Editing Pediatrics: Renal and Adrenal Oncology (section)

=== Congenital Mesoblastic Nephroma ===

==== Epidemiology ====
*'''<span style="color:#ff0000">Most common renal tumor in infants'''
** Most common renal tumor diagnosed on pre-natal US
** Most common tumor in infants > 4 months of age
* '''Mean age at diagnosis of 3.5 months (in contrast, the median age for diagnosis of a Wilms' tumor is 3.5 years)'''

==== Subtypes (2) ====
# '''Classic type'''
#* Far more common
#* '''Rarely recur,''' provided surgical margins are negative
# '''Cellular variant'''
#* Consists of atypical spindle cells with frequent mitotic figures (25-30/10 hpf) and necrosis
#* Considered a variant of a '''fibrosarcoma'''
#* Associated with both '''local recurrence and widespread metastasis.'''

==== Diagnosis and Evaluation ====
*'''Imaging'''
**'''Typically infiltrative (whereas Wilms' tumors displace and compress renal architecture)'''

==== Management ====
* '''<span style="color:#ff0000">Radical nephrectomy'''
** '''Biopsy and partial nephrectomy are not recommended''' since the tumour occasionally extends into the hilum or perirenal soft tissue; complete excision is important to prevent local recurrence.

==== Follow-up ====
* Surveillance by interval 6 month abdominal US for the first 2 years is usually recommended for the classic variant and more aggressive follow-up with interval CT or MRI scans of the lungs and abdomen are recommended at 3-6 intervals for the first two years for the cellular variant