Pediatrics: Genitourinary, Solid Organ Flashcards
Solid renal mass in a 0-3 y/o…
- Nephroblastomatosis
- Mesoblastic nephroma
Solid renal mass in a 4 y/o…
- Wilms (very rare after age 10)
- Wilms variants
- Lymphoma
- Multilocular cystic nephroma (if cystic, not solid)
Solid renal mass in a teenager…
- Renal cell carcinoma
- Lymphoma
Solid renal mass identified on day 1 of life…
Think mesoblastic nephroma
Note: AKA
“solid tumor of infancy”.
Management of nephroblastomatosis
Screening ultrasounds every 3 months until age 7-8 (due to risk of developing Wilms tumors)
Nephroblastomatosis
Persistent nephrogenic rests beyond 36 weeks gestation that present as solid renal masses
Bilateral Wilms tumors…
Nephroblastomatosis (persistence of fetal nephrogenic rests)
Can you be born with a Wilms tumor?
No, if born with a renal tumor think mesoblastic nephroma
What is the classic site of metastases for Wilms tumor?
Lungs
What is the classic site of metastases for a clear cell Wilms tumor?
Bone
What is the classic site of metastases for a rhabdoid Wilms tumor?
Brain
Next step: can’t differentiate between a multi-cystic nephroma and a cystic Wilms tumor
Surgical resection
Note: Never biopsy a possible Wilms tumor (you can seed tumor).
Adolescent renal cell carcinoma is associated with…
- Prior chemotherapy (translocation subtype)
- Sickle cell trait (medullary subtype)
- Von Hippel-Lindau (clear cell subtype)
3 y/o with ultrasound demonstrating nephroblastomatosis and some necrotic regions…
Think Wilms tumor
Note: Uncomplicated nephroblastomatosis should not have any necrosis.
Imaging appearance of nephroblastomatosis
Focal homogenous renal mass
OR
Hypodense rind surrounding the kidney
Note: NO necrosis; any necrosis -> think Wilms.
Mesoblastic nephroma
A generally-benign fetal hamartoma of the kidney
Note: This is the most common neonatal renal tumor (80% diagnosed in the first month of life).
9 month old with a renal tumor that looks like Wilms…
Think mesoblastic nephroma (Wilms tumors are extremely rare before 1 year old)
Prenatal ultrasound demonstrates the left kidney to have numerous tiny cysts with a normal right kidney…
Think multi cystic dysplastic kidney (no actual functioning renal tissue)
Multicystic dysplastic kidney is associated with…
Abnormalities in the contralateral kidney (50%)
Note: Most commonly this is a UPJ obstruction.
How can you differentiate between multi cystic dysplastic kidney and bad hydronephrosis?
- In hydronephrosis, the cystic spaces communicate with the renal pelvis
- Renal scintigraphy can be used in difficult cases (multi cystic dysplastic kidneys have no excretory function)
Wilms tumors are associated with…
- Beckwith-Wiedemann
- Sotos
- WAGR
- Drash
Beckwith-Wiedemann
- Macroglossia
- Wilms
- Omphalocele
- Hepatoblastoma
Sotos
- Macrocephaly
- Mental retardation
- Ugly face
WAGR
- Wilms
- Aniridia
- Genital anomalies
- Growth Retardation
Drash
- Wilms
- Pseudohermaphroditism
- Progressive glomerulonephritis
Wilms in a 1 y/o…
Look for other associated syndromes/anomalies:
- Hemihypertrophy
- Hypospadias
- Cryptorchidism
Wilms tumors are NEVER present prior to what age?
2 months (and extremely rare prior to 1 year)
What are the common Wilms variants?
- Clear cell (likes to cause lytic bone mets)
- Rhabdoid (likes to cause aggressive rhabdoid brain tumors, horrible prognosis)
What percentage of pts with a Wilms tumor will have bilateral Wilms tumors?
5-10%
4 y/o with a cystic renal mass that protrudes into the renal pelvis…
Multilocular cystic nephroma
Multilocular cystic nephromas are most common in what age groups?
- Young boys (~4 y/o)
- Middle aged women (~40s)
Note: Some people separate these into two different diseases: pediatric cystic nephromas and adult cystic nephromas.
What is the most common renal malignancy of childhood?
Wilms tumor (followed by renal cell carcinoma)
What is the most common subtype of renal cell carcinoma in children?
translocation carcinoma
Note: Clear cell carcinoma, which is the most common subtype in adults, is rare in kids.
Kids with clear cell renal cell carcinoma should be screened for…
Von Hippel-Lindau
Kids with translocation renal cell carcinoma often have a history of prior…
Cytotoxic chemotherapy
Classic imaging appearance of translocation renal cell carcinoma
Solid, enhancing renal mass that is denser than renal cortex on non contrast CT and demonstrates expansile growth
Multiple, bilateral, round, expansile renal masses in a 4 y/o…
Think lymphoma
Lymphoma involving the kidneys in children is most often primary/secondary
Always secondary (hematogenous spread or direct invasion of lymphoma)
Note: Primary renal lymphoma is virtually nonexistent.
Best initial imaging test for suspected bladder cancer in a kid
Bladder ultrasound (with a full bladder)
What is the most common malignant bladder tumor in children?
Rhabdomyosarcoma
Kid with bladder obstruction and bladder ultrasound demonstrates a large, nodular bladder mass…
Think rhabdomyosarcoma
Note: Specifically, the botryoid subtype has a nodular, bunch-of-grapes appearance.
Most common location for pediatric rhabdomyosarcoma
Head/neck (specifically the orbit and nasopharynx)
Which rhabdomyosarcoma subtype looks like a bunch-of-grapes?
Botryoid rhabdomyosarcoma
What is the most common age rage for rhabdomyosarcoma
Bimodal: 2-4 and 15-17
What percentage of rhabdomyosarcoma cases have metastatic disease at the time of presentation/diagnosis?
20%
What is the most common atraumatic extra-testicular scrotal mass in a young male?
Paratesticular rhabdomyosarcoma
Note: If there was trauma, think hematoma.
