Renal oncocytoma other diagnostic studies: Difference between revisions
Homa Najafi (talk | contribs) No edit summary |
Homa Najafi (talk | contribs) |
||
| Line 79: | Line 79: | ||
Such observational treatment may be entirely appropriate for patients at poor operative risk because of | Such observational treatment may be entirely appropriate for patients at poor operative risk because of | ||
extensive comorbidities | extensive comorbidities | ||
Renal mass biopsy (RMB) was abandoned due to several | |||
shortcomings of the procedure. It was claimed that RMB | |||
may be inaccurate due to sampling errors and heterogeneity | |||
of renal masses. As stated above, on some occasions it is | |||
difficult to distinguish between oncocytoma, cRCC, and | |||
oncocytic papillary RCC. In addition, the “hybrid” nature of | |||
some tumors may be missed by RMB. Despite these limitations, | |||
the positive and negative predictive values of RMB | |||
are quite high (95.7% and 82%, respectively). Similarly, | |||
sensitivity and specificity were also high (92.1% and 89.7%, | |||
respectively). Another concern raised in the past was the | |||
pretty high complication rate [80]. Recent studies demonstrated | |||
less than 5% minor complications, mostly peri-renal | |||
hemorrhage [80–83], however only 1% to 2% required | |||
observation or blood transfusion [84]. High needle approach | |||
to upper pole tumors may pierce through the pleura in 14% | |||
to 29% [85], but clinically evident pneumothorax occurs in | |||
less than 1% of cases [85]. Tumor seeding was a feared | |||
complication of RMB, but its reported incidence is less than | |||
0.01% and no case was reported in the last 15 years [86]. | |||
Evidently, RMB has some disadvantages, but the risk of | |||
overtreating patients by avoiding RMB became recently a | |||
discussed issue that received new interest. Reluctance of | |||
patients to undergo and physicians to prescribe nonsurgical | |||
treatment for renal masses without definitive tissue diagnosis | |||
could be alleviated by RMB. Technological innovations (e.g., introducers, higher quality imaging) will probably | |||
make RMB safer and more accurate. | |||
Core needle biopsies are increasingly used in the diagnosis | |||
of renal masses (Figure 3). Because 20–45% of small renal | |||
masses are ultimately found to be benign, active surveillance | |||
is an option for many patients (38, 39). The diagnostic accuracy | |||
of renal mass biopsy remains somewhat controversial, | |||
however. Individual groups have reported up to 80% diagnostic | |||
rate from renal mass biopsy, with the ability to provide | |||
subtype and nuclear grade in the majority of diagnostic biopsies | |||
(40). | |||
Unfortunately, oncocytic lesions can be especially troublesome | |||
in renal mass biopsy, as interpreting only a limited sampling | |||
of tumor may not be representative of the entire lesion. | |||
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 (41). | |||
For renal mass biopsies of oncocytic neoplasms, there is a | |||
split among urologic pathologists as to whether it is preferable | |||
to issue an outright diagnosis of oncocytoma (when features | |||
are typical in the biopsy sample) or to use more general | |||
terminology, such as “oncocytic neoplasm,” with comment that the features are compatible with oncocytoma (5). In the | |||
context that morphologic and immunohistochemical features | |||
are largely compatible with oncocytoma, yet in which there | |||
are minor equivocal features, such as variation in cell size | |||
or slight nuclear irregularity, it is also reasonable to utilize | |||
a borderline diagnostic category expressing uncertainty between | |||
oncocytoma and eosinophilic variant chromophobe | |||
renal cell carcinoma. In this setting, immunohistochemical | |||
staining may also be helpful. Although CK7 staining may not | |||
be beyond the expected level of oncocytoma, findings such as | |||
negative vimentin staining and positive KIT staining generally | |||
argue against other considerations, such as papillary or | |||
clear cell renal cell carcinoma with eosinophilic cells. Since | |||
chromophobe renal cell carcinoma, especially the eosinophilic | |||
variant, is also generally regarded as a less aggressive | |||
tumor subtype, this can facilitate appropriate management in | |||
patients who are candidates for nonsurgical treatment (42). | |||
Conversely, if nuclear or cytologic features are inconsistent | |||
with oncocytoma (non-degenerative atypia, nuclear membrane | |||
irregularity, or perinuclear clearing), a diagnosis of eosinophilic | |||
variant of chromophobe renal cell carcinoma may | |||
be favored. | |||
==References== | ==References== | ||
{{reflist|2}} | {{reflist|2}} | ||
Revision as of 14:03, 14 May 2019
|
Renal oncocytoma Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Renal oncocytoma other diagnostic studies On the Web |
|
American Roentgen Ray Society Images of Renal oncocytoma other diagnostic studies |
|
Risk calculators and risk factors for Renal oncocytoma other diagnostic studies |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Homa Najafi, M.D.[2]
Overview
There are no other diagnostic study findings associated with renal oncocytoma.
Other Diagnostic Studies
There are no other diagnostic study findings associated with renal oncocytoma.
Overview
There are no other diagnostic studies associated with [disease name].
OR
[Diagnostic study] may be helpful in the diagnosis of [disease name]. Findings suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].
OR
Other diagnostic studies for [disease name] include [diagnostic study 1], which demonstrates [finding 1], [finding 2], and [finding 3], and [diagnostic study 2], which demonstrates [finding 1], [finding 2], and [finding 3].
Other Diagnostic Studies
There are no other diagnostic studies associated with [disease name].
OR
[Diagnostic study] may be helpful in the diagnosis of [disease name]. Findings suggestive of/diagnostic of [disease name] include:
- [Finding 1]
- [Finding 2]
- [Finding 3]
OR
Other diagnostic studies for [disease name] include:
- [Diagnostic study 1], which demonstrates:
- [Finding 1]
- [Finding 2]
- [Finding 3]
- [Diagnostic study 2], which demonstrates:
- [Finding 1]
- [Finding 2]
- [Finding 3]
Equivocal results from multiple studies investigating the use of percutaneous renal biopsy have resulted in its limited role in the diagnosis of solid renal masses. A recent small retrospective series from MD Anderson Cancer Center examined fine needle aspiration cytology of eosinophilic renal neoplasms with special stains (eg, cytokeratin, vimentin, and Hale’s colloidal iron) and electron microscopy (in selected cases), demonstrating some success in predicting final pathology [18]. However, the value of this study was limited because of its retrospective nature and the lack of surgical specimens to provide “gold standard” data from a significant number of patients felt to have oncocytoma. Frozen-section needle biopsy performed at time of renal exploration failed to yield reliable diagnoses in a recent prospective study from our institution [41]. One hundred three patients underwent radical or partial nephrectomy for their renal tumors. After resection, a “back table” biopsy was obtained from each tumor using an 18-gauge biopsy gun and sent for frozen section. Two urologic pathologists independently reviewed the specimens, and the results were compared with those from whole-mount permanent sections. Overall accuracy of the two pathologists was 76% and 80%, respectively, with nondiagnostic rates of 11% and 17%. Both pathologists diagnosed 5% of the malignant lesions as benign, and 21% and 36% of benign lesions as malignant. The quality of the biopsies themselves was clearly ideal and not subject to the vagaries inherent in percutaneous biopsies. Needle biopsy of the tumor can be a useful strategy to diagnose oncocytoma in the very elderly or very sick patient with a renal tumor. There have been cases reported in which patients with large bilateral and unresectable renal oncocytomas have been observed for many years without showing distinct tumoral progression. Such observational treatment may be entirely appropriate for patients at poor operative risk because of extensive comorbidities
Renal mass biopsy (RMB) was abandoned due to several shortcomings of the procedure. It was claimed that RMB may be inaccurate due to sampling errors and heterogeneity of renal masses. As stated above, on some occasions it is difficult to distinguish between oncocytoma, cRCC, and oncocytic papillary RCC. In addition, the “hybrid” nature of some tumors may be missed by RMB. Despite these limitations, the positive and negative predictive values of RMB are quite high (95.7% and 82%, respectively). Similarly, sensitivity and specificity were also high (92.1% and 89.7%, respectively). Another concern raised in the past was the pretty high complication rate [80]. Recent studies demonstrated less than 5% minor complications, mostly peri-renal hemorrhage [80–83], however only 1% to 2% required observation or blood transfusion [84]. High needle approach to upper pole tumors may pierce through the pleura in 14% to 29% [85], but clinically evident pneumothorax occurs in less than 1% of cases [85]. Tumor seeding was a feared complication of RMB, but its reported incidence is less than 0.01% and no case was reported in the last 15 years [86]. Evidently, RMB has some disadvantages, but the risk of overtreating patients by avoiding RMB became recently a discussed issue that received new interest. Reluctance of patients to undergo and physicians to prescribe nonsurgical treatment for renal masses without definitive tissue diagnosis could be alleviated by RMB. Technological innovations (e.g., introducers, higher quality imaging) will probably make RMB safer and more accurate.
Core needle biopsies are increasingly used in the diagnosis of renal masses (Figure 3). Because 20–45% of small renal masses are ultimately found to be benign, active surveillance is an option for many patients (38, 39). The diagnostic accuracy of renal mass biopsy remains somewhat controversial, however. Individual groups have reported up to 80% diagnostic rate from renal mass biopsy, with the ability to provide subtype and nuclear grade in the majority of diagnostic biopsies (40). Unfortunately, oncocytic lesions can be especially troublesome in renal mass biopsy, as interpreting only a limited sampling of tumor may not be representative of the entire lesion. 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 (41). For renal mass biopsies of oncocytic neoplasms, there is a split among urologic pathologists as to whether it is preferable to issue an outright diagnosis of oncocytoma (when features are typical in the biopsy sample) or to use more general terminology, such as “oncocytic neoplasm,” with comment that the features are compatible with oncocytoma (5). In the context that morphologic and immunohistochemical features are largely compatible with oncocytoma, yet in which there are minor equivocal features, such as variation in cell size or slight nuclear irregularity, it is also reasonable to utilize a borderline diagnostic category expressing uncertainty between oncocytoma and eosinophilic variant chromophobe renal cell carcinoma. In this setting, immunohistochemical staining may also be helpful. Although CK7 staining may not be beyond the expected level of oncocytoma, findings such as negative vimentin staining and positive KIT staining generally argue against other considerations, such as papillary or clear cell renal cell carcinoma with eosinophilic cells. Since chromophobe renal cell carcinoma, especially the eosinophilic variant, is also generally regarded as a less aggressive tumor subtype, this can facilitate appropriate management in patients who are candidates for nonsurgical treatment (42). Conversely, if nuclear or cytologic features are inconsistent with oncocytoma (non-degenerative atypia, nuclear membrane irregularity, or perinuclear clearing), a diagnosis of eosinophilic variant of chromophobe renal cell carcinoma may be favored.