Utility of frozen section in pediatric and adolescent malignant ovarian nonseminomatous germ cell tumors: A report from the children's oncology group.

PURPOSE: In adult women, most malignant ovarian tumors are epithelial in origin. The use of intra-operative frozen section to distinguish between benign and malignant histology is reliable in guiding operative decision-making to determine the extent of surgical staging required. Pediatric and adolescent patients with ovarian masses have a much different spectrum of pathology with most tumors arising from germ cell precursors. This review was undertaken to assess the concordance between the intra-operative frozen section and the final diagnosis as an aid to guide extent of surgical staging in a group of pediatric and adolescent patients with malignant ovarian germ cell tumors. METHODS: Records of patients aged 0 to 20 years with malignant ovarian germ cell tumors enrolled on Children's Oncology Group study AGCT0132 were reviewed. Pathology reports from patients who had both intra-operative frozen section diagnosis and final paraffin section diagnosis were compared using descriptive statistics. By inclusion criteria for the study, all patients had a final diagnosis of malignancy with required yolk sac tumor, choriocarcinoma or embryonal carcinoma histology. Available central review of pathology final paraffin section slides were compared with final institution pathology reports. RESULTS: Of 131 eligible patients with ovarian germ cell tumors, 60 (45.8%) had both intra-operative frozen section and final paraffin section diagnoses available. Intra-operative frozen section diagnoses were classified as: incorrect diagnosis of benign tumor (13.3%), confirmation of malignancy (61.7%), immature teratoma (16.7%), germ cell tumor not otherwise specified (5%) and no diagnosis provided (3.3%). Intra-operative frozen section was incorrect in 23 of 60 (38.3%) patients evaluated. Central pathology review was concordant with the final institution pathology diagnosis in 76.3% of patients. Central pathology review identified additional germ cell tumor components in 23.7% of patients. CONCLUSIONS: In pediatric and adolescent patients with a confirmed final diagnosis of ovarian germ cell malignancy, intra-operative frozen section diagnosis is not reliable to inform the extent of surgical staging required. Central review by an expert germ cell tumor pathologist provides important additional information to guide therapy.

Outcome and staging evaluation in malignant germ cell tumors of the ovary in children and adolescents: an intergroup study.

PURPOSE: The aim of this study was to perform an evaluation of outcome and the role of surgical staging components in malignant germ cell tumors (GCT) of the ovary in children and adolescents. METHODS: From 1990 to 1996, 2 intergroup trials for malignant GCT were undertaken by Pediatric Oncology Group (POG) and Children's Cancer Study Group (CCG). Stage I-II patients were treated with surgical resection and 4 cycles of standard dose cisplatin (100 mg/m2/cycle), etoposide, and bleomycin (PEB) chemotherapy. Stage III-IV patients were treated with surgical resection and randomly assigned to chemotherapy with PEB or high-dose cisplatin (200 mg/m2/cycle) with etoposide and bleomycin (HDPEB). Patients unresectable at diagnosis had second-look operation after 4 cycles of chemotherapy if residual tumor was seen on imaging studies. IRB approval of the protocols was obtained at each participating institution. An analysis of outcome data, operative notes, and pathology reports in girls with ovarian primary site was done for this report. RESULTS: There were 131 patients with ovarian primary tumors of 515 entered on these studies. Mean age was 11.9 years (range, 1.4 to 20 years). Six-year survival rate was stage, I 95.1%; stage II, 93.8%; stage III, 98.3%; stage IV, 93.3%. In only 3 of 131 patients were surgical guidelines followed completely. Surgical omissions resulting in protocol noncompliance resulted from failure to biopsy bilateral nodes (97%), no omentectomy (36%), no peritoneal cytology (21%), no contralateral ovary biopsy (59%). More aggressive procedure than recommended by guidelines included total hysterectomy and bilateral salpingo-oophorectomy in 6 patients and retroperitoneal node dissection in 10 patients. Correlation of gross operative findings with pathology results was carried out for ascites, lymph nodes, implants, omentum, and contralateral ovary. CONCLUSIONS: Pediatric ovarian malignant GCT (stages I-IV) have excellent survival with conservative surgical resection and platinum-based chemotherapy. Survival appears to have been unaffected by deviations from surgical guidelines. New surgical guidelines are proposed based on correlation of gross findings, histology, and outcome in these intergroup trials.

Malignant retroperitoneal and abdominal germ cell tumors: an intergroup study.

BACKGROUND/PURPOSE: This randomized study examined survival (S) and event-free survival (EFS) rates using high-or standard-dose cisplatin-based combination chemotherapy and surgical resection for this subset of germ cell tumors. METHODS: Twenty-six of 317 patients enrolled on the POG 9049/COG 8882 intergroup study for malignant germ cell tumors had abdomen or retroperitoneum as the primary site. Twenty-five of 26 were eligible for inclusion (n = 25). Patients had biopsy or resection at diagnosis and randomization to chemotherapy including etoposide, bleomycin, and either standard-dose (PEB) or high-dose cisplatin (HDPEB). In patients with initial biopsy, delayed resection was planned. RESULTS: Median age was 26 months. There were 14 girls and 11 boys. There were 3 stage I to II, 5 stage III, and 17 stage IV patients. Surgical management included primary resection in 5, resection after chemotherapy in 13, and biopsy or partial resection in 7 patients. Overall 6-year EFS rate was 82.8% +/- 10.9%, and 6-year survival rate was 87.6% +/- 9.3%. By group, 6-year survival rate was 90.0% +/- 11.6% for PEB and 85.7 +/- 14.5% for HDPEB. Deaths include one from sepsis, one from malignant tumor progression, and one from bulky disease caused by benign components despite response of the malignant elements to chemotherapy. CONCLUSIONS: Malignant germ cell tumors arising in the abdomen and retroperitoneum have an excellent prognosis despite advanced stage in most children. Aggressive resection need not be undertaken at diagnosis, but a concerted attempt at complete surgical removal after chemotherapy is important to distinguish viable tumor from necrotic tumor or benign elements that will not benefit from further chemotherapy.

Enhanced activity of osteoblast differentiation factor (PEBP2alphaA2/CBFa1) in affected sutural osteoblasts from patients with nonsyndromic craniosynostosis.

OBJECTIVE: Nonsyndromic craniosynostosis is characterized by premature closure of one or more cranial sutures in infants. The purpose of this investigation was to evaluate cellular and molecular events that lead to pathogenesis of nonsyndromic craniosynostosis. DESIGN: This study utilized discarded samples of normal and affected cranial sutures from 12 patients (7 boys, 5 girls) with nonsyndromic craniosynostosis. RESULTS: Histological evaluation of affected sutures revealed complete osseous obliteration instead of a zone of connective tissue and osteogenic cells as seen in normal sutures. Although proliferation of normal and affected osteoblasts did not vary substantially, elevated osteocalcin production and increased in vitro bone nodule formation indicated that the differentiation and the bone-forming potential of affected osteoblasts was significantly higher than that of normal cells. We therefore investigated the levels and activity of Cbfa1, a transcription factor that plays an integral role in osteoblast differentiation. Northern blot analysis of messenger RNA from both normal and affected sutural osteoblasts revealed a twofold increase in the expression of Cbfa1 in affected cells. This increase in the level of Cbfa1 transcript correlated with an increase in its transcriptional activity on the osteocalcin gene promoter, as assessed using gene transfer methods. CONCLUSION: Our results indicated that osteoblasts from synostosed sutures exhibit an increased potential for differentiation and bone formation. The increased level and activity of Cbfa1 could play a vital role in the aberrant function of these affected osteoblasts and may explain their altered behavior compared to the normal cells.

Milk of calcium cholelithiasis in children.

Milk of calcium bile is uncommon and occurs mainly in the adult population. The authors report on 2 children, each having a distinct clinical history and presentation, and each with milk of calcium bile/calculi possessing differing chemical composition and highly notable gross morphology. J Pediatr Surg 36:644-647.

The effect of cisplatin dose and surgical resection in children with malignant germ cell tumors at the sacrococcygeal region: a pediatric intergroup trial (POG 9049/CCG 8882).

PURPOSE: This study was designed to evaluate (1) the efficacy of standard or high-dose cisplatin with etoposide and bleomycin and (2) the role of surgical resection in infants and children with malignant germ cell tumors of the sacrococcygeal region (SCT). METHODS: Seventy-four of 317 children presenting to Pediatric Oncology Group (POG)/Children's Cancer Group (CCG) institutions from 1990 through 1996 with malignant germ cell tumors had malignant SCT. There were 62 girls and 12 boys with a median age of 21 months (range, 3 days to 37 months) and median serum alpha-fetoprotein of 35,500 ng/mL. Twelve had undergone resection of a benign SCT as a newborn. Forty-four (59%) had evidence of metastatic disease at time of diagnosis. Presentation by type (Altman classification) was I, 0; II, 2; III, 30; and IV, 42. The initial procedure was biopsy in 45 and resection in 29. Patients were assigned randomly to receive 4 cycles of chemotherapy with etoposide (E) and bleomycin (B) and either high-dose cisplatin (200 mg/m(2) per cycle; HDP) or standard dose cisplatin (100 mg/m(2) per cycle; P). After completion of chemotherapy, 42 of 45 initially treated with biopsy underwent resection. RESULTS: Overall 4-year survival rate is 90% (SE = 4%) and 4-year event-free survival (EFS) is 84% (SE = 6%). Event-free survival data for subgroups of interest are as follows: 4-yr EFS% (SE) P Values Mets (44) 88 (6).48 No Mets (30) 80 (8) HDP EB (37) 89 (6).21 P EB (37) 78 (7) Initial Resection (29) 90 (7).50 Delayed Resection (42) 83 (7) Complete Resection (49) 90 (5).19 CR/PR Partial Resection (22) 77 (10) Biopsy Only (3) 33 (27).005 (3 way) CONCLUSIONS: (1) The current survival rate of malignant sacrococcygeal tumors is excellent even with metastases. (2) Delayed surgical resection is not associated with an adverse outcome. (3) In this subset the treatment comparison was inconclusive however, followed the trend in the overall study of more than 300 children in which the high-dose cisplatin group had superior EFS (P<.05).

Malignant mediastinal germ cell tumors: an intergroup study.

PURPOSE: This review was conducted to determine clinical characteristics and response to therapy in this rare pediatric neoplasm. METHODS: An intergroup Pediatric Oncology Group (POG) 9049/Children's Cancer Study Group (CCG) 8882 randomized trial was conducted to evaluate response rate and survival with chemotherapy using etoposide, bleomycin, and high or standard dose cisplatin for high-risk malignant germ cell tumors at extragonadal sites. For this review, a secondary analysis of clinical and operative findings in patients with primary site in the mediastinum was carried out. RESULTS: Of the 38 children with malignant mediastinal germ cell tumors (MGCT), 36 had sufficient data to be included in this review. Thirty-four tumors were anterior mediastinal, 2 were intrapericardial. Younger patients had respiratory complaints; older patients had chest pain, precocious puberty, or facial fullness. Yolk sac tumor was the only malignant element in girls. Boys had yolk sac tumor in 7, germinoma in 3, choriocarcinoma in 2, and mixed malignant elements in 15. Benign teratoma elements coexisted in 22 patients. Four patients had biopsy and chemotherapy without tumor resection, and only 1 survived. Fourteen patients had resection at diagnosis followed by chemotherapy with 12 survivors. Eighteen patients had biopsy followed by chemotherapy and postchemotherapy tumor resection with 13 survivors. Tumor size in response to chemotherapy for these 18 patients was stable or increased in 6, and decreased in 12 (mean decrease of 57% in greatest dimension). Overall, 26 of 36 patients survived, with a 4-year patient survival rate of 71%+/-10%, and a 4-year event-free survival rate of 69%+/-10%. Ten patients died: 5 of tumor (all boys > or =15 yr), 2 of sepsis, and 3 of second malignancy. CONCLUSIONS: Malignant MGCT is a complex tumor of varied histology with frequent coexistence of benign elements. Lesions often have incomplete regression with chemotherapy alone. Tumor resection may be undertaken at diagnosis or after attempted shrinkage with chemotherapy. Aggressive attempt at complete tumor resection should be offered to all patients even if bulky tumor persists after induction chemotherapy with expectation of a significant salvage rate. Boys > or =15 years may be a high-risk subgroup for mortality from tumor progression.

Characterization and treatment of biliary anastomotic stricture after segmental liver transplantation.

BACKGROUND/PURPOSE: Biliary anastomotic strictures (BAS) after left lateral segment liver transplantation (LLST) may cause graft dysfunction, sepsis, and patient mortality. A review of the authors' experience was performed to better characterize the risk factors and corrective management. METHODS: The medical records of 9 children who underwent a LLST in whom a BAS developed from 1989 to the present were reviewed retrospectively. RESULTS: Seventy-five of 199 liver transplants (38%) at the authors' institution since 1989 have been LLST. BAS developed in 12% of these cases. BAS were diagnosed less than 12 months after transplantation in 4 children (mean, 7.5 months; range, 5 to 11 months) and greater than 12 months in 5 children (mean, 37 months; range, 14 to 72 months). Early strictures (<12 months) were associated with hepatic artery thrombosis (n = 1), and posttransplant bile leak (n = 1) and ducts from segment II and III exiting separately from the left lateral segment (n = 2). The diagnosis of BAS was heralded by episodes of liver biopsy-proven cholangitis in all patients and confirmed radiographically. Seven children underwent successful biliary exploration and revision of the hepaticojejunostomy. Two of these children ultimately required retransplantation secondary to chronic graft rejection. CONCLUSIONS: BAS in LLST are a source of significant morbidity and should be considered in children after LLST who present with cholangitis. Surgical correction is possible in most cases.

Pediatric recipients of three or more hepatic allografts: results and technical challenges.

BACKGROUND/PURPOSE: Children who require a liver transplant at an early age risk chronic allograft rejection (CAR) and other causes of allograft loss. Multiple retransplants may be required for long-term patient survival. The authors evaluate this approach based on our results and technical difficulties. METHODS: Charts of 7 children who received 3 or more liver transplants from 1989 to the present were reviewed retrospectively. RESULTS: A total of 151 children required liver transplantation at our institution since 1989. Of these, 4 boys and 3 girls (mean age, 6.2 years; range, 3 to 14 years) have received 3 or more allografts. The etiology of liver failure for the penultimate allograft was CAR (n = 6) and hepatic artery thrombosis (HAT; n = 1). Five cases required modification of portal vein or hepatic artery anastomoses. Two patients with vena caval strictures required supradiaphragmatic vena caval reconstruction. The original Roux-en-Y limb was adequate for biliary reconstruction in all cases. Five children currently are alive (survival rate, 71%) with good graft function having had a mean follow-up of 23 months (range, 2 to 48 mos.). CONCLUSIONS: The operative procedure for the multiple hepatic transplant child is challenging. The transplant team must be prepared for intraoperative issues such as extended organ ischemia time during hepatectomy, extensive blood loss, and potential need for creative organ revascularization techniques. Overall, multiple retransplant results are good and justify the use of multiple allografts.

Germ cell, mesenchymal, and thymic tumors of the mediastinum.

Germ cell, mesenchymal, and thymic tumors of the mediastinum are an uncommon and heterogeneous group of neoplasms. Together they account for less than 25% of mediastinal tumors in childhood. The majority of these tumors are found in the anterior and superior mediastinum, but germ cell tumors and mesenchymal tumors may be located in all compartments. They share a broad range of histological subtypes and clinical behavior, tendency to be large in size, and a requirement for complete surgical excision as the major requirement for successful therapy.

Total eyelid reconstruction with free dorsalis pedis flap after deep facial burn.

A case of severe facial and corneal burns with complete loss of upper and lower eyelids is reported together with the acute management and surgical options for total eyelid defects secondary to thermal injury. An acutely burned man with 78 percent total burn surface area presented with complete exposure of the left cornea. Because of the severe thermal injury, no facial tissues were available as donor sources for reconstructing the eyelid. A free dorsalis pedis flap was used to cover the exposed cornea after bilateral conjunctival advancement flaps, with septal cartilage graft for structural support. A conjunctivodacryocystorhinostomy was performed at the time of the coverage. The patient was unable to perform an exact visual acuity test; however, his gross vision was intact.

Transplantation for acute hepatic failure in children.

BACKGROUND/PURPOSE: Acute liver failure in the pediatric population is a rare but highly lethal health problem. Sometimes it is difficult to predict who will benefit from liver transplantation. The authors report on their experience in the past 8 years at a pediatric transplant center. METHODS: A retrospective chart review was performed on all children referred to the liver transplant (TX) service with the diagnosis of acute hepatocellular dysfunction (AHD) from 1988 to 1996. Presentation, chemistries, and clinical course were evaluated. Statistical analysis was performed using analysis of variance. RESULTS: Twenty-six children underwent evaluation. Seventeen patients fulfilled the criteria for fulminant hepatic failure (FHF). Eleven patients recovered without TX, 14 received a TX, and one died awaiting TX. Of those that received a TX, four died in the early postoperative period and 10 survived (mean follow-up of 4.2 years). There was a wide range in most laboratory values. Serum bilirubin levels, ammonia levels, and coagulation parameters, however, reached statistical significance in patients requiring transplant. The most consistent discriminators of need for transplantation and outcome were neurological findings and multisystem organ failure. Children who recovered without TX had no seizures and minimal encephalopathy. Of the 15 children who were recommended for TX, six had seizures and all had encephalopathy, 12 having grade III or IV. All five nonsurvivors had respiratory failure early in their clinical course, and four of five nonsurvivors also had renal failure. CONCLUSIONS: There is significant overlap in the presentation and laboratory findings of children who present with AHD or FHF. Neurological status was an important discriminator of need for transplantation. Patients who presented with multisystem organ failure, including renal failure and respiratory failure, had 100% mortality rate despite liver transplantation.

Gastrointestinal perforation after pediatric orthotopic liver transplantation.

PURPOSE: The aim of this review was to determine the incidence of gastrointestinal perforation after pediatric liver transplantation and to identify risk factors and clinical indicators that may lead to an earlier diagnosis. METHODS: A retrospective chart review of all children who presented with gastrointestinal perforation after liver transplantation at our institution between January 1, 1987 and August 1, 1996 was performed. RESULTS: One hundred fifty-seven orthotopic liver transplants were performed in 128 children. Fifty-eight reexplorations, excluding those for retransplantation, were performed in 38 children. Ten perforations occurred in six children (incidence, 6.4%). Two children required multiple reexplorations because of several episodes of perforation. The sites of perforation were duodenum (n=1), jejunum (n=8), and ileum (n=1). A single-layer closure was used to repair five perforations, two-layer closures in four, and resection with primary anastomosis in another. The type of repair did not affect the occurrence of subsequent perforations. All the children were less than 18 months old. Four children had undergone prior laparotomy. All children had choledochoenteric anastomoses, but only one had a perforation associated with it. One child sustained bowel injury during the dissection for the liver transplant, but none of the perforations occurred at this site. Bowel function had returned before perforation in five children. Five children were receiving systemic antibiotics at the time of their perforation, and none had been dosed with pulse steroids for rejection. All of the children had significant changes in their temperature. Acute leukopenia developed in one child. A leukocytosis developed in the rest of the children. Abdominal radiographs demonstrated pneumoperitoneum in only one child. All children had positive culture findings from their abdominal drains. Cytomegalovirus developed in one child. Although the diagnosis of gastrointestinal perforation after pediatric liver transplant remains difficult, positive drain culture findings and significant alterations in temperature and leukocyte counts suggest its presence. Pneumoperitoneum is rarely present. CONCLUSION: A high index of suspicion and timely laparotomy, especially in children less than 2 years of age, may be the only way to rapidly diagnose and treat this potentially devastating complication of liver transplant.

Transpalatal approach for the extracranial surgical repair of transsphenoidal cephaloceles in children.

The surgical treatment of transsphenoidal cephaloceles in children is controversial. Reduction and repair via a transcranial approach are associated with high postoperative rates of morbidity, mortality, and hypothalamic dysfunction. In this study, four patients, aged 3 to 35 months at surgery, underwent successful transpalatal repair of two encephaloceles and two meningoceles. Two patients presented with nasal obstruction in infancy, one presented with unexplained meningitis, and in one patient the lesion was found incidentally during evaluation for seizures. Two children had median cleft face syndrome, another had an associated Arnold-Chiari type I malformation, and the fourth had no other cranial abnormalities. All patients underwent preoperative evaluation including magnetic resonance (MR) imaging. Auditory, ophthalmological, genetic, endocrinological, or other evaluation was undertaken as indicated. Lesions were approached through the median raphe of the hard and soft palates. All cephaloceles were easily visualized and dissected after division of the nasal palatal mucosa. The dural sac and its contents were reduced by surface coagulation after division and dissection of the overlying mucosa. Once reduced, the bone defect was obliterated in three of four patients. The dura was not opened and anomalous neural elements were not resected. At follow-up evaluation, all patients demonstrated resolution of preoperative symptoms without evidence of infection or lasting morbidity. Follow-up MR imaging showed reduction in all cases. The authors conclude that this transpalatal approach is safe and reliable for the treatment of transsphenoidal cephaloceles in young children.

Fibrosing colonopathy in children with cystic fibrosis.

PURPOSE: Fibrosing colonopathy is a newly described entity seen in children with cystic fibrosis. The radiological hallmarks are foreshortening of the right colon with varying degrees of stricture formation. High-dose enzyme therapy has been implicated as the cause of this process. The purpose of this study is to review the author's experience with evaluation and treatment of these patients. METHODS: There are currently 380 patients being treated at our CF center. Fifty-five of these patients have been treated with high-dose enzyme therapy (> 5,000 units of lipase/kg). The medical records of these patients, who are at risk for developing fibrosing colonopathy, were reviewed for the presence of recurrent abdominal complaints, and the work-up and treatment of these symptoms. RESULTS: Chronic complaints of abdominal pain, distension, change in bowel habits, or failure to thrive were present in 24 of the 55 patients treated with high-dose enzymes. So far, 18 of these 24 patients have been evaluated by contrast enema. Thirteen of eighteen have been found to have fibrosing colonopathy characterized by foreshortening and strictures of the colon. Additional findings included focal strictures of the right colon (7 of 13), long segment strictures (5 of 13), and total colonic involvement (1 of 13). Nine patients with the most severe symptoms have undergone colon resection, including five segmental right colectomies, three extended colectomies (ileo-sigmoid anastomosis), and one subtotal colectomy with end-ileostomy. Pathological evaluation has shown submucosal fibrosis, destruction of the muscularis mucosa, and eosinophilia. No postoperative complications or deaths occurred. All nine postoperative patients have noted marked symptomatic improvement. Contrast enema follow-up results are available for six patients, and have documented no recurrent strictures to date. Three of four nonoperative patients have less severe symptoms and are currently being treated conservatively. The other family has refused surgery and the patient is being treated symptomatically. CONCLUSION: High-dose lipase replacement has been implicated as the etiology for FC and was present in all of our patients. Our cystic fibrosis center now routinely limits lipase to 2,500 U/kg per dose. We recommend the use of the contrast enemas to evaluate at-risk patients who have chronic abdominal complaints or who present with recurrent bowel obstruction. Colon resection should be performed in those with clinically and radiographically significant strictures with the expectation of a good outcome.

Split liver transplantation benefits the recipient of the 'leftover liver'.

The division of a single hepatic allograft to create two reduced-size grafts has been reported with decreased graft survival (50%) resulting in decreased enthusiasm for this approach. The authors reviewed their experience with 12 recipients of this procedure to evaluate the outcome of the children electively undergoing transplant with the "leftover liver." A retrospective review of six pairs of children receiving part of one hepatic allograft included donor anatomy, recipient operation, and allograft and patient outcomes. Recipient pairs were selected according to blood type compatibility, medical priority, and size restrictions of the larger right lobe and the smaller left lateral segment. Patient and graft survival were compared with elective and urgent patients undergoing whole or reduced-size transplants. Six donors weighed 71.8 +/- 17.4 kg and were 22.6 +/- 11.0 years of age. Recipients of the right lobe were 11.8 +/- 4.2 years of age and weighed 41.9 +/- 14 kg. Recipients of the left lateral segment were 1.81 +/- 1.1 years of age and weighed 9.85 +/- 1.82 kg. Six patients were initially offered the donor allograft because of their hospitalization, critical illness or waiting time. Six additional patients electively underwent transplantation with the leftover liver. Donor organs were screened for normal arterial anatomy. Division of the allograft was performed on the back table in the falciform groove. Generally the left lateral segment graft received the major portion of the hepatic artery and the right lobe the major portion of the portal vein. Five of six (83%) elective patients, two receiving the right lobe and three receiving the left lateral segment had prompt recovery and left the hospital without surgical complication. One recipient of a right lobe transplant died from primary allograft nonfunction. These results are not different from the outcomes of all elective patients who underwent transplantation with whole or reduced-sized transplants in the same program. The authors conclude that split liver transplantation benefits the stable patient who electively receives the liver leftover after reducing the size of a large donor liver for a critically ill child.

Hyperdiploidy and trisomy 12 in the cystic partially differentiated nephroblastoma.

The karyotype of a cystic partially differentiated nephroblastoma (CPDN) was found to be 51, XY, +7, +8, +12, +13, +17. A review of the literature disclosed three other cytogenetically analyzed CPDNs. As in this case, they were all hyperdiploid. The only chromosomal anomaly common to all four cases was trisomy 12, suggesting this chromosome might have a pathogenetic role. Earlier reports had tentatively attributed this role to chromosome 8.