A model for preservation of thymocyte-depleted thymus

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

Treatment results of three consecutive Brazilian cooperative childhood ALL protocols: GBTLI-80, GBTLI-82 and -85. ALL Brazilian Group

The Brazilian Cooperative Group for Treatment of Childhood Acute Lymphocytic Leukemia (GBTLI) has started clinical activities trials in 1980. Three consecutive multicenter studies in children with unprevious treated ALL have been completed including 994 patients. The first GBTLI-80 accrued 203 children from 1980 to 1982. It was delineated with the standard three drugs induction therapy, CNS protection for all pts comprised cranial irradiation and intrathecal Methotrexate. For low risk pts cranial irradiation with 18Gy was compared in a randomized trial with 24Gy. Maintenance therapy continued for 120 weeks. The 12 years of the event free survival rates for all risk groups is 50% (SD 5%). Regarding CNS relapses there was no significant statistical difference between pts that received 18 or 24Gy. The treatment strategy of GBTLI-82 (n = 360) from 1982 to 1985, consisted of the same previous induction, consolidation, CNS therapy with cranial irradiation 18 Gy (low risk) or 24Gy (high risk), followed by continuous maintenance for 2 years. The main question in this study was the comparison between sequential rotation or pulses of 3 pairs of drugs during maintenance. At a median follow-up of 10 years, the overall event free survival rates for all children is 58% (SD 4%). There was no significant difference between the two maintenance regimens. The successor GBTLI-85 ran from 1985 to 1988 and registered 431 pts. For the first time no cranial radiation was given to children with very good prognosis. For them, CNS protection was done with triple intrathecal therapy during all treatment. A consolidation therapy with high dose ARA-C was introduced for high risk pts and infants The 6.5 years event free survival for all children is 70% (SD 4%). Significant better results were achieved for high risk and infants pts (EFS 50%). Early intensification therapy and rotational combination chemotherapy improved the outcome in childhood ALL in Brazil.

Poland's syndrome associated with childhood non-Hodgkin's lymphoma

Poland's syndrome is a congenital absence of the sternal portion of the pectoralis major muscle, often associated with ipsilateral upper-limb anomalies. We describe two children with non-Hodgkin's lymphoma associated with Poland's syndrome, ie, an association between childhood cancer and congenital anomalies previously unreported and unlikely to be due to chance. In addition, we report another case of acute leukemia in a child with Poland's syndrome. In view of the rarity of Poland's syndrome in the general pediatric population, we conclude that there is an increased association of the syndrome with both leukemia and non-Hodgkin's lymphoma, the biologic basis of which is unclear.

The natural history of colorectal carcinoma in adolescents

The symptoms, histology, extent, and course of disease of 24 adolescents with colorectal carcinoma who were admitted to St. Jude Children's Hospital between 1964 and 1980 are presented. Twenty of the patients were referred between October 1974 and June 1980. Most patients presented with vague abdominal complaints. Twenty-one of the 24 patients had poorly differentiated mucin-producing adenocarcinoma. Extensive disease at diagnosis and unresponsiveness to medical management was reflected in the eight-month median survival from diagnosis. Only two of the 24 patients survive free of disease 15 and 130 months from diagnosis. Two other patients survive with disease at four and 24 months.