Detection of recurrence in childhood solid tumors

Abstract

Tasmanian devil lymphoid tissues (thymus, spleen, and lymph node) from seven animals, including pouch young, juvenile, and adult devils, were investigated using histological and immunohistochemical techniques. Antibodies against the conserved intracytoplasmic portion of CD3 and CD79b (T‐ and B‐cell markers, respectively) and MHC II were used to label immune cells. The thymus from the juvenile devils and the pouch young had CD3+ cells that were primarily located in the medulla of the organ. The spleen consisted of red and white pulp areas with characteristic lymphoid follicles with CD79b+ and MHC II+ cells and nonfollicular T‐cell‐dominated periarteriolar lymphoid sheaths. Peripheral lymph nodes presented three distinct regions, outer cortex and medulla (both with primarily CD79b+ and MHC II+ cells) and paracortex (mainly CD3+ cells). Tissue architecture and distribution of the immune cells were similar to that seen in eutherian mammals and other marsupials, indicating that the Tasmanian devil has all the structural elements necessary for effective adaptive immunity. Anat Rec, 292:611–620, 2009. © 2009 Wiley‐Liss, Inc.

Pediatric brain tumor cancer stem cells: cell cycle dynamics, DNA repair, and etoposide extrusion

“…4 Although there have been some improvements in the outcome for children with brain tumors, 5 the prognosis for children with high grade or diffuse intrinsic pontine gliomas, relapsed medulloblastoma, and ependymoma is extremely poor. 6,7 In order to achieve the necessary delicate balance between improved treatment and avoidance of damage to the developing brain, we need a better understanding of the underlying biology of these tumors.…”

Oncological imaging: tumor surveillance in children

“…The usefulness of ongoing surveillance imaging remains controversial [9, 12, 13, 17] Chong et al [18] recently reported on the radiation exposure burden placed on survivors of various cancers. Five-year cumulative estimates of individual radiation exposures were calculated to range from 10 mSv to 642 mSv (median, 61 mSv) resulting from 690 imaging procedures.…”

“…They further pointed out that routine scheduled surveillance appointments failed to detect half of the relapse cases they report [12]. Similarly, Howell et al [17] reported 37 recurrences of solid tumors in a cohort of 186 pediatric patients followed for a median of almost 6 years. More than half of the recurrences were symptomatic.…”

“…More than half of the recurrences were symptomatic. They further estimated that for every recurrence, 42 routine MR examinations, 129 CT examinations and 257 chest radiographs were performed [17]. …”

“…Not only must the potential impact of repeated exposures to ionizing radiation be considered [31–37] but also the potential impact of repeated contrast administration, anesthesia risks [8, 38], costs of time, resources and funds [8, 9, 11, 17] and the impact of false-positive and false-negative findings.…”