including 5 with an intact functional bladder. Primary use of chemotherapy in 13 patients with extensive disease resulted in complete tumor control in only 3 but 7 survived, including 4 with an intact bladder. Radiation therapy used concomitantly with chemotherapy failed to control the local tumor but with subsequent extirpative surgery all 4 patients survived.

Adolescent↗