Renal spindle cell tumours

Differential diagnosis

 

Fibroepithelial polyp of the renal pelvis

young adult with gross painless haematuria, polypoidal filling defect in renal pelvis on IVP, thick fibrous stalk covered by normal urothelium

stromal cells: CD34-, HMB45-, CD117-

 

Fibroma

nodule < 6mm in renal pelvis, often entrapping medullary tubules

stromal cells: cytokeratin-, muscle markers-, CD34-, HMB45-, CD117-

Angiomyolipoma

muscle and adipose tissue components

HMB45+, SMA+

Solitary fibrous tumour

"patternless pattern", dense collagen bands

CD34+, bcl-2+

Haemangiopericytoma

"patternless pattern", dense collagen bands

HHF-35+

Sarcomatoid renal cell carcinoma

plump spindle cells

cytokeratin+

Fibrosarcoma

rare, monomorphic with minimal pleomorphism but a high mitotic count

 

Leiomyoma/leiomyosarcoma

conspicuous pink cytoplasm

desmin+, cytokeratin-

Gastrointestinal stromal tumour

rare

CD117+, CD34+

Embryonal sarcoma / synovial sarcoma

multicystic, cysts lined by hobnail cells

vimentin+, cytokeratin focal +, EMA focal +, CD99+, CD56+, neurofilament+, S100-, CD34-, SMA-, desmin-

Cellular mesoblastic nephroma

infants, densely packed spindle/round blue cells, high mitotic rate, may entrap cystic epithelium with hobnail cells

desmin+

Endometrial stromal sarcoma

 

CD10+, ER+, PR+, desmin variable, SMA variable, HHF-35 variable, cytokeratin-, renal cell carcinoma marker-

Inflammatory myofibroblastic tumour

variable collagen, lymphoplasmacytic infiltrate

vimentin+, SMA+, HHF-35 variable, cytokeratin variable, CD68 variable

Malignant peripheral nerve sheath tumour

wavy fascicles, palisading, thick-walled vessels

S100 focal +

     

References

1Wang, J., L. M. Weiss, et al. (2004). "Usefulness of immunohistochemistry in delineating renal spindle cell tumours. A retrospective study of 31 cases." Histopathology 44(5): 462-71.

This page last revised 14.5.2004.

©SMUHT/PW Bishop