familial renal oncocytoma

Familial Renal Oncocytoma: A Rare Genetic Disorder

Familial renal oncocytoma is a rare genetic disorder characterized by the development of benign tumors in the kidneys, known as renal oncocytomas. This condition is typically inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition.

Key Features:

• Benign Tumors: Renal oncocytomas are non-cancerous growths that can occur in one or both kidneys.
• Multiple and Bilateral: In affected family members, renal oncocytomas are often multiple and bilateral, meaning they occur in both kidneys.
• No Metastatic Disease: No metastatic disease (cancer spread) has been observed in individuals with familial renal oncocytoma.

Prevalence:

While the exact prevalence of familial renal oncocytoma is unknown, it is considered a rare condition. The number of reported cases is limited, and more research is needed to fully understand this disorder.

References:

• [1] In affected family members renal oncocytomas were often multiple and bilateral. No metastatic disease was observed. Most renal oncocytomas were detected in individuals with familial renal oncocytoma.[2]
• [3] Renal oncocytoma is a noncancerous (benign) growth in one or both of your kidneys.
• [4] In affected family members renal oncocytomas were often multiple and bilateral. No metastatic disease was observed. Most renal oncocytomas were detected in individuals with familial renal oncocytoma.[5]
• [6] Oncocytoma is the most common benign solid renal tumor and accounts for 3-7% of all primary renal neoplasms.
• [9] Renal oncocytoma is a benign renal epithelial neoplasm, that comprises approximately 5-7% of renal tubular epithelial tumors.

Familial renal oncocytoma, also known as hereditary oncocytoma, is a rare genetic disorder characterized by the growth of benign tumors in the kidneys. While these tumors are typically non-cancerous, they can still cause various signs and symptoms.

Common Signs and Symptoms:

• Abdominal or flank pain: Some people with familial renal oncocytoma may experience pain in the abdominal or flank area due to the growing tumor [4].
• Blood in the urine (hematuria): Hematuria is a common symptom of renal oncocytoma, where blood appears in the urine [5].
• Abdominal mass: A palpable abdominal mass can be felt upon examination, indicating the presence of a tumor [4].

Other Possible Symptoms:

• Flank pain: Pain in the flank area, which is the side of the body between the ribs and hip, may also occur due to the growing tumor [5].
• Blood in the urine (hematuria): As mentioned earlier, hematuria can be a symptom of renal oncocytoma.

Important Note: It's essential to note that not everyone with familial renal oncocytoma will experience symptoms. In some cases, the tumors may grow and cause problems without any noticeable signs or symptoms [3].

References: [1] Mar 2, 2022 — Skin growths: Non-cancerous lesions in the hair follicles of the face, neck and chest called fibrofolliculomas · Kidney growths: An increased ... [4] Some people with Renal oncocytoma will have abdominal or flank pain; blood in the urine; and/or an abdominal mass. Although these tumors can occur in people of ... [5] Possible signs and symptoms of a renal oncocytoma include blood in the urine, flank pain, and an abdominal mass. [8] Jun 28, 2022 — About one third of patients have signs and/or symptoms, with flank/abdominal pain, hematuria, and/or a flank mass among the most common.

Diagnosing Familial Renal Oncocytoma

Familial renal oncocytoma, a rare and benign kidney tumor, can be challenging to diagnose. The diagnostic process involves a combination of imaging tests, genetic studies, and histopathological examination.

• Imaging Tests: Computed tomography (CT) or magnetic resonance imaging (MRI) scans are commonly used to detect renal oncocytomas. However, these tests cannot reliably distinguish between oncocytoma and malignant renal neoplasms [8].
• Genetic Evaluation: Genetic studies such as karyotyping, comparative genomic hybridization (CGH), and mutational screening for selected exons of the c-MET gene tyrosine kinase receptor are used to identify genetic mutations associated with familial renal oncocytoma [3][6]. If PRCCs have been detected in a familial setting, the genetic testing should include mutational screening for selected exons (16–19) of the c-MET gene tyrosine kinase receptor [7].
• Histopathological Examination: A tissue sample from the tumor is taken and studied under a microscope to confirm the diagnosis. The histopathological features of renal oncocytoma, such as a well-circumscribed tan or mahogany-colored mass with a stellate central scar, can help differentiate it from other kidney tumors [10].

Key Points

• Imaging tests are not reliable for distinguishing between oncocytoma and malignant renal neoplasms.
• Genetic studies can identify genetic mutations associated with familial renal oncocytoma.
• Histopathological examination is essential to confirm the diagnosis of renal oncocytoma.

References:

[3] by F Trevisani · 2022 · Cited by 16 — Genetic Evaluation. In the routine clinical differential diagnosis of a renal cell carcinoma suspected of being an oncocytoma, genetic studies such as karyotyping, comparative genomic hybridization (CGH), and mutational screening for selected exons of the c-MET gene tyrosine kinase receptor are used to identify genetic mutations associated with familial renal oncocytoma.

[6] by F Trevisani · 2022 · Cited by 16 — In the routine clinical differential diagnosis of a renal cell carcinoma suspected of being an oncocytoma, genetic studies such as karyotyping, comparative genomic hybridization (CGH), and mutational screening for selected exons of the c-MET gene tyrosine kinase receptor are used to identify genetic mutations associated with familial renal oncocytoma.

[7] If PRCCs have been detected in a familial setting, the genetic testing should include mutational screening for selected exons (16–19) of the c-MET gene tyrosine kinase receptor.

[8] A meta-analysis of 205 oncocytic renal mass biopsies from 2017 showed that the positive predictive value for a diagnosis of oncocytoma on renal mass biopsy was 67% with significant heterogeneity and wide confidence interval, indicating that the diagnostic accuracy varies greatly between studies and, by extrapolation, between pathologists.

[10] A well-circumscribed tan or mahogany-colored mass with a stellate central scar is a characteristic histopathological feature of renal oncocytoma.

Treatment Options for Familial Renal Oncocytoma

Familial renal oncocytoma, a rare genetic disorder, can increase the risk of developing kidney cancer. While there is no specific treatment for this condition, targeted therapies have shown promise in managing related cancers.

• VEGF and mTOR pathway inhibitors: These drugs, such as sunitinib and everolimus, are commonly used to treat advanced renal cell carcinoma (RCC). Research suggests that they may also be effective in treating familial RCC syndromes, including oncocytoma [5][6].
• Genetic testing: Early detection of familial renal cancer through genetic testing can enable timely use of these targeted therapies, potentially improving treatment outcomes [14].

Other Treatment Considerations

While there is no specific treatment for familial renal oncocytoma, the following approaches may be considered:

• Active surveillance: Monitoring with imaging tests (CT, MRI or ultrasound) may be recommended if the mass is very small.
• Tumor ablation: This minimally invasive procedure can be used to treat small tumors.

References

[5] by PJ Morrison · 2010 · Cited by 31 — ... drugs is improving treatment in this area [35]. VEGF-inhibiting drugs include sunitinib, sorafenib, and bevacizumab. The latter is a monoclonal antibody ...

[6] by EA Singer · 2012 · Cited by 62 — This article reviews recent developments in the use of systemic targeted therapies for the treatment of advanced clear and non-clear cell renal cell carcinoma ( ...

The differential diagnosis of familial renal oncocytoma involves distinguishing it from other neoplasms that may present with similar characteristics.

• Chromophobe RCC: This is a type of kidney cancer that can be difficult to distinguish from oncocytoma, particularly in its eosinophilic variant [6][8]. Chromophobe RCC typically has a more aggressive behavior than oncocytoma.
• Renal cell carcinoma (RCC): As mentioned in [7], the differential diagnosis of oncocytoma includes other neoplasms with eosinophilic or oncocytic cytoplasm, such as RCC. However, oncocytoma is generally considered a benign tumor.
• Low-grade oncocytic tumors: These are a family of renal neoplasia that can include oncocytoma and other similar tumors [9]. The differential diagnosis of familial renal oncocytoma may involve distinguishing it from these low-grade oncocytic tumors.

It's worth noting that the clinical importance of distinguishing oncocytoma from other neoplasms lies in the difficulty in distinguishing it from RCC, which can have more aggressive behavior [8].

References: [6] Jun 28, 2022 — The differential diagnosis of oncocytoma includes other neoplasms with eosinophilic or oncocytic cytoplasm and primarily chromophobe RCC, as ... [7] by F Trevisani · 2022 · Cited by 16 — In the routine clinical differential diagnosis of a renal cell carcinoma suspected of being an oncocytoma, genetic studies such as karyotyping, comparative ... [8] Nov 19, 2024 — Renal oncocytomas are relatively benign renal tumors. This lesion's main clinical importance is the difficulty in distinguishing it from renal cell carcinoma. [9] by MB Amin · 2022 · Cited by 17 — In this review, we present a practical clinically relevant algorithmic approach to classifying tumors within the low grade oncocytic family of renal neoplasia.