Rhabdo

Question 1

what fusion mutations are found in ARMS

Answer 1

PAX-FOXO1 (usually PAX3 or PAX7)

Question 2

most common fusion protein in ARMS

Answer 2

PAX3-FOXO1

T(2;13) in 60% of ARMS

Question 3

2nd most common fusion protein in ARMS

Answer 3

PAX7-FOXO1

t(1;13) in 20% of ARMS

Question 4

what is fusion negative RMS

Answer 4

do not have PAX3 or PAX7-FOXO1 (ERMS, spindle cell, botryoid RMS)

Question 5

Genetic abnormalities in ERMS

Answer 5

Aneuploidy
RAS pathway activating mutations
p53 mutations
LOH 11p15.5 (enhanced IGF2 expression)

Question 6

most common primary sites in RMS

Answer 6

head/neck
GU
extremity

Question 7

syndromes associated with RMS

Answer 7

LFS
Beckwith-Wiedemann
Costello
Noonan
NF1
Gorlin
Dicer1

Question 8

Staging of RMS

Answer 8

MRI/CT of primary and regional nodes, CT chest, PET scan, bilateral bone marrow asp/biopsy, CSF if paramengingeal tumours, retroperitoneal LN assessment for paratesticular > 10 yrs or extremity RMS

Question 9

favourable sites in RMS

Answer 9

orbit, non-parameningeal H+N, non-bladder/prostate GU, biliary tract

Question 10

stage 1 RMS

Answer 10

localized tumour in favourable site

Question 11

stage 2 RMS

Answer 11

unfavourable primary site, but small (=< 5cm) without node involvement

Question 12

stage 3 RMS

Answer 12

unfavourable primary, localized but can be large

Question 13

stage 4 RMS

Answer 13

all with distant mets

Question 14

RMS grouping is based on what?

Answer 14

extent of resection before any therapy given

Question 15

group III RMS

Answer 15

tumour biopsied but no surgical resection performed

Question 16

prognostic factors for RMS

Answer 16

fusion status (fusion negative > fusion positive), histology, stage, group, age, metastatic disease, recurrent disease

Question 17

morphology of ERMS vs ARMS

Answer 17

ERMS: spindle cell tumour
ARMS: small round blue cell tumour

Question 18

RMS immunohistochemical stain

Answer 18

MyoD, Myogenin, Desmin, Muscle specific actin

Question 19

growth pattern of botryoid tumours

Answer 19

grape-like, usually occurs in hollow organ like vagina or nasopharynx

Question 20

spindle cell RMS - how common? outcome?

Answer 20

5-10% of cases

favourable prognosis

Question 21

how common is fusion negative ARMS?

Answer 21

20% of ARMS

Question 22

which sites require surgical assessment of LNs?

Answer 22

• paratesticular (> 10 yrs for RPLNA)

- extremity

Question 23

where does RMS recur?

Answer 23

2/3 are local recurrences

Other: lung, bone, bone marrow

Question 24

how do you decide RT field for RMS

Answer 24

determined by pre-treatment tumour size

Question 25

treatment for intermediate risk RMS

Answer 25

VAC/VI x 45 weeks

Question 26

treatment for low stage, low risk ERMS

Answer 26

VA +/- lower cyclophosphamide dose or shorter duration therapy

Question 27

treatment for high risk RMS

Answer 27

standard therapy not defined

Question 28

what is maintenance therapy and in what group can you consider it

Answer 28

vinorelbine/cyclophos x 6 months for IR patients

Question 29

what do you do about residual masses after tx for RMS?

Answer 29

can be scar - may be followed without further tx

Question 30

what type of RMS is associated with LFS?

Answer 30

typically embryonal histology with anaplasia