Rebound Thymic Hyperplasia after Chemotherapy in Children with Lymphoma.

BACKGROUND: Development of mediastinal masses after completion of chemotherapy in pediatric patients with malignant lymphoma is worrisome and challenging to clinicians. METHODS: We performed a retrospective review of 67 patients with lymphoma treated at our hospital from January 1, 2001 to June 1, 2013. Patients who received at least two chest computed tomography (CT) examinations after complete remission (CR) was achieved were further analyzed. Gallium-67 scans and positron emission tomography (PET) were recorded and compared between these patients. RESULTS: Sixty-two of 67 patients reached CR, of whom 31 (22 male, 9 female) were patients that received at least two chest CT examinations after CR. Rebound thymic hyperplasia (RTH) was diagnosed in 21/31 patients (67.7%), including 14/23 (60.9%) and seven out of eight (87.5%) with non-Hodgkin's lymphoma and Hodgkin's lymphoma, respectively. Ages ranged from 3 years to 18 years (median 10 years). Increased radioactivity uptake of the anterior mediastinum in gallium scans was found in nine out of 20 patients (45%) with thymic rebound. PET was performed in six out of 21 patients. Increased fluorodeoxyglucose (FDG)-avid uptake in the anterior mediastinum was observed in four of six patients (66.7%) by PET. One patient received thymectomy. No patients with RTH had lymphoma relapse within the median follow-up period (5 years). Relapse was statistically significantly different (p = 0.001) between patients with and without RTH. CONCLUSION: RTH developed in 67.7% of pediatric patients with lymphoma in CR after chemotherapy. The association of RTH development and lowered relapse rates has yet to be determined. Awareness of this phenomenon is important in the prevention of unnecessary surgical intervention or chemotherapy.

Dislodgement of port-A catheters in pediatric oncology patients: 11 years of experience.

BACKGROUND: Port-A catheters are frequently used in pediatric cancer patients. Their dislodgement is potentially seriously risky although the incidence is not high. We analyzed our 11 years of data to address this important problem. METHODS: From January 2001 to December 2011, 330 port-A catheters of different brands were implanted in pediatric cancer patients. In total, eight children suffered a dislodgement of their catheter. Their ages ranged from four to thirteen years, with a median age of ten. Five patients presented with catheter dysfunction, two presented with a cough and one was identified incidentally during surgery to remove his port. RESULTS: The downstream ends of the dislodged catheters were located in the right atrium (three patients), left pulmonary artery (three) and inferior vena cava (two). Six of the eight catheters were broken at the site of anastomosis to the port and the other two were broken halfway in between. All episodes of dislodgement happened after the chemotherapy regimen was completed. The dislodged catheters were successfully retrieved without complications by transcatheter retrieval using a gooseneck snare. CONCLUSIONS: The dislodgment rate of port-A catheter in our series was 2.4%. Chest X-rays can rapidly detect the problem. Most of the catheters were broken at the site of anastomosis. Earlier explantation of port-A catheters after completing chemotherapy may be considered to avoid the dislodgement of catheters, but this needs to be weighed against the possibility of underlying disease recurrence. However, we should re-examine how long port-A catheters need to be retained after chemotherapy considering the improved cure rate of pediatric cancer.

Pediatric malignant ovarian tumors: 15 years of experience at a single institution.

BACKGROUND: Malignant ovarian tumors in children are relatively rare. We reviewed our 15-year experience to understand their clinical presentations, managements, and prognoses. METHODS: There were 15 children who were diagnosed to have malignant ovarian tumors from January 1994 to June 2009 in our hospital. The presenting symptoms, treatments, and outcomes were obtained retrospectively from the medical records. RESULTS: The median age at presentation was 13 years. The most common presenting symptom was abdominal pain, occurring in 10 patients (66.7%). The tumors were in the left side in 10 patients (66.7%). The pathologic diagnoses were yolk sac tumors in four patients, immature teratomas in four, dysgerminomas in three, malignant mixed germ cell tumors in three, and carcinosarcoma in one patient. According to the Federation Internationale de Gynecologie Oncologique classification, seven girls had Stage I, one had Stage II, and seven had Stage III disease. Thirteen patients received chemotherapy with platinum-based regimens. Three patients died of their disease: one of yolk sac tumor, one of malignant mixed germ cell tumor, and one of carcinosarcoma. They all had Stage III disease at diagnosis. The 10-year overall survival and disease-free survival rates were 77% and 69%, respectively. CONCLUSIONS: Pediatric malignant ovarian tumors were highly curable disease if they were not in the advanced stage at presentation. Earlier consideration of malignant ovarian tumor in the differential diagnosis of young girls with abdominal pain is important.