This document discusses tumours of the kidney. It begins by defining benign and malignant tumours in general. It then describes several types of benign kidney tumours, including cortical adenomas, oncocytomas, angiomyolipomas, and metanephric adenomas. Malignant kidney tumours are also briefly mentioned. The document focuses on Wilms' tumour, providing details on its epidemiology, etiology, pathogenesis, clinical presentation, morphological features, diagnosis and treatment. Wilms' tumour is described as the most common malignant kidney tumour in children.

1. TUMOURS OF THE KIDNEY
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2. TUMOUR
• Definition :
• An abnormal benign or malignant new growth
of tissue that possesses no physiological
function and arises from uncontrolled usually
rapid cellular proliferation.
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3. TYPES
• 1. BENIGN RENAL TUMOUR
• 2. MALIGNANT RENAL TUMOUR
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4. BENIGN TUMOUR
• DEFINITION :
• A benign tumor is a mass of cells (tumor) that
lacks the ability to invade neighboring tissue
or metastasize. These do not spread into, or
invade, nearby tissues however they can
sometimes be quite large.
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5. BENIGN RENAL TUMOURS
• A benign tumor is not a malignant tumor, which is
cancer.
• It does not invade nearby tissue or spread to other
parts of the body the way cancer can.
• In most cases, the outlook with benign tumors is
very good.
• But benign tumors can be serious if they press on
vital structures such as blood vessels or nerves.
• As there is universal increase in the use of
radiological imaging, benign renal masses are being
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6. MALIGNANT TUMOUR
• DEFINITION:
• A tumor that invades surrounding tissues, is
usually capable of producing metastases, may
recur after attempted removal, and is likely to
cause death unless adequately treated.
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7. INTRODUCTION
• Both benign and malignant tumours occur in the
kidney, the latter being more common.
• These may arise from………….
• Renal tubules
• 1.Adenoma,
2. Adenocarcinoma
• From Embryonic tissue……
• 1.Mesoblastic nephroma
• 2.Wilm’s Tumour(Nephroblastoma)
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8. • From mesenchymal tissue……
• 1.Angiomyolipoma
• 2.Medullary interstitial tumour
• From Epithelium of Renal pelvis……
• 1.Urothelial carcinoma
• Besides these tumours, the kidney may be the
site of the secondary tumours
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9. CLASSIFICATION OF THE KIDNEY
TUMOURS
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10. BENIGN KIDNEY TUMOURS
• Benign tumours are usually small and are
often an incidental finding at autopsy or
nephrectomy
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11. 1. Cortical Adenoma
• Cortical tubular adenomas are common than
other benign renal neoplasm's.
• They are frequently multiple and associated
with chronic Pyelonephritis or benign
nephrosclerosis.
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12. • Asymptomatic .
• Despite the classification of adenoma as a
benign tumor, difficult to differentiate from
renal carcinoma.
• Unknown etiology .
• Small and slow growing .
• Look very much like malignant RCCs.
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13. • Gross :
• These tumours may form tiny nodules up to 3
CM in diameter.
• They are encapsulated and white or yellow.
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15. • Microscopic :
• They are composed of tubular cords or papillary
structures projecting into cystic space.
• The cells of adenoma usually uniform, cuboidal
with no atypicality or mitosis.
• Size of the tumour rather than histologic criteria
is considered more significant parameter….
• Tumour larger than 3 cm diameter are potentially
malignant and metastasising.
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16. MICROSCOPIC H & E
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17. • Oncocytoma is a benign epithelial tumour arising
from the collecting ducts.
• Benign, unifocal renal tumor that averages 5 to 8 cm
in diameter but can reach larger sizes;
• however, the presence of malignant elements has
been known to occur.
• More often in men than women .
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18. • Unknown etiology .
• Found incidentally .
• Partial or radical nephrectomy is the safest
method of treatment because of unreliability
of differentiating it from RCC preoperatively
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19. • Grossly :
• The tumour is encapsulated and has variable
size.
• C/s …. Is Homogeneous and has characteristic
mahpgany-brown or tan colour.
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21. • Microscopic :
• The tumour cells are plump with…….
• Abundant
• Finely granular
• Acidophilic cytoplasm and
• Round Nuclei
• Electron microscopy demonstrates numerous
mitochondria in the cytoplasm.
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23. • Unusual tumors of the kidney .
• Often but not always associated with
TUBEROUS,SCLEROSIS .
• Histologically, they are composed of fat cells,
blood vessels, and sheets of smooth muscle
cells.
• Profuse internal hemorrhage can occur
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25. • Malignant elements are present in about one
quarter of them and may lead to metastasis .
• Asymptomatic lesions smaller than 4 cm
should be followed with yearly ultrasounds.
• Larger tumors should be considered for
embolization or renal-sparing surgery.
• Conservative surgical therapy is necessary
because of frequent bilaterality and
multiplicity.
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26. GROSS & MICROSCOPC
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27. • Rare .
• Small .
• Typically found in smooth muscle –containing
areas of the kidney including renal capsule
and renal pelvis .
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30. • Seen in middle aged females .
• Best detected radio-logically by CT scan . ( due
to high fat content .)
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32. • Very small in size ( average 0.5 cm ) or less
• Asymptomatic .
• More commonly found in women than men.
• Usually occur on the rim of the kidney
• May reach large size before being detected
• Because they can’t be distinguished from
malignant growths, they are often removed
through partial or complete nephrectomy .
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36. • PEADIATRIC RENAL TUMORS
• Wilm’s tumor ( nephroblastoma ) .
• RENAL TUMORS IN ADULTS
• Hypernephroma adenocarcinoma(RCC)
• Transitional cell tumor (TCC) of renal pelvis
• Squamous cell carcinoma
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38. • WILM’S TUMOUR
• RHABDOMYOMA
• CLEAR CELL CARCINOMA
• MESOBLASTIC NEPHROMA
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40. CONTENTS…………
• Introduction
• Epidemiology
• Etiology
• Pathogenesis
• Clinical presentation
• Morphological features
• Diagnosis
• Treatment
• Prognosis…….
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41. • INTRODUCTION
• Wilms tumor (also called Wilms' tumor or
nephroblastoma) is a type of cancer that starts in
the kidneys.
• It is the most common type of kidney cancer in
children.
• It is named after Max Wilms, a German doctor
who wrote one of the first medical articles about
the disease in 1899.
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42. • Nephroblastoma or Wilm’s tumour is an
embryonic tumour derived from primitive
renal epithelial and mesenchymal
components.
• It is the most common abdominal malignant
tumour of young children b/w 1- 6 yr of age
with equal sex incidence.
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43. Epidemiology
• Second most common pediatric abdominal tumor and
• most common renal malignancy
• Incidence of Wilms’ tumor is 8 cases per million
• children under age 15(1-6 yrs)
• About 500 new cases per year
• Accounts for 6% of all childhood malignant tumors
• Presents between age 1-5; most commonly age 5
• 66% before age 5
• 95% before age 10
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44. ETIOLOGY & PATHOGENESIS
• Wilm’s tumor is thought to be caused by
alterations of genes responsible for normal
genitourinary development.
• Examples of common congenital anomalies
associated with Wilms tumor are , double
collecting system, horseshoe kidney, and
hypospadias.
• Environmental exposures, although considered,
seem relatively unlikely to play a role.
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45. • Wilm’s tumour has following etiologic associations
…………
• 1. A defect in chromosome 11 p 13 results in abnormal
growth of metanephric blastema without
differentiation into normal tubules and glomeruli.
• 2. A higher incidence has been seen in monozygotic
twins & cases with family history.
• 3.Asociation of wilm’s tumour with some other
congenital anomalies has been observed, especially of
the genitourinary tract.
• 4.A few other malignancies are known to have higher
incidence of wilm’s tumour. These include …..
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46. • - osteosarcoma
• - Botyroid sarcoma
• - Retinoblastoma
• - neuroblastoma etc…..
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52. Nephrogenic rest
• Nephrogenic rest: A fragment of embryonic tissue in
the kidney retained after the period of embryonic
development.
• Nephrogenic rests are precursors (forerunners) of
Wilms tumor.
• Two distinct categories of nephrogenic rest are
recognized on the basis of their topographical
relation to the renal lobe.
•
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53. • Intralobar nephrogenic rests occur within the
renal lobe and develop as the result of events
early in renal development.
• Pelilobar nephrogenic rests are confined to
the periphery of the renal lobe and are related
to late kidney development.
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54. Presentation
• No tumor-specific symptoms
• 1/3rd patients may have anorexia, vomiting, malaise
• Most common presentation is painless abdominal mass
• Physical Exam
• Smooth, palpable large abdominal mass
• May reveal HTN
• Hematuria
• Associated congenital abnormalities
• Check labs – associated with Von Willebrand’s Disease
in up to 10% of cases
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56. Morphological Features
• Gross :
• The tumour is usually quite large, spheroidal, replacing
most of the kidney.
• It is generally solitary and unilateral but 5-10% cases
may have bilateral tumour.
• On C/s – the tumour shows characteristic variegated
appearance ,Soft fishsflesh-like grey-white to creamy –
yellow tumour with foci of necrosis and haemorrhages
and grossly identifiable myxomatous or cartilaginous
elements.
• Invasion into renal vein is grossly evident in half the
cases
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60. • Microscopic Ex:
• Nephroblastoma shows mixture of primitive
epithelial and mesenchymal elements.
• Most of the tumour consist of small, round to
spindled, anaplastic, sarcomatoid tumour
cells.
• Mesenchymal elements such as smooth and
skeletal muscle, cartilage and bone, fat cells
and fibrous tissue, may be seen.
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62. Diagnostic Considerations
• Conditions to be considered in the differential diagnosis of Wilms tumor
include the following:
• Mesoblastic nephroma - Most common renal tumor in the first month of
life
• Renal cell carcinoma
• Clear cell sarcoma of the kidney
• Rhabdoid tumor of the kidney
• Nonmalignant mass
• Hydronephrosis
• Multicystic kidney disease
• Renal cyst
• Renal thrombosis
• Dysplastic kidney
• Renal hemorrhage
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63. Laboratory Investigations…….
• Complete blood count (CBC)
• Chemistry profile - Including kidney function
tests and routine measurements of
electrolytes and calcium
• Urinalysis
• Coagulation studies
• Cytogenetics studies, including 1p and 16q
deletion
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64. Imaging Studies
• Four-field chest radiography
• Renal ultrasonography
• CT scanning
• MRI scanning
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65. Rx……….
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67. Prognosis
• Approximately 80-90% of children with a
diagnosis of Wilms tumor survive with current
multimodality therapy.
• Patients who have tumors with favorable
histology have an overall survival rate of at
least 80% at 4 years after the initial diagnosis,
even in patients with stage IV disease.
• The 4-year relapse-free and overall survival
rates in patients with favorable-histology
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