Ancillary Diagnostic Techniques in the Evaluation of Adult Epithelial Renal Neoplasms

Abstract

The role played currently by the different ancillary diagnostic techniques in the diagnosis of adult epithelial renal tumors continues to be debated. It has also become clear that in some instances light microscopic appearance alone cannot be used to classify these neoplasms into specific categories with the degree of precision required for therapeutic purposes. Renal cell carcinoma (RCC) subtypes may share common histologic characteristics but exhibit different biological behavior and response to therapy which clearly indicates the crucial role that advanced pathologic speciation plays in the current assessment of these neoplasms. Although immunohistochemistry is widely used for the purpose of categorizing renal tumors because of its widespread availability, the immunoprofiles of the various types of renal neoplasms overlap significantly, making definitive diagnostic determinations difficult and challenging at times. This manuscript will address how ancillary diagnostic techniques can be incorporated into the routine evaluation of neoplastic renal masses to improve classification. Both cytology and surgical specimens will be addressed, as fine needle aspiration (FNA) is being used with preference in many cases in the diagnosis of renal masses. Surgical and cytopathologists must intelligently select the ancillary diagnostic technique/s that will provide the information needed to solve the differential diagnosis under consideration in a given case. However, in some cases >1 of these techniques should be used to make an accurate diagnosis with the aim of arriving at an unequivocal diagnosis. The identification of specific signaling pathways that are defective in certain types of renal neoplasms has made possible the design of target-specific therapies that are directed towards the aberrant pathways associated with the defective proteins found in these tumors. This makes the exact classification of these neoplasms and the detection of these aberrant proteins targeted for treatment an absolute requirement for the application of these molecular-based therapeutic interventions. The role that the pathologic assessment plays in the classification of renal tumors becomes more important than ever to take advantage of this and similar new molecular-oriented therapies.

Histological and immunohistochemical characterization of feline renal cell carcinoma: a case series

“…In human medicine, RCCs with proximal tubular differentiation express CD10, whereas those with distal tubular differentiation express kidney-specific cadherin. Additionally, it has been proposed that, while conventional RCCs are closely related to mature proximal ECs, papillary subtype is more similar to embryonal proximal tubular cells [ 16 ]. In our cases, 2 tubular RCCs were E-CAD positive and CD10 negative, confirming the distal convoluted tubule origin.…”

Ancillary studies in fine needle aspiration of the kidney

“…Nevertheless, in the past decade pathologists have acquired more knowledge, especially regarding individual subtypes of RCC. [1][2][3][4] Many of these newer subtypes of RCC either require or are much easier to diagnose with additional ancillary testing, [4][5][6][7][8][9][10][11][12][13][14][15][16] and increasingly tumors with mixed features are being recognized. 17,18 No specific prognostic markers are available for RCC, although the correct identification of the specific subtype of RCC does more clearly define the prognosis of the patient.…”

Exploring Multiphoton Microscopy as a Novel Tool to Differentiate Chromophobe Renal Cell Carcinoma From Oncocytoma in Fixed Tissue Sections

“…However, given that oncocytoma is a benign tumor with excellent prognosis, whereas chRCC is a malignant tumor with metastatic potential, 3 such distinction is critically important for the clinical management of patients. Consequently, when a pathologist is faced with a diagnostic challenge on H&E, he or she relies on a battery of ancillary techniques, 4,5 including immunohistochemistry, 6 electron microscopy, [7][8][9] and cytogenetic analysis, 10,11 to arrive at a definitive diagnosis. Although these techniques have proven to be helpful, none of them are highly specific, and they have overlapping characteristics.…”