CONTEXT: Nonneoplastic changes are often identified in
nephrectomy specimens removed for
renal neoplasms. Although they may be of
prognostic or therapeutic importance, they are often overlooked.
Nephrectomy is also performed for nonneoplastic
lesions, the most frequent of which are
urinary obstruction and
end-stage renal disease, but the tissue diagnosis of these conditions and the implicated clinicopathologic
correlation may not be well appreciated. OBJECTIVE: To outline these nonneoplastic
lesions with special attention to important diagnostic caveats and clinicopathologic
correlations. DATA SOURCES: The presented information was
derived from literature, personal experience, and review of case materials at the authors' institutions. RESULTS: Nonneoplastic
lesions are seen in most (90%)
nephrectomy specimens removed for
renal neoplasms. Although these
lesions span the spectrum of "medical"
kidney diseases, the most frequent of them are
hypertensive nephrosclerosis and
diabetic nephropathy. Recognition of these diseases is important because they are often first diagnosed and later confirmed clinically. Furthermore, the severity of these
lesions may predicate both short- and long-term
renal function and thus help guide treatment. Among conditions that necessitate
nephrectomy, advanced
urinary obstruction,
end-stage renal disease, and
end-stage renal disease with
acquired cystic changes are probably the most frequent. These conditions have characteristic morphologic features, but they may be associated with superimposing
lesions previously not well described. These superimposing
lesions may create diagnostic
confusion; yet, some of them are the reason for
nephrectomy. Thus, acute
bacterial infection,
urine polyp,
granulomatous pyelitis, papillary
necrosis, massive
bleeding, and
renal dysplasia can develop against the background of obstructive
nephropathy.
Renal neoplasms may develop from the background of
end-stage renal disease without
cystic changes. A
renal neoplasm or massive
bleeding with or without
neoplasm is usually the reason for
nephrectomy in
kidney with
acquired cystic kidney diseases. Thus, while nonneoplastic changes are frequent in
nephrectomy specimens, they are often unrecognized.
Awareness of these conditions and a familiarity with their diagnostic features as well as the implicated clinicopathologic
correlation should help obviate this diagnostic problem.
