Name : Dr khalili
Family : Dr khalili
Affiliation :Radiology department,Mofid Hospital,SBMU
Academic Degree : Assistant professor of Radiology
Resident : Hedieh zamini
Gender : Female
Age : 0
new born infant with abdominal distention
A heterogenous 60*43*53 mm soft tissue mass containing fat and calcification and a small cystic area is seen anterior to sacrum with extension to right gluteous muscles,. The mentioned mass has lead to upward displacement of bladder and it 's outlet obstruction and also bilateral hydronephrosis .Another similar predominently cystic mass , containing fat and calcification is seen adjacent to upper pole of right kidney
•low lying neuroblastoma
•low lying rhabdomyosarcoma
•small round blue cell tumour in sacral region
•enteric (tail gut) cyst - for a purely cystic SCT
Discussion (Related Text)
A sacro-coccygeal teratoma (SCT) refers to a teratoma arising in the sacro-coccygeal region. The coccyx is almost always involved
Demographics and clinical presentation
It is the commonest congenital tumour in the fetus and neonate . The incidence is estimated at ~ 1:35000-40000. There is recognised female predilection with a M : F ratio of 1 : 4. The sacrococcygeal region is also the commonest location for non CNS teratomas. A location based classification system according to the American Academy of Pediatric Surgery Section Survey is:
•type I - developing only outside the fetus (can have small pre-sacral component) ; accounts for the majority of cases : 47% 12.
•type II - extra-fetal with intra-pelvic pre-sacral extension
•type III - extra-fetal with abdomino-pelvic extension
•type IV - tumour developing completely in the fetal pelvis
Not part of routine investigation. Identifies bone, fat and cystic components. Calcification may again be seen.
Mature types tend to be more cystic which show as anechoic components. Solid types (which are much rarer) often show an echogenic mass within the pelvis.
The correlation between sonographic appearances and malignant components are thought to be poor .
Colour Doppler interrogation in some tumours may show marked hypervascularity with arterio-venous (AV) shunting.
Superior to ultrasound especially in assessment of the following areas
•associated hip dislocation
•metastatic assessment in malignant lesions
Signal characteristics can significantly vary depending on the constituent of the teratoma
•T1 - fat components appear high signal, calcific / bony components low signal
•T2 - fluid (cystic) components appear high signal, calcific bony components low signal
•T2* GRE - magnetic susceptibility artifact because of calcifications
•T1 C+ (Gd) - enhancing solid components
Avni FE, Guibaud L, Robert Y et-al. MR imaging of fetal sacrococcygeal teratoma: diagnosis and assessment. AJR Am J Roentgenol. 2002;178 (1): 179-83. AJR Am J Roentgenol (full text) - Pubmed citation Danzer E, Hubbard AM, Hedrick HL et-al. Diagnosis and characterization of fetal sacrococcygeal teratoma with prenatal MRI. AJR Am J Roentgenol. 2006;187 (4): W350-6. doi:10.2214/AJR.05.0152