Renal Cell Carcinoma¶
Chapter 90 | Part 4: Oncology and Hematology
KEY CLINICAL POINTS¶
- Renal cell carcinoma (RCC) accounts for 90–95% of kidney malignancies, with clear cell carcinoma being the most common subtype (70% of cases).
- RCC incidence has risen to ~81,000 annual cases in the U.S., with a male-to-female ratio of 2:1 and peak incidence between 55–75 years.
- Genetic syndromes like von Hippel-Lindau (VHL) and Birt-Hogg-Dubé syndrome are associated with hereditary RCC, with VHL conferring a 70% lifetime risk of clear cell RCC.
- Metastatic RCC is treated with targeted therapies (e.g., VEGF/TKIs, mTOR inhibitors) and immunotherapy (e.g., checkpoint inhibitors like pembrolizumab, nivolumab).
- Staging (AJCC TNM system) guides treatment: 77% 5-year survival for localized disease vs. <10% for distant metastases.
1. DEFINITION & OVERVIEW¶
Renal cell carcinoma (RCC) is the most common malignancy of the kidney, representing 90–95% of kidney cancers. It arises from the renal tubular epithelium and is characterized by resistance to cytotoxic chemotherapy, responsiveness to antiangiogenic agents, and immune infiltration. RCC includes distinct subtypes (clear cell, papillary, chromophobe) with varying genetic and clinical features.
Table 90-1: Hereditary Renal Cell Tumors¶
| SYNDROME | CHROMOSOME (S) | GENE | PROTEIN | KIDNEY TUMOR TYPE | ADDITIONAL CLINICAL FINDINGS |
|---|---|---|---|---|---|
| von Hippel-Lindau syndrome | 3p25 | VHL | von Hippel-Lindau protein | Clear cell | Hemangioblasto ma of the retina and CNS; pheoc hromocytoma; renal cysts |
| Hereditary papillary RCC | 7p31 | MET | MET | Papillary | Bilateral and multifocal kidney tumors |
| Hereditary leiomyomatosis and RCC (HLRCC) | 1q42 | FH | Fumarate hydratase | FH-deficient/HL RCC syndrome– associated RCC | Leiomyoma; uterine leiomyo ma/leiomyosarco ma |
| Birt-Hogg-Dubé syndrome | 17p11 | FLCN | Folliculin | Chromophobe; clear cell; oncocytoma | Facial fibrofolliculoma; pulmonary cysts |
| SYNDROME | CHROMOSOME (S) | GENE | PROTEIN | KIDNEY TUMOR TYPE | ADDITIONAL CLINICAL FINDINGS |
|---|---|---|---|---|---|
| Tuberous sclerosis | 9q34/16p13 | TSC1/TSC2 | Hamartin/Tuberi n | Angiomyolipoma s; RCC with eosinophilic solid and cystic (ESC) appearance | Angiofibroma; ly mphangioleiomy omatosis; renal cysts |
| BAP1 tumor predisposition syndrome | 3p21 | BAP1 | BAP1 | Clear cell; chromophobe; papillary | Atypical Spitz tumors; uveal melanoma |
Table 90-2: Classification of Malignant Epithelial Neoplasms of the Kidney¶
| CARCINOMA TYPE | CHARACTERISTIC GROWTH PATTERN | CHROMOSOMAL EVENTS | GENES WITH RECURRENT SOMATIC ALTERATIONS |
|---|---|---|---|
| Clear cell | Varying growth patterns (acinar, solid, sarcomatoid) | 3p–, 5q+, 14q–, 9p– | VHL, PBRM1, BAP1, SETD2 |
| Papillary | Papillary or sarcomatoid | +7, +17, 9p– | MET, CDKN2A (focal deletions) |
| Chromophobe | Solid, tubular, or sarcomatoid | Whole arm losses (1, 2, 6, 10, 13, 17, 21) | TP53, PTEN, TERT promoter |
| TFE3-rearranged | Mimicking clear cell/papillary variants | Xp11.2 translocations; t(6;11) translocations | TFE3 gene fusions, TFEB gene fusions |
| SMARCB1-deficient renal medullary carcinoma | Varying growth patterns (cribriform, sarcomatoid) | +8q, 22q–, 23q translocations | SMARCB1 (focal deletions, mutations, gene fusions), SETD2 |
1.1 Subtypes and Classification¶
RCC is classified into subtypes based on histology and genetics: clear cell (70%), papillary (10–15%), chromophobe ( ≤ 5%), TFE3-rearranged (<5%), and SMARCB1-deficient medullary carcinoma (rare, aggressive). Molecular alterations (e.g., VHL, PBRM1, MET) define these subtypes.
1.2 Paraneoplastic Syndromes¶
RCC may present with paraneoplastic syndromes including erythrocytosis, hypercalcemia, Stauffer’s syndrome (nonmetastatic hepatic dysfunction), and acquired dysfibrinogenemia. These syndromes are associated with advanced disease or specific subtypes.
2. EPIDEMIOLOGY¶
RCC is the seventh most common cancer in the U.S., with ~81,000 annual cases and ~15,000 deaths. Incidence peaks between 55–75 years, with a male-to-female ratio of 2:1. Risk factors include smoking, obesity, hypertension, and genetic syndromes (e.g., VHL, HLRCC, Birt-Hogg-Dubé).
2.1 Incidence and Demographics¶
Annual incidence rose to ~81,000 cases in the U.S. (2018–2020), with ~15,000 annual deaths. Peak incidence occurs between 55–75 years, and it is uncommon in those <45 years. Male predominance (2:1 ratio).
2.2 Risk Factors¶
Smoking, obesity, hypertension, and chronic renal failure increase risk. Genetic syndromes (VHL, HLRCC, Birt-Hogg-Dubé, tuberous sclerosis) are associated with hereditary RCC. Polycystic kidney disease with renal failure also elevates risk.
3. ETIOLOGY & PATHOPHYSIOLOGY¶
RCC arises from renal tubular epithelium with distinct genetic and molecular mechanisms. Key drivers include VHL inactivation (leading to VEGF overexpression), MET mutations, and chromosomal abnormalities (e.g., 3p loss, 9p deletion).
3.1 Genetic Alterations¶
Clear cell RCC: VHL, PBRM1, BAP1, SETD2 mutations. Papillary RCC: MET amplification, CDKN2A deletions. Chromophobe RCC: TP53, PTEN, TERT promoter mutations. TFE3-rearranged: Xp11.2 translocations. SMARCB1-deficient: SMARCB1 mutations.
3.2 Molecular Pathways¶
VHL inactivation leads to HIF stabilization and VEGF overexpression, promoting angiogenesis. MET activation drives papillary RCC. TFE3/TFEB fusions in TFE3-rearranged tumors alter transcriptional programs.
4. CLINICAL FEATURES¶
RCC often presents with asymptomatic incidental findings on imaging. Common symptoms include hematuria, flank pain, palpable mass, weight loss, and anemia. Paraneoplastic syndromes (e.g., erythrocytosis, hypercalcemia) may occur.
4.1 Presentation¶
Hematuria (30–50%), flank/abdominal pain, palpable mass, weight loss, anemia, and varicocele. Incidental detection on imaging is common. Paraneoplastic syndromes (e.g., Stauffer’s syndrome, erythrocytosis) may occur.
4.2 Complications¶
Metastases to lungs, liver, bones, brain. Renal vein/IVC invasion, lymph node involvement, and distant spread (e.g., liver, bone).
5. DIFFERENTIAL DIAGNOSIS¶
Differential diagnoses include transitional cell carcinoma (renal pelvis), renal sarcomas, lymphomas, Wilms’ tumor, and metastases from other cancers. Imaging and histopathology are critical for distinction.
5.1 Mimicking Lesions¶
Transitional cell carcinoma (renal pelvis), renal sarcomas, lymphomas, Wilms’ tumor, and metastases from other organs. Imaging (CT/MRI) and biopsy help differentiate.
6. INVESTIGATIONS & DIAGNOSIS¶
Diagnosis involves imaging (CT/MRI), urine analysis, and biopsy. Staging uses AJCC TNM criteria. Molecular testing identifies actionable targets (e.g., MET, VHL).
6.1 Imaging¶
CT abdomen/pelvis with contrast, chest X-ray, and MRI for renal vein/IVC involvement. MRI preferred for patients with renal insufficiency. Ultrasound may detect large masses.
6.2 Laboratory Tests¶
Urinalysis (hematuria, proteinuria), serum calcium (hypercalcemia), and renal function tests. Cytokine levels (e.g., IL-6) may indicate advanced disease.
6.3 Staging¶
AJCC TNM system (Fig. 90-1). Stage I ( ≤ 7 cm, confined to kidney), Stage II (>7 cm), Stage III (invades Gerota’s fascia/lymph nodes), Stage IV (distant metastases).
7. MANAGEMENT & TREATMENT¶
Localized RCC is managed with nephrectomy (radical/partial). Metastatic disease uses targeted therapies (TKIs, mTOR inhibitors) and immunotherapy (checkpoint inhibitors).
7.1 Localized Disease¶
Radical nephrectomy (en bloc removal of kidney and Gerota’s fascia) or partial nephrectomy (preserves renal function). Partial nephrectomy preferred for small tumors (<4 cm) or solitary kidneys.
7.2 Metastatic Disease¶
First-line: VEGF/TKIs (sunitinib, pazopanib), mTOR inhibitors (everolimus). Second-line: Immunotherapy (nivolumab, pembrolizumab), combinations (e.g., nivolumab + ipilimumab, cabozantinib + nivolumab).
7.3 Adjuvant Therapy¶
Cytokines (interleukin-2, interferon- α ) and checkpoint inhibitors (pembrolizumab) for high-risk patients. Active surveillance for low-risk cases.
8. PROGNOSIS & COMPLICATIONS¶
5-year survival: 77% for localized RCC, <10% for distant metastases. Prognostic factors include stage, performance status, and biomarkers (e.g., IMDC score).
8.1 Survival Rates¶
77% 5-year survival for localized disease. Stage IV survival <10%. IMDC score (poor performance status, high calcium, neutrophils, platelets) predicts outcomes.
8.2 Complications¶
Chronic kidney disease, cardiovascular morbidity, treatment-related toxicity (e.g., hypertension, proteinuria), and metastatic spread.
9. SPECIAL CONSIDERATIONS¶
Pregnancy: Avoid nephrectomy unless urgent. Pediatrics: SMARCB1-deficient RCC associated with sickle cell trait. Elderly: Consider renal function and comorbidities. Genetic counseling for hereditary syndromes.
9.1 Pregnancy¶
Avoid nephrectomy unless life-threatening. Use of TKIs/immunotherapy during pregnancy is contraindicated.
9.2 Pediatrics¶
SMARCB1-deficient RCC is rare, aggressive, and linked to sickle cell trait. Early detection and multidisciplinary management are critical.
10. KEY POINTS & CLINICAL PEARLS¶
- Clear cell RCC is the most common subtype, driven by VHL/PBRM1/BAP1 mutations. 2. Metastatic RCC is treated with VEGF/TKIs, mTOR inhibitors, and immunotherapy. 3. Staging (AJCC TNM) guides treatment decisions. 4. Partial nephrectomy preserves renal function in low-risk cases. 5. IMDC score helps predict outcomes in metastatic disease.