Renal tumors

1. PREPARED BY DR. Zain Alabdeen Garwash
Supervised by
Dr Tawfiq Alkabab

3. Renal tumors
 Most renal tumors arise from the renal parenchyma
( referred to as renal cell tumors, renal cortical
tumors, or renal parenchymal tumors ),
 A much smaller number arising from the urothelium
of the renal collecting system (urothelial carcinoma
or transitional cell carcinoma ) or the mesenchyma
(as angiomyolipoma, lieomyoma, liposarcoma )
 Benign renal parenchymal tumors include renal
oncocytoma(5%) and the rare metanephric adenoma
, metanephric adenofibroma, and papillary renal cell
adenoma.

4. Renal tumors
 Malignant renal cell tumors occur nearly twice as
often in men as in women
 The age at diagnostic is generally older than
40years,
 Bilateral multifocal renal tumors are present in
approximately 5% of patient with sporadic renal
tumors

5. Renal Tumors Classification
 BENIGN NEOPLASMS
 EPITHELIAL TUMORS
OF PARENCHYMA
 Renal papillary
adenoma
 Oncocytoma
 Metanephric adenoma
 MALIGNANTN EOPLASMS
 EPITHELIAL TUMORS OF
PARENCHYMA
 Adenocarcinoma
 Renal cell carcinoma
 Clear cell carcinoma
 Papillary carcinoma
 Chromophobe renal carcinoma
 Xp11 translocation carcinoma
 Collecting duct ( bellini duct )
carcinoma

6. Renal Tumors Classification
 BENIGN NEOPLASMS
 EPITHELIAL TUMORS
OF RENAL PELVIS
Transitional cell
papilloma
 MALIGNANT NEOPLASMS
 EPITHELIAL TUMORS OF
RENAL PELVIS
Transitional cell carcinoma
 Squamous cell carcinoma
 Adenocarcinoma of the
renal pelvis
Undifferentiated carcinoma
of renal pelvis

7. Renal Tumors Classification
 BENIGN NEOPLASMS
 EMBERYONAL TUMORS
Mesoblastic nephroma
Multicystic nephroma
 MALIGNANT NEOPLASMS
 EMBERYONAL TUMORS
Wilms tumors
(Nephroplastoma)

8. Renal Tumors Classification
 BENIGN NEOPLASMS
 NON EPITHELIAL TUMORS
 Angiomyolipoma
 Leiomyoma
 Medullary interstitial
tumor ( fibroma )
 Miscellaneous
 Juxtaglumerular cell
tumor
 MALIGNANT NEOPLASMS
 NON EPITHELIAL TUMORS
 Sarcoma

9. Renal masses classification by pathologic features

11. Renal papillary adenoma
 papillary adenoma are most commone renal epithelial
neoplasm.
 Epithelial lesions with a tubulo-papillary architecture
 Findings and occur in up to 23% of autopsy patients.
 Usually measuring less than 5mm.
 They are usually subcapsular and solitary.
 Resemble low grade RCC but considered benign because of
small size.
 No reliable histopathologic, ultrastructural, or
immunohistochemical criteria to distinguish benign from
malignant lesions of the kidney

12. Renal papillary adenoma
Incidence of papillary adenomas in :
 Increases with age
 Male sex
 Acquired renal cystic disease
Now generally belieived that ,All solid renal epithelium-
derived masses are potentially malignant.

13. Renal papillary adenoma(cont):
 Histologically, cells are uniform with benign nuclei
and arearranged as either tubular, papillary, or
tubulopapillary, similar to papillary RCC
 The diagnosis of papillary adenoma as a benign
entity remains controversial
 Papillary adenomas are 5 mm or smaller and are
therefore not readily diagnosed on imaging
 The changing paradigm of active surveillance for
small renal masses certainly supports observation
of these small lesions when papillary adenoma is
considered

14. Metanephric adenoma
 Rare benign epithelial lesion in the kidney
 Representing approximately 0.2% of renal masses
 It can present at any age, although peaks in the fifth decade
 2 : 1 female:male ratio
 Metanephric adenoma may exist on a continuum with Wilms
tumors and papillary RCC and can be distinguished based on
histology and immunohistochemical staining.
Presentation :
 Symptoms such as flank pain, gross hematuria, a palpable
mass, and associated with polycythemia.
 The cause of polycythemia in metanephric adenoma has been
investigated using in vitro cell cultures, which demonstrated the
production of erythropoietin, IL-6, IL-8.

15. Metanephric adenoma
Grossly:
 Well-circumscribed, tan/brown masses.
 Have been reported up to 15 cm.
Histologically :
 Uniform cells with bland nuclei and scant cytoplasm
 Acinar, follicular, tubulopapillary,and glomerular
structures.
 Although histology may differentiate Wilms tumor
from metanephric adenoma.
 Importantly, necrosis,atypia, or mitotic figures,
features commonly found in Wilms tumors, are not
present

16. Metanephric adenoma (cont):
Diagnosis :
CT scan
 These masses appear
hypovascular with minimal
enhancement and
calcifications .
 Isodense on non-contrast
phase
 Unfortunately, radiographic
findings may be insufficient
to establish the diagnosis.and
as such,these are often
diagnosed after surgical
resection.

17. Metanephric adenoma (cont):
Biopsy
 Fine-needle aspiration or core biopsy
Immunohistochemical studies:
 Positive for Wilms tumor protein WT1 and
CD57.
 Negative for α-methylacyl CoA racemase
(AMACR)

18. Renal Oncocytoma
 3-5% of all renal tumors
 They occur simultaneously with RCC in 7–32%
of cases.
 Oncocytomas are derived from the distal renal
tubules similar to chromophobe RCC,

19. ONCOCYTOMA
Grossly
 Spherical,capsulated
 Brown/tan colour
 Homogeneous
 well circumscribed
 A central scar is
commonly
 Necrosis or
hypervascularity is
rarly

20. ONCOCYTOMA
Presentation
 Age 40-60yrs
 Oncocytomas often (83%) present as an
incidental finding .
 Loin pain or haematuria.
 The diagnosis of oncocytoma is predominantly
pathologic because there are no reliable
distinguishing clinical characteristics.
 No characteristic features of the tumors appear on
CT, ultrasound (US), intravenous urography (IVU),
or MRI.

21. ONCOCYTOMA
Dignosis:
 Definitive diagnosis of oncocytoma is typically
postoperative.
 As most renal oncocytomas are diagnosed after
surgical resection (because of perceived risk of
RCC)

22. CT Angiography imaging
1. Well-defined
2. Central stellate
scar
3. Spoke wheel
appearance of
tumor arterioles
4. The “lucent rim
sign of the
capsule.

23. MRI
 TI-weighted images
reveals a low signal-
intensity mass , which
differs from the
intermediate to high signal
intensity often seen in renal
cell carcinomas.
 T2-weighted images,
oncocytomas show a high
signal intensity.
 Oncocytoma. Coronal T1-weighted MR I
acquired following the injection of
intravenous contrast media shows an
enhancing mass in the inferior pole of the
right kidney (arrow).
 The low-signal central scar (arrowhead) is
typical of oncocytoma

24. ONCOCYTOMA
Biopsy
 Fine-needle aspiration or core biopsy
 High rates of false-negative
Immunohistochemical studies
 Hales colloidal iron (HCI) stain -ve ( chromophobe
and RCC +ve)
 Cytokeratin 18 -ve
 Vimentin antibodies -ve

25. ONCOCYTOMA
Treatment
Treatment options for a known oncocytoma range from
 Observation (active surviellance)
Thermal ablation
Laparoscopic or OPN
RN

26. Angiomyolipoma

27. Angiomyolipoma (Renal Hamartoma)
 AML accounts for less
than 10% of renal
tumors
 AML is derived from
perivascular epithelioid
cells
benign mesenchymal
tumor composed
 Mature adipose tissue
 Smooth muscle
 Thick-walled vessels

28. Types
• Tuberous sclerosis (20%)
50% of patients with TSC develop AML
 Tuberous sclerosis is a familial inherited disorder
comprising adenoma sebaceum, mental retardation,
and epilepsy.
 F: M = 2:1 ,
Multiple, bilateral, larger
Growth rate 20% per year
Likely to cause spontaneous hemorrhage..25%

29. Epilepsy & M.R
& Retinal
phakomas
Acanthoma
sebacum
Hamartoma
(renal, hepatic,
splenic)

30. Types (CONT)
• Sporadically (80%)
 4: 1 more likely in women, middle age
 Slow growth rate 5% per year
 Unilateral, unifocal, small
Extra renal
 Retroperitoneal lymph nodes, liver, and spleen have
been noted to have AMLs identical to the primary
renal tumor.
 However, these have been considered to represent
multifocality rather than metastases

31. Presentation
 Incidental (50%), loin pain , mass ,
hematuria
 Massive retroperitoneal bleeding (10%):
Wunderlich’s syndrome

32. Angiomyolipoma (Cont)
Diagnosis:
 USG:
Bright echo- pattern
without acoustic shadow
(vs stone)

33. Angiomyolipoma (Cont)
 CT imaging:
 presence of adipose tissue (low HU −20 to −80)
 AML do not calcify, the presence of calcification should suggest
renal carcinoma, even when fat is identified.
 Renal angiogram shows increased vascularity & aneurysmal
dilation characteristic of AML
Mass fat-containing
1- AML
2-liposarcoma
3- RCC

34. Angiomyolipoma (Cont)
 MRI :
Appear hyperintense on T1 and T2

35. Angiomyolipoma (Cont)
 Immunohistochemical
studies:
 Positive immunoreactivity
for HMB-45
 The major risk factors for
bleeding :
Tumor size (>4cm)
The grade of angiogenic
component of the tumor.
Presence of tuberous
sclerosis .
 Complications:
Retroperitoneal
bleeding
Bleeding into the
urinary collection
system

36. Angiomyolipoma (Cont)
 Treatment :
Surgery: Most cases NSS, some RN if large Tumor.
Others: selective arterial embolisation (SAE) and
radiofrequency ablation (RFA).
 SAE in AML management for three major
reasons:
The tumor is benign.
Symptoms result most often from hemorrhage.
Embolization can preserve healthy renal parenchyma.

37. Angiomyolipoma (Cont)
 More recent data also suggests that
immunosuppressive agents such as sirolimus (an
inhibitor of mammalian target of rapamycin)
may also be effective in treating AML arising in
patients with TS

38. LEIOMYOMA

39. Leiomyoma
 Arise from smooth muscle cells from capsule, peripelvic
tissue
 Small solid renal are <2 cm
 Most were asymptomatic
 more often in women(2 : 1 predominance)
gross examination:
 These tumors appear well circumscribed and firm.
 Tumors can range in size and may have associated
calcifications and focal cystic degeneration.

40. Leiomyoma (cont) :
Diagnosis:
CT Imaging :
 Tumors are hyperdense
relative to the renal
parenchyma on noncontrast
imaging, with clear sharp
margins.
 With contrast administration,
homogeneous enhancement
is observed, which increases
in later phases, except in the
setting of large masses, in
which hemorrhage or cystic
changes may result in
heterogeneous patterns.

41. Treatment :
Nephronsparing (NSS) approaches preferred
when treatment is considered.

42. Hemangiomas

43. Hemangiomas
 Benign vascular tumors that affect young adults <
age of 40 yrs.
 Typically single and unilateral .
 Most part occur close to the renal pyramids and
pelvis.
 Renal hemangiomas are commonly sporadic.
 But can occur with syndromes Klippel-Trenaunay
Sturge-Weber and systemic angiomatosis.
 present with profuse or relapsing gross, painless
hematuria

44. Hemangiomas (Cont):
Diagnosis :
 RGP segmental” sign of
pyeloparenchymal extravasation
from the fornix
 CT angiography.
 MR angiography hypointense areas
on T1W images, hyperintense areas
on T2W images.
 Direct visualization by flexible
ureterorenoscopy is the method of
choice.

45. Hemangiomas (Cont):
Treatment:
 When available, the electrocautery or laser
constitutes also the treatment of choice, if
the lesion is accessible.
 In the absence of such facilities, open
surgery is indicated in cases of persistent
bleeding.

46. Juxtaglomerular cell tumor (reninoma)

47. Juxtaglomerular cell tumor
(reninoma)
 Rare benign renin-secreting tumor that arises from the
juxtaglomerular cell apparatus.
 Women in the third and fourth decades are most commonly
affected.
 Small (<3 cm).
 Clinical presentation is dominated by hypersecretion of renin
and includes:
 Hypertension
 Hypokalemia
 Headaches
 Hyperaldosteronism
 High renin
 Associated symptoms such as polydipsia, polyuria, myalgia.

48.  Diagnosis is confirmed by selected renal vein
sampling for renin
 Treatment Surgery Nephroctomy ,PN

49. Thank you