RMS Flashcards
RMS
General Treatment Paradigm for RT
Group IV (distant metastases) -any nodal status/molecular subtype
Treat primary as (group I-III) + other sites of metastatic disease
Ongoing Investigations:
Treating bone metastases with stereotactic body radiation therapy.
RMS
General Treatment Paradigm for RT
Group III (gross residual disease) -any nodal status/molecular subtype
50.4 Gy.
Ongoing Investigations:
For patients with group III disease, treating the prechemotherapy volume to 36 Gy followed by a boost to 50.4 or 59.4 Gy if the initial size is >5 cm.
RMS
General Treatment Paradigm for RT
Group II (positive microscopic margins or resected regional disease)
node +
41.4 Gy
Ongoing Investigations:
Reducing the dose to 36 Gy for patients with group II node-positive disease.
RMS
General Treatment Paradigm for RT
Group II (positive microscopic margins or resected regional disease)
node (–)
36 Gy
RMS
General Treatment Paradigm for RT
Group I (localized disease, completely resected with negative margins)
fusion-negative
No RT
RMS
General Treatment Paradigm for RT
Group I (localized disease, completely resected with negative margins)
fusion-positive
36 Gy
RMS
What are the most common locations of RMS (in decreasing incidence)
genitourinary (31%) parameningeal (25%) extremity (13%) orbit (9%) retroperitoneum (7%) head and neck (7%) trunk (5%) others (3%)
GP E ORTHO
RMS
RMS is more common in blacks than in whites.
TRUE or FALSE?
False
annual
incidence of 4.4 per 1 million whites and 1.3 per 1 million blacks
RMS
RMS is more common in males than females;
males may have slightly worse OS.
TRUE or FALSE?
False (due to second statement)
The male-tofemale
ratio is approximately 1.5 to 1.0, and males may have slightly better
overall survival
RMS
RMS has 2 peak age frequencies.
2 to 6 and in adolescence.
What is the most common histology for patients in the younger group?
embryonal
RMS
RMS has 2 peak age frequencies.
2 to 6 and in adolescence.
What is the most common histology for patients in the older (≥10) group?
alveolar
RMS
Age is an independent predictor of prognosis, with children <1 and >10 years having inferior survival.
TRUE or FALSE?
true
Adults with RMS have been reported to have poor
outcomes, although there is evidence that when they are treated aggressively
using pediatric-type protocols, the prognosis may be similar to that of younger
patients.
true
What is the fusion status important in prognostication and therapeutic decision-making in RMS?
PAX/FOXO1 fusion status
What is the most common histology of urinary or vaginal RMS?
botryoid / embryonal
Urinary or vaginal RMS is common to what age group?
infants
What is the most common location/histology of adolescent RMS?
trunk and abdominal
alveolar
In RMS, what are the predictors of lymph node involvement aside from tumor location?
large tumor size
tumor invasiveness
In RMS, hematogenous dissemination occurs in approximately 15% of disease at presentation.
What are the most common sites of dissemination?
lungs
bone marrow
bone
The clinical grouping classification used extensively by the Intergroup Rhabdomyosarcoma Study Group (now known as the Children’s Oncology Group Soft Tissue Sarcoma [COG STS] committee) investigators is somewhat of a misnomer because it actually requires surgical pathologic evaluation.
What is its importance?
for treatment selection
In RMS, if the IRS study group classification is used for treatment selection, what is used for prognostication?
TNM
RMS
What are the parameters of the TNM that correlates with good prognosis?
non invasiveness
small size
absence of metastases
site of tumor
RMS
IRG grouping:
Incomplete resection or biopsy with gross residual disease
Group III
RMS
IRG grouping:
Localized disease, completely resected
Infiltration outside organ or muscle of origin; regional nodes not involved
Group IB
RMS
IRG grouping:
Localized disease, completely resected
Confined to organ or muscle of origin
Group IA
RMS
IRG grouping:
Compromised or regional resection
Regional disease with involved nodes, grossly resected, but with evidence of
microscopic residual disease
Group IIC
RMS
IRG grouping:
Compromised or regional resection
Grossly resected tumor with microscopic residual disease
Group IIA
RMS
IRG grouping:
Compromised or regional resection
Regional disease, completely resected, in which nodes may be involved or extension
of tumor into adjacent organ may exist
Group IIB
RMS
Favorable sites
orbit
H&N (non parameningeal)
GU (non-bladder/prostate)
RMS
Unfavorable sites
bladder/prostate
parameningeal
extremity
other
RMS
Staging
T1
confined to organ
RMS
Staging
T2
extension outside site or organ of origin
RMS
Staging
a
≤5 cm
RMS
Staging
b
5 cm
RMS
Staging
Identify the stage:
Favorable, N0, T1a, M0
I
RMS
Staging
Identify the stage:
Unfavorable, N0, T1a, M0
II
RMS
Staging
Identify the stage:
Favorable, N1, T1a, M0
I
RMS
Staging
Identify the stage:
Favorable, N0, T1b, M0
I
RMS
Staging
Identify the stage:
Unfavorable, N0, T2a, M0
II
RMS
Staging
Identify the stage:
Favorable, N1, T1b, M0
I
RMS
Staging
Identify the stage:
Unfavorable, N0, T1b, M0
III
RMS
Staging
Identify the stage:
Favorable, N1, T2b, M0
I
RMS
Staging
Identify the stage:
Unfavorable, N0, T2b, M0
III
RMS
Staging
Identify the stage:
Favorable, N1, T2a, M0
I
RMS
Staging
Identify the stage:
Unfavorable, N1, T1a, M0
III
RMS
Staging
Identify the stage:
Unfavorable, N1, T1b, M0
III
RMS
What histologies are considered to be in the superior prognosis group?
botryoid - commonly in vagina, urinary bladder, middle ear, biliary tree, and nasopharynx.
spindle - commonly in paratesticular
RMS
What histology is considered to be in the intermediate prognosis group?
embryonal - commonly found in orbit, head and neck, and genitourinary sites
RMS Histology
Identify:
- a polypoid variant of embryonal RMS
- has a grapelike appearance
- stroma consists of loose cellular tissue with a myxoid appearance.
Under the superficial stroma is a hypercellular zone of tumor cells called the cambium layer of Nicholson.
botryoid
RMS Histology
Identify:
- consists of blastemal mesenchymal cells that tend to differentiate into cross-striated muscle cells.
- have eosinophilic cytoplasm, which is positive by periodic acid–Schiff staining.
- actin- or desmin-positive reactions.
- evidence of myogenesis with the presence of thick and thin cytoplasmic intermediate filaments or Z-band material.
Ribbon or strap-shaped cells and tadpole cells are characteristic.
The presence of cross-striations confirms the diagnosis.
embryonal - commonly found in orbit, head and neck, and genitourinary sites
RMS
What is the genetic abnormality in the embryonal subtype?
consistent loss of heterozygosity at the chromosome 11p15.5 locus
RMS
What histologies are considered to be in the poor prognosis group?
alveolar - commonly found in adolescents with truncal, retroperitoneal,
and extremity tumors
anaplastic
undifferentiated
RMS Histology
Identify:
Approximately 75% of children with this histology exhibit a characteristic translocation involving chromosomes 2 and 13, t(2;13)(q35;q14), and occasionally a 1;13 translocation.
These translocations correspond to abnormal fusion genes involving PAX3-FKHR and PAX7-FKHR, respectively, and are probably the initial oncogenic events in these tumors.
Immunohistochemical presence of AP2-β and P-cadherin is also highly specific for this histology.
alveolar
RMS
orbital RMS
What is the role of surgery?
histologic confirmation only for initial treatment
and as a salvage exenteration and enucleation for management of posttreatment ocular complications
RMS
orbital RMS
What is the primary treatment?
chemo with VAC or VA
vincristine, actinomycin-D, cyclophosphamide
RMS
orbital RMS
(from inservice bank)
When is RT administered after chemotherapy?
after 12 weeks
RMS
orbital RMS
RT dose?
50 Gy.
45 Gy is associated with unacceptable local control rates
D9602 and ARST0331
RMS
What sites are considered parameningeal?
nasopharynx paranasal sinuses middle ear pterygopalatine fossa infratemporal fossa
RMS
What RT technique is used for parameningeal RMS with meningeal dissemination?
CSI
RMS
What RT dose is given for the primary parameningeal tumor as definitive treatment?
50.4/28
RMS
What is the role of RT for nonparameningeal H&N tumors?
PORT
RMS
Gynecologic
What is the most common site?
Vagina
RMS
Gynecologic
Treatment
Surgery + RT +/-chemotherapy
RT for all microscopic or macroscopic tumor.
analysis of data
from the IRS-IV and IRS-V studies have revealed high rates of local failure for
vaginal tumors when local control with surgery or radiotherapy is omitted
RMS
Extremity
Treatment
avoid disfiguring surgical procedures and recommend limb-salvage procedures including irradiation and chemotherapy
RMS
Extremity
RT of involved lymphatics is mandatory
TRUE or FALSE?
True
RMS
RT
CTV?
prechemo volume + surgical sites and biopsy tracts
+ 1 cm
RMS
RT
cone-down volume after microscopic dose has been delivered.
gross posttreatment volume
RMS
RT
Dose for gross residual disease?
standard: 50.4/1.8/28
hfrt: 59.4/1.1 bid
RMS
RT
Dose for microscopic residual disease associated with a lymph node involvement?
41.4 Gy
RMS
RT
Dose for microscopic residual disease “not” associated with a lymph node involvement?
36 Gy
RMS
Which IRS study/studies introduced and omitted WBRT for patients with parameningeal tumors?
II and (III-IV) respectively
III for with intracranial
IV for all patients
