Annual Meeting Proceedings Part 1 - American Society of Clinical ...

622s Pediatric Oncology
9565 General Poster Session (Board #42D), Sun, 8:00 AM-12:00 PM
Circulating myeloid-derived suppressor cells in pediatric solid tumor
patients. Presenting Author: John M. Goldberg, University of Miami Miller
School of Medicine, Miami, FL
Background: Cure rates have reached a plateau for many pediatric solid
tumors. Identifying new therapeutic targets, biomarkers of response and
prognostic indicators should improve clinical outcomes. Accumulation of
myeloid derived suppressor cells (MDSCs) is an important mechanism of
tumor mediated immune evasion. Increased levels of MDSCs in adult
cancer patients correlate with a worse prognosis, and decrease in levels
with treatment is associated with benefit. Little is known about MDSCs in
childhood, or in children with cancer. This pilot measured levels of MDSCs
in pediatric patients with cancer and healthy children. Methods: We
enrolled subjects using an Institutional Review Board approved protocol
after obtaining informed consent. Blood was obtained from 14 children
with newly diagnosed or recurrent solid tumors at start of therapy. In 10 of
these patients, levels were also drawn after therapy. Blood was obtained
once from 6 healthy children in a primary care office. Samples were
obtained concurrently with complete blood counts. MDSCs were measured
on fresh whole blood and were defined as Lin-1�/HLADR-/CD 33�/
CD11b�/ by flow. Total MDSC numbers were then calculated. Results: The
mean total number of MDSCs was 596 cells/ul at diagnosis for the 14
children with cancer and 170 cells/ul for the 6 healthy children (t(18) �
3.02, p � .0073). For the 10 children with cancer who had repeat values
measured after treatment, MDSCs decreased in 4 and increased in 6. The
mean initial MDSC count for these children was 494 cells/ul, and the mean
post treatment count was 1716 cells/ul (t(9) � 1.81, p � .1036). Larger
change scores tended to be associated with children treated with alkylator
therapy followed by G-CSF. The results for percent MDSC in white cells
mirrored those of total number. Conclusions: Circulating MDSCs were
higher in pediatric cancer patients than healthy controls. Cancer treatment
did not reliably reduce MDSC levels. After some treatments, the levels
increased, potentially increasing immune tolerance. Further research is
needed to determine if circulating MDSCs are a reliable predictive or
prognostic marker in pediatric cancer, and whether they represent a
potential target for therapeutic intervention.
9567 General Poster Session (Board #42F), Sun, 8:00 AM-12:00 PM
Diffuse pontine gliomas in children: Do changing strategies change results?
Presenting Author: Rejin Kebudi, Istanbul University, Cerrahpasa Medical
Faculty and Oncology Institute, Istanbul, Turkey
Background: The prognosis of children with diffuse intrinsic pontine
gliomas (DIPG) is dismal. Despite various studies undertaken to improve
outcome, radiotherapy (RT) remains the standard treatment, which is
mostly palliative. This study aims to evaluate characteristics and treatment
outcome of children with DIPG in a single center. Methods: We retrospectively
reviewed the demographic, clinical characteristics and treatment
outcome of children with DIPG treated at Istanbul University, Oncology
Institute from 1999 to 2011. We also evaluated the group that prospectively
recieved RT with concurrent and adjuvant temozolamide after 2004.
Results: 47 children (24 female, 23 male) with the median age of 7 years (6
months-16 years) were analyzed. The median duration of symptoms was 30
days (2-630 days). The frequent clinical findings were ataxia, strabismus
and motor weakness. All patients received RT, 54-60 Gy to the tumor site.
12 recieved only RT. 35 had concomitant and/or adjuvant chemotherapy
with RT. 8 recieved cisplatinum, 7 vincristine. Since 2004, 20 patients
recieved the institutional protocol consisting of temozolomide (TMZ) (75
mg/m2/day) for 6 weeks concurrent with RT, followed by TMZ (200
mg/m2/day) for 5 days every 28 days for 12 cycles or until progression.
There was no major side effect due to TMZ, thrombocytopenia being the
most frequent, but managable side effect. The median overall survival after
diagnosis was 13 months (3-132 mo.) for the whole group. The median
overall survival in 20 patients that received RT and TMZ [ 17 months
(3-132 months)], was significantly superior than that in 12 patients that
recieved only RT [ 12 months (3-20 months)] ( (p�0.03). Nimotuzumab
was given to 4 patients that progressed after RT and TMZ. There was no
major side effect due to nimotuzumab. One was stable for 1 year with
significant clinical improvement, the others were stable for 5, 2 and 2
months after nimotuzumab. Conclusions: In our series, the median survival
was significantly superior in patients who received RT with concurrent and
adjuvant temozolamide in comparison to patients that recieved RT alone.
Nimotuzumab may be promising in some progressive patients, its role as
upfront treatment needs further investigation.
9566 General Poster Session (Board #42E), Sun, 8:00 AM-12:00 PM
Intensive alternating 6-drug chemotherapy for high-risk nonmetastatic
rhabdomyosarcoma in children and adolescents: Impact on survival.
Presenting Author: Gerges Attia Demian, National Cancer Institute, Cairo
University, Cairo, Egypt
Background: Both 5-year overall survival (OS) and event free survival (EFS)
for pediatric rhabdomyosarcoma (RMS) has increased in the last 3 decades
through multimodality, risk-adapted management. The reported EFS for
high risk RMS in children treated at the NCI in Egypt during the 1990s was
50%. Using an intensive 6 drug alternating chemotherapy regimen in
addition to local control measures was our aim to improve the outcome for
this group of patients. Methods: Forty-six previously untreated patients,
younger than 21 years of age, with localized high risk RMS received this
regimen. High risk criteria included: (1) Localized tumors (T1) biopsied or
incompletely resected, ortumors extending beyond the tissue or organ of
origin (T2) completely or incompletely resected at any site (excluding orbit,
uterus, vagina, and paratestis); (2)All node positive patients with primary
tumor at any site; and (3) All RMS with alveolar histology at any site.
Chemotherapy regimen comprised 27 weeks of alternating 6 drugs (carboplatin,
doxorubicin hydrochloride, ifosfamide, actinomycin D, etoposide,
vincristine). Local therapy (surgery, radiotherapy, or both) was offered at
week 9. Results: Forty-six patients meeting high-risk criteria were recruited
from September 2000 to November 2005. Median follow-up of survivors
was 62 months. The 5-year OS and EFS for the whole group was 64% �
10% and 47% � 8% respectively. The EFS was significantly affected by:
the size of the tumor (�5 cmvs.� 5 cm, p� 0.03), SIOP UICC clinical
stage (p � 0.004), IRS stage (p � 0.01), lymph node status (p � 0.02),
surgery vs. incisional biopsy (p�0.01) and overall duration of time in which
therapy was delivered (p � 0.04). There was significant toxicity, mainly
hematologic, but only one treatment related fatality. Conclusions: The use
of intensified alternating 6-drug CT did not improve the EFS compared with
historical control although it was feasible to be delivered safely in a variety
of outpatient settings. Surgical resection of the tumor is essential.
Delivering therapy in a timely fashion appears to impact outcome and
future investigations will focus on impediments to administering chemotherapy
as scheduled.
9568 General Poster Session (Board #42G), Sun, 8:00 AM-12:00 PM
Demographics, treatment, and outcome of retinoblastoma: A large series
with protocol-based management. Presenting Author: Vijay Anand Palkonda
Reddy, Apollo Hospitals, Hyderabad, India
Background: Retinoblastoma is the most common primary intraocular
malignancy of childhood with incidence of 1 in 20,000 and the third most
common pediatric cancer. In the previous decades, early diagnosis and
treatment of retinoblastoma have improved survival rates in developed
countries. Nevertheless, protocol based management help reduce the
mortality rate associated with advanced tumors. The purpose of the study is
to report demographics, management, and outcome of retinoblastoma in
the Ocular oncology centre of South India. Methods: Consecutive case
series of 1,543 eyes of 1,067 patients with 22 years of follow-up.
Demographics, clinical features, treatment and outcome (survival, organ
salvage and function salvage) were analyzed. Management comprised of
focal therapy for small tumors, standard triple drug chemoreduction for
larger (�4mm) tumors, high dose chemoreduction and periocular chemotherapy
for vitreous seeds, and enucleation for advanced tumors. Adjuvant
therapy was provided in patients with histopathologic high-risk factors for
systemic metastasis. Orbital retinoblastoma was managed with a multimodal
treatment protocol. Results: Sixty-six percent were �3 years of age.
Forty-five percent were bilateral. Symptoms were leucocoria (33%), vision
loss (10%), proptosis (6%), and squint (6%). The tumor was intraocular in
94% and orbital in 6%. Management was by protocol and included
enucleation (52%), chemoreduction (26%), focal therapy (11%), and
external beam radiation (5%). Fifty-five percent of enucleated patients had
histopathologic risk factors for metastasis and received adjuvant chemotherapy.
Chemoreduction with focal therapy resulted in eye and vision
salvage in 92%. Overall, 94% survived. Conclusions: Protocol-based
management of retinoblastoma provides excellent prognosis for survival,
eye salvage and vision salvage.
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