49 year old male with history of hyperlipidemia, hypertension, CKD Stage III and DM presents to the ED with nausea and vomiting along with diffuse constant mild abdominal pain. CT Abdomen Pelvis revealed a left 7.3 cm renal mass, numerous scattered pulmonary nodules and a lesion in the right hepatic lobe (segment 5 and 6). Fine needle aspiration biopsy of the liver revealed metastatic renal cell carcinoma
Definition
- Malignant neoplasm of the kidney made up of epithelial cells with clear or granular cytoplasm arising from proximal convoluted tubule
- First described by Daniel Sennert in 1613
- Introduced by Foot and Humphreys, and Foote et al because of the renal tubular origin of these tumors
Essential features
- Sixth and seventh decades
- Risk factors include smoking, obesity and hypertension. Less commonly, inherited (tuberous sclerosis, Birt-Hogg-Dube and VHL syndromes) and sickle cell disease
Terminology
- Conventional renal cell carcinoma
- Thought to have ascend from adrenal rest and were called ‘hypernephromas’
- Nephrocellular carcinoma
- Grawitz tumor
Epidemiology
- Male predominance
- Caucasian>Asian>African American
- North America, Europe and Australia/New Zealand
- Approximately 90% of the renal epithelial carcinoma
- About 70% of all renal cortical malignancies
Sites
- Renal cortex
- Upper pole of the kidney
- Known to metastasize to weird sites like parotid, anus and thyroid
- Metastasize via hematogenous route
Clinical features
- Triad of hematuria (most common), abdominal pain and a flank mass
Radiology description
- Average size: 7 cm
-
- Heterogenous appearance due to necrosis, hemorrhage and cystic degenerations
- Associated with hypervascular retroperitoneal lymphadenopathy
Prognosis and treatment
- Prognosis depends on histologic grade, sarcomatoid or rhabdoid differentiation, metastasis and tumor necrosis (>10%)
- Poor prognosis if there is loss in chromosome 14q, 4p and 9p
- 5 years survival is 60-80% in Stage I and 5% in Stage IV
- Arterial embolization
- Partial or Radical nephrectomy
- Interleukin 2, sunitinib (Anti-VEGF TKI) therapy, mTOR inhibitor (targeted) therapy
Cytology description
- Clusters of cohesive cells with large round slightly eccentrical placed nucleus and abundant wispy cytoplasm with ill defined edges
Positive stains
- CD10
- RCC
- CA-IX
- PAX 8
- PAX 2
- EMA
Negative stains
- CK 7
- CK20
- Hale’s colloidal iron
- Inhibin
- CD68
Molecular/cytogenetics description
- Somatic mutations or deletions of hypermethylation of chromosome 3p
- Non random chromosomal changes on chromosomes 3p and 14q
- Gain of chromosome 5q22-qter and trisomy 7
Differential diagnosis
- Histocytes
- Benign tubular cells
- Angiomyolipoma
- Adrenal cortical cells