Biomedical subjects

G M Haase

Publications and source records attributed to G M Haase.

At least 55 records · Page 3Linked to original sources

PubMed1994

The implications of surgical quality assurance in cancer clinical trials.

Prospective clinical trials are used to evaluate therapeutic interventions. Because surgery is involved in the diagnosis, staging, and therapy of solid malignancies, active surgical leadership in these cancer studies is important. There are currently barriers to widespread surgical participation in clinical trials. This report defines the obstacles as well as documents efforts to overcome them and improve surgical quality assurance in cooperative group research. The surgical leadership of several clinical cooperative groups sponsored by the National Cancer Institute (NCI) were interviewed. Cooperative group reports were analyzed with respect to internal audits, quality assurance and activities of surgical monitoring committees. Minutes from meetings of the NCI's workshops on "Surgeons in Clinical Trials" were reviewed. Six concerns present impediments to surgical quality in clinical trials. To address these, substantive surgical leadership is being developed throughout the cooperative group system. Surgical co-principal investigators for institutions and protocols are being appointed. Uniform surgical standards and operative guidelines are being developed. Surgical data review occur at the local institution as well as through central audits and surgical monitoring committees. Coordinators in surgical data management are being trained. Surgical education is organized at cooperative group meetings and disseminated to the surgical community by seminars, workshops, audiovisual teaching sessions, and scientific publications. Surgeons are playing increasing leadership roles in the cancer trials performed by cooperative groups. Surgical leaders are dedicated to a broad-scale quality assurance effort. Enhanced surgical commitment, widespread clinical participation, and focused leadership should affect a high level of surgical quality care in clinical trials research.

Clinical Trials as Topic↗

PubMed1994

Electron beam intraoperative radiation therapy for pediatric neoplasms.

BACKGROUND: Intraoperative radiation therapy (IORT) has potential advantages over conventional external beam radiation in that a single large dose is delivered to the tumor and its regional bed at the time of surgical exploration. The therapeutic ratio is enhanced by direct tumor visualization, precise treatment volume, and exclusion of normal organs. In childhood, local tumor control is critical for lesions that cannot be totally excised or residual disease not ablated by systemic therapy. METHODS: During the past decade, the authors evaluated IORT in pediatric patients with unresectable or recurrent tumors. Fifty-nine patients were treated, 48 for advanced malignant disease and 11 for histologically benign but locally aggressive tumors. Sixty-four operations were performed, during which 84 separate radiation fields were used. High energy electrons at 5-11 MeV were delivered at a dose of 1000-1700 cGy to a tissue depth of 0.5-3 cm. RESULTS: Of 25 children with advanced neuroblastoma, 15 were alive 14-104 months (mean, 51 months) after treatment. The survival of all patients with solid malignancies was 63%. Local tumor control was achieved in 75% of children with cancer and 91% of those with benign tumors. Complications of IORT at the doses used were trivial. CONCLUSIONS: Electron beam therapy can be safely and efficiently delivered to young patients during operations intended to treat the primary tumor. The outcome achieved for overall survival and local control of the primary tumor is encouraging, and an acceptable complication rate during intermediate to long-term follow-up has been noted.

Adolescent↗

PubMed1994

Indications for surgical intervention for gastrointestinal emergencies in children receiving chemotherapy.

BACKGROUND: Abdominal pain in children receiving chemotherapy for cancer presents the clinician with unique problems due to the altered immunity of these patients or to the oncologic setting. The major clinical decisions regarding these patients are to determine if and when operative intervention is indicated. METHODS: A retrospective study was done to examine the clinical, radiographic, and laboratory findings that indicate the need for surgical intervention. Sixty-eight of 1090 children who underwent treatment for cancer from October 1982 to December 1990 developed abdominal complaints requiring them to be hospitalized. Nineteen of these patients underwent exploratory laparotomy (operative), and the other 49 were observed (nonoperative). RESULTS: No significant differences were observed in the phase of chemotherapy, treatment with vincristine or corticosteroids, or the hematologic indices between the operative and nonoperative groups. Eighteen of nineteen patients survived their surgeries. Seventeen (89%) of these laparotomies were positive based on the surgical pathology and the operative report. Peritoneal signs on physical examination (P < 0.001) or pneumatosis intestinalis on abdominal radiographs correlated with positive laparotomies (P = 0.001). CONCLUSIONS: Peritoneal signs on physical examination or pneumatosis intestinalis on abdominal X-rays were associated with and specific for the presence of acute surgical disease of the abdomen in immunocompromised pediatric oncology patients.

Abdomen, Acute↗

PubMed1994

Allogeneic versus autologous purged bone marrow transplantation for neuroblastoma: a report from the Childrens Cancer Group.

PURPOSE: We have compared the toxicity, relapse rate, and progression-free survival (PFS) of high-risk neuroblastoma patients receiving identical induction therapy and myeloablative chemotherapy plus total-body irradiation (TBI) followed by allogeneic or autologous purged bone marrow transplantation (BMT). PATIENTS AND METHODS: Fifty-six patients with high-risk neuroblastoma underwent BMT at investigator and parent option if they did not have progressive disease after induction chemotherapy with cisplatin, cyclophosphamide, doxorubicin, and etoposide. After surgery and local radiation to residual tumor, myeloablative therapy consisting of etoposide, melphalan, cisplatin, and TBI was given followed by BMT. Patients with human leukocyte antigen (HLA)-compatible siblings received allogeneic bone marrow (n = 20). The remaining patients (n = 36) received autologous bone marrow that had undergone multimodality purging and had no remaining detectable tumor cells by immunocytology. RESULTS: Four of 20 allogeneic patients had a treatment-related death, compared with three of 36 autologous patients (P = .21). The relapse rate among allogeneic BMT patients was 69%, compared with 46% for autologous BMT patients (P = .14). The estimated PFS rates 4 years after BMT were 25% for allogeneic BMT patients and 49% for autologous BMT patients (P = .051). CONCLUSION: Overall outcome for patients with neuroblastoma given this same induction therapy followed by autologous purged marrow was similar to that with allogeneic marrow, although bias in patients selection cannot be excluded in a nonrandomized comparison.

Adolescent↗

PubMed1994

Head and neck neuroblastoma.

Primary neuroblastoma of the head and neck is rare. The clinical presentation and physical findings are related to the child's age, the stage and location of the primary tumor, and its attendant biological behavior. The differential diagnosis is varied, and initial evaluation includes a thorough physical examination, selected laboratory studies, and specific high-yield imaging techniques. The prognosis of these lesions has been increasingly favorable, even when the disease is not localized. Carefully planned surgical approaches provide local control, and radiation and chemotherapy may be beneficial in more extensive tumors. Second malignancies occur after treatment, and long-term follow-up is necessary.

Adolescent↗

PubMed1993

Preoperative therapy for intracaval and atrial extension of Wilms tumor.

BACKGROUND: Primary surgical management of Wilms tumor with intravascular tumor extension is associated with significant morbidity. Retrospective analysis of a group of Wilms tumor patients with intravascular tumor extension treated with preoperative therapy was performed to evaluate the feasibility of this approach. METHODS: Thirty children with caval (15 patients) or atrial (15 patients) extension of Wilms tumor who received preoperative therapy were reviewed. Patients were classified according to the stage of the disease as follows: (1) Stage III, 7 patients; (2) Stage IV, 18 patients; and (3) Stage V, 5 patients. The histologic type was favorable in 20 patients, anaplastic Wilms tumor in 7, and unknown in 3. All of the children received preoperative chemotherapy, ranging from 1-16 weeks with an average of 7.2 weeks. RESULTS: One child died of progressive disease and another from toxicity before surgery. In 23 patients, a decrease in the size of the intravascular extension was noted preoperatively, without tumor embolization in any case. There was complete resolution of tumor thrombus in seven patients. Two-year survival for the entire group is 70%, with a median follow-up period of 21 months. CONCLUSIONS: The use of preoperative therapy is appropriate in selected patients with extensive intravascular tumor involvement. Surgical management was facilitated in the majority of cases due to shrinkage of the primary tumor and reduction in the size of the tumor thrombus.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1993

Patterns of care.

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Adolescent↗

PubMed1993

Small bowel obstruction after nephrectomy for Wilms' tumor. A report of the National Wilms' Tumor Study-3.

OBJECTIVE: This study was undertaken to define the incidence and etiology of small bowel obstruction (SBO) after nephrectomy for Wilms' tumor. SUMMARY BACKGROUND DATA: Intestinal obstruction is one of the most common postoperative complications after nephrectomy for nephroblastoma. However, few reports have evaluated risk factors for SBO. Radiation therapy has been associated with increased intestinal complications in some adult cancer patients, but this has not been reported in children undergoing cancer surgery. METHODS: Postoperative SBO occurred in 131 of 1,910 children (6.9%) enrolled in the Third National Wilms' Tumor Study (NWTS). The etiology of the SBO was bowel adhesions in 104 cases, intussusception in 17, internal hernia in 2, and uncertain in the remaining 8 children. RESULTS: The factors found to be of potential importance in explaining the incidence of SBO were higher local tumor stage, extrarenal intravascular involvement, and en bloc resection of other organs at the time of nephrectomy. The incidence of postoperative SBO was not increased in children who received postoperative radiation therapy. CONCLUSIONS: Although the overall incidence of SBO after nephrectomy for Wilms' tumor is comparable to that after other major abdominal operations in children, it can be responsible for significant morbidity. There were 4 children among the 1,910 patients with infectious complications of SBO, which contributed to their death.

Child, Preschool↗

PubMed1993

Incidental appendectomy during nephrectomy for Wilms' tumor.

Incidental appendectomy is frequently performed during nephrectomy for Wilms' tumor. The rationale for this approach is that the onset of appendicitis during a period of neutropenia after chemotherapy may cause increased morbidity. Additionally, children receiving chemotherapy or radiation therapy, or both, may experience abdominal pain, producing a diagnostic dilemma if the appendix is still present. We reviewed the charts of 1,910 children enrolled in the Third National Wilms' Tumor Study who underwent primary nephrectomy. Four hundred and fifty-five patients (23.8 percent) had appendectomy at the time of nephrectomy. An inversion appendectomy was performed upon 188 patients, and the appendix was excised in 267. Infectious complications and postoperative intestinal obstructions occurred with equal frequency in children who did or did not undergo appendectomy. The median follow-up period for the entire group of patients was 5.1 years. Only three of the 1,455 children (0.2 percent) who did not have an incidental appendectomy had appendicitis at two, seven and ten months after nephrectomy. None of the three children experienced any perioperative morbidity after appendectomy. These data suggest that incidental removal of the appendix is not essential for children undergoing removal of a Wilms' tumor.

Appendectomy↗

PubMed1992

Superior mesenteric artery injury during nephrectomy for Wilms' tumor.

Iatrogenic injury to the aorta or its major branches during nephrectomy for Wilms' tumor in children is rarely reported but may be more common than is currently acknowledged. We identified four patients with ligation of the superior mesenteric artery (SMA) that occurred during nephrectomy for nephroblastoma and another child in whom SMA thrombosis developed postoperatively. All of the tumors were on the left side. Interruption of the SMA was recognized intraoperatively in all four children, and primary repair was done. In three patients, appearance of the bowel remained normal before repair of the injury. Three of the arteries were repaired by primary reanastomosis, and one was joined with an interpositioned hypogastric artery graft. None of these patients had gastrointestinal complications postoperatively. In the fifth patient, SMA thrombosis developed after repair of an aortic tear during nephrectomy. This patient required subsequent small bowel resection for bowel infarction and died in the perioperative period. Every surgeon treating children with Wilms' tumor should be aware of the possibly distorted vascular anatomy and take precautions to avoid such a significant injury. Attempts at early ligation of the vessels may not be justified until the renal vasculature is clearly identified.

Child, Preschool↗

PubMed1992

Resection of the primary tumor is appropriate for children with stage IV-S neuroblastoma: an analysis of 37 patients.

Current recommendations for treatment of children with IV-S neuroblastoma (NB) indicate that "supportive care is the cornerstone of therapy" and resection of the primary tumor is not mandated. The presentation and clinical management of 37 IV-S NB patients from three pediatric oncology centers were retrospectively reviewed. The 22 boys and 15 girls presented at an average age of 107 days (range, 4 to 616 days). Primary tumor sites were identified in the adrenal gland in 19 children, the thorax in 5, the retroperitoneum in 4, and 1 each in the pelvis and kidney. At the time of presentation, metastatic disease was documented in the liver (27), bone marrow (19), skin (7), and regional lymph nodes (7). Massive hepatomegaly (below the umbilicus) was demonstrated in 18 patients. Twenty-eight children (76%) have survived on average 90 months following diagnosis. Eight patients (22%) died; six of disease and two of complications of therapy (mean, 9.6 months). One child was lost to follow-up. Only 3 of the 37 patients (8%) were managed solely by supportive care and all are alive. Extirpation of the primary tumor was accomplished in 24 individuals (65%). Twenty patients underwent excision at diagnosis and four had delayed resection with few postoperative complications and no deaths related to resection. One death resulted from progression of disease in a child who had tumor removal. Chemotherapy as a single treatment or in combination with radiation was used in 10 children with three children surviving (30%).(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

PubMed1992

Extrarenal Wilms' tumor: results of the National Wilms' Tumor Study.

Extrarenal Wilms' tumor is extremely rare and occurs predominantly in children. Eight cases of extrarenal Wilms' tumor were reported to the National Wilms' Tumor Study from 1980 to 1986. Patients were followed in the study and not randomized to a particular treatment protocol. Seven patients had a favorable histology. One tumor located in the sacrococcygeal region showed immature teratoma with nephroblastic tissue. The embryogenesis of extrarenal Wilms' tumor is controversial; however, tumor containing teratomatous elements most likely represents a different embryologic origin and, therefore, should be classified separately. All eight patients were treated with operative excision and chemotherapy. Seven of the eight patients were disease-free with a mean follow-up of 34.3 months. It can be inferred from this small group of patients that the prognosis is comparable to intrarenal Wilms' tumor in the National Wilms' Tumor Study.

Child, Preschool↗

PubMed1992

Surgical complications after nephrectomy for Wilms' tumor.

We reviewed the charts of 1,910 children enrolled in the Third National Wilms' Tumor Study who underwent primary nephrectomy. Four hundred and ninety-five surgical complications occurred in 379 children (19.8 percent). Patients with inoperable tumors, bilateral renal tumors, peroperative therapy and those who refused treatment were excluded from this review. The most common complication was intestinal obstruction, which occurred in 132 patients (6.9 percent). This was followed by extensive intraoperative hemorrhage (112 patients), defined as blood loss exceeding 50 milliliters per kilogram of body weight. Intraoperative injuries to other visceral organs (including intestine, liver and spleen) occurred in 21 children and extensive vascular injuries were reported in 27 patients. There were nine deaths attributed to surgical complications (0.5 percent), only one of which was intraoperative. Survival of patients with complications was similar to patients without complications when stratified by histologic study and stage. Factors associated with the development of surgical complications included advanced local tumor stage at diagnosis, intravascular tumor extension and resection of other visceral organs at the time of nephrectomy. Complete removal of the tumor is important, but not at the expense of radical removal of adjacent structures, because of gross appearances at operation. They are often not invaded by the tumor, but rather are compressed, distorted or adherent without tumor infiltration. Identification of these groups will aid the surgeon in choosing the appropriate management for these patients at high risk. When initial exploration and precise surgical staging indicate that only a formidable operation will achieve total excision, shrinkage of the tumor with selective use of chemotherapy or radiotherapy, or both, may facilitate removal and decrease surgical morbidity. Preoperative therapy may also be the preferred approach for children with extensive intravascular tumor.

Actuarial Analysis↗

PubMed1991

Aggressive surgery combined with intensive chemotherapy improves survival in poor-risk neuroblastoma.

One hundred eighteen children with metastatic (Childrens Cancer Study Group [CCSG] stage IV), extensive regional (stage III), or stage II neuroblastoma with N-myc amplification received an intensive chemotherapeutic regimen of cis-platinum, etoposide, doxorubicin, and cyclophosphamide combined with persistent aggressive attempts at complete primary tumor resection. Fourteen patients were unevaluable and 42 left the study to be placed on bone marrow transplant protocols. The remaining 62 children were evaluated in detail. Complete excision was eventually accomplished in 39 patients (63%), 23 of whom are disease-free survivors after 8 to 47 months (median, 20 months). Twenty-three patients underwent partial excision or biopsy of their lesion and only 6 are alive without evidence of disease (P = .0011). Timing of surgery or site of tumor did not influence surgical outcome. N-myc oncogene expression could not predict which lesions would be completely resectable. Surgical complications occurred 21% of the time but the impact on the clinical course and chemotherapy administration was minimal. The ipsilateral kidney was removed with the tumor in 18 cases, 14 of which were during complete resection. Twelve of these children are disease-free survivors. With new intensive chemotherapy capable of eliciting an effective response from primary and metastatic neuroblastoma, aggressive surgical approaches for complete tumor resection are warranted and can be expected to improve patient outcome.

Adolescent↗

PubMed1991

Right atrial catheters in pediatric oncology: a patient/parent questionnaire study.

Venous access devices are an option offered to pediatric oncology patients to make their frequent blood sampling and intravenous therapy more tolerable. To determine the advantages and disadvantages of using these devices, a study comparing Mediport and Broviac catheters was conducted from August 1985 to August 1987 at The Children's Hospital, Denver, Colorado. This report will analyze results of the patient-parent acceptance questionnaire employed in that study. Overall, both the patients and their parents were very positive about the devices. Daily care of the Broviac and pain associated with accessing the Mediport were the only uniformly negative factors we encountered. These problems became unimportant when compared to the advantage of eliminating peripheral venipuncture.

Adolescent↗

PubMed1989

Improvement in survival after excision of primary tumor in stage III neuroblastoma.

Fifty-eight patients with stage III neuroblastoma (according to the Childrens Cancer Study Group) underwent 86 operative procedures. Initial diagnostic or therapeutic operations were followed by chemotherapy and radiation therapy, and second- or third-look procedures were performed on patients whose tumors showed evidence of clinical response. Complete resection was obtained during the initial procedure in 12 patients, during the second operation in 12 others, and at the time of the third procedure in two additional children. Twenty of these 26 patients have survived with no evidence of disease for a median duration of greater than 3 years since initiation of therapy. Only nine of the 32 patients in whom complete tumor excision could not be accomplished are still alive. The chemotherapy and radiation therapy employed in this protocol may have enhanced resectability in many patients. The site of the primary tumor does not seem to influence ease of resectability or outcome in this group. The "favorable" prognostic factors of patient age and histopathology of the tumor do not necessarily predict that the tumor will be resectable. While patients with complete resection at the time of the second operation had an outcome superior to those with incomplete resections, the influence of the inherent tumor biology or other selection factors on the eventual tumor resectability in these patients is not known. Extensive operative procedures were required to completely resect stage III tumors, and a moderate complication rate may be anticipated. However, this may be justifiable if complete tumor resection can be achieved and ultimate patient survival possibly enhanced.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1989

A surgical perspective on the current staging in neuroblastoma--the International Neuroblastoma Staging System proposal.

In the three most widely used neuroblastoma staging systems--Evans, Pediatric Oncology Group (POG), and TNM-Union Internationale Contre le Cancer (UICC)--few staging problems are presented by the completely resected tumor or with the patient who has metastatic disease. Difficulties arise with the localized tumor when there is extension across the midline and with the demonstration of lymph node involvement. A new International Staging System for Neuroblastoma (INSS) is proposed that incorporates both lymph node invasion and extension across the midline into surgical staging. Clear criteria for diagnosis are established and clinical responses are defined. New prognostic factors may be added. The surgical role remains significant in staging, diagnosis, and therapy. Use of a common system throughout the world would facilitate the evaluation of clinical trials and help achieve the goal of developing optimum therapy for the biologically different types of neuroblastoma.

General Surgery↗

PubMed1989

Excellent outcome of stage II neuroblastoma is independent of residual disease and radiation therapy.

The optimal management for patients with stage II neuroblastoma has not yet been established. In order to determine the impact of adding chemotherapy and/or radiation therapy to surgery, we reviewed by questionnaire 156 patients with stage II neuroblastoma treated by 28 Childrens Cancer Study Group (CCSG) institutions from 1978 to 1985. Survival and progression-free survival (PFS) were analyzed by life-table methods with respect to age at diagnosis, site and size of primary tumor, spinal cord involvement, extent of initial resection, and treatment in addition to surgery. The overall 5-year survival was 96%; the PFS was 90%, similar to previous CCSG studies. Age at diagnosis had a small impact on PFS, with 92% PFS for patients less than 2 years of age at diagnosis, and 84% for those greater than 2 (P = .10). The only site with an adverse outcome was the head and neck (n = 11), with a PFS of 68% compared with 93% for the remaining sites (P = .02). Size of primary and intraspinal extension of primary did not affect PFS. The extent of resection and subsequent treatment with radiation therapy and/or chemotherapy did not affect the PFS. The outcome for 75 patients treated with surgery alone (6-year PFS, 89%) was not significantly different from that of 66 patients receiving radiation therapy (6-year PFS, 94%). There was no significant difference between 40 patients with gross or microscopic residual disease treated with surgery alone (PFS, 92%) and 59 patients with residual disease who also received radiation (PFS, 90%). Five of seven patients who progressed after surgery alone have been salvaged with further therapy and are now free of disease. One survives with disease, so that the 6-year survival is 98% for those treated initially with surgery alone, compared with 95% for those receiving radiation therapy and/or chemotherapy. These data suggest that surgery alone, even if complete resection is not achieved, is sufficient initial therapy for stage II neuroblastoma. The data also identify another stage of neuroblastoma, in addition to stage IV-S, for which almost all patients have a favorable prognosis because their tumor may be biologically limited in growth.

Abdominal Neoplasms↗