Interinstitutional comparison of frozen section consultation in small hospitals: a College of American Pathologists Q-Probes study of 18,532 frozen section consultation diagnoses in 233 small hospitals.

OBJECTIVE: To study pathology intraoperative consultation practices and the accuracy of diagnoses made by frozen section. DESIGN: In 1994, participants in the College of American Pathologists Q-Probes laboratory quality improvement program each completed questionnaires and prospectively collected data on up to 20 frozen section procedures performed over a 5-month period. SETTING: Surgical pathology laboratories serving private and public hospitals with 300 or fewer occupied beds. PARTICIPANTS: Two hundred thirty-two North American institutions and one New Zealand institution. MAIN OUTCOME MEASURES: The discordance and deferral rates of frozen section diagnoses and the reasons for frozen section discordance relative to corresponding diagnoses made on permanent (paraffin) sections. Calculation of frozen section discordance rates excluded diagnoses of subtypes or grade of malignancy, biopsies on specimens in which there was no gross lesion (eg, mammographic specimens), thyroid follicular lesions, tissue taken only to determine adequacy for other studies (eg, estrogen-binding proteins), and frozen sections performed to evaluate margins of specimens oriented en face. RESULTS: Out of 18,532 frozen section diagnoses performed on 327,884 surgical cases, 859 (4.6%) diagnoses were deferred until permanent sections were available for review; 17,357 (98.2%) nondeferred diagnoses agreed with, and 316 (1.8%) disagreed with, those diagnoses rendered on permanent sections. The most common cause of discordance was underdiagnosis of neoplasia, usually due to block- or tissue-sampling errors. CONCLUSIONS: We recommend that laboratories routinely monitor frozen section discordance, cut additional sections deeper into the frozen block and/or sample additional tissue when the initial frozen section diagnosis is negative or nonproductive, reconcile all discordant frozen section diagnoses in the final report, and periodically assess the value of performing frozen section examinations.

Extraneous tissue in surgical pathology: a College of American Pathologists Q-Probes study of 275 laboratories.

OBJECTIVE: To develop a multi-institutional reference database of extraneous tissue (contaminants) in surgical pathology. DESIGN: In 1994, participants in the College of American Pathologists Q-Probes quality improvement program performed prospective and retrospective evaluations of extraneous tissue found in surgical pathology microscopic sections for a period of 4 weeks or until 1000 slides were reviewed in each participating laboratory. PARTICIPANTS: Two hundred seventy-five surgical pathology laboratories institutions, predominantly from North America. MAIN OUTCOME MEASURES: Extraneous tissue contamination rate for slides in prospective and retrospective reviews; staffing and practice procedures; location of extraneous tissue on slides; type of extraneous tissue (normal, abnormal, nonneoplastic, neoplasm, microorganisms, etc); class of extraneous tissue (slide or block contaminants); source of extraneous tissue (different or same case); origin of extraneous tissue (pathology laboratory, physician's office or operating room); and degree of diagnostic difficulty caused by extraneous tissue. RESULTS: Three hundred twenty-one thousand seven hundred fifty-seven slides were reviewed in the prospective study and 57083 slides in the retrospective study. There was an overall extraneous tissue rate of 0.6% of slides (2074/321757) in the prospective study and 2.9% of slides (1653/57083) in the retrospective study. Of those slides with extraneous tissue, the extraneous tissue was located near diagnostic tissue sections in 59.5% of the slides reviewed prospectively and in 25.3% of slides reviewed retrospectively; deeper sections were performed to evaluate extraneous tissue in 12.2% of prospective cases and in 3.1% of retrospective cases. Of the laboratories, 98% had written guidelines for changing solution in tissue processors, and 64.9% had guidelines for maintaining water baths free of extraneous tissue. A total of 98.9% used lens paper, filter bags, or sponges for processing fragmented and small specimens. Written protocols for documentation of extraneous tissue in surgical pathology reports were established in 6.1% of laboratories, for removal of extraneous tissue from blocks in 5.7%, and for removal of extraneous tissue from microscopic slides in 4.7%. In 24% of laboratories no comment or record was kept to document extraneous tissue. Extraneous tissue consisted of neoplasm in 12.7% of the prospectively reviewed slides and in 6.0% of the retrospectively reviewed slides. For the prospective study, 59.4% of extraneous tissue was classified as slide contaminants, and 28.4% was found to be contaminants within the paraffin block; for the retrospective study, 72.9% was classified as slide contaminants and 15.9% as block contaminants. For the prospective study, 63.2% of extraneous tissue was presumed to be from a different case, and in the retrospective study, 48.5% was presumed to be from a different case. Over 90% of extraneous tissue was thought to originate from the pathology laboratory. The degree of diagnostic difficulty caused by extraneous tissue was judged to be severe in 0.4% of slides in the prospective study and 0.1% of slides in the retrospective study. In the prospective study, it could not be determined whether the tissue in the diagnostic sections was extraneous in 0.6% of slides, and in the retrospective study, it could not be determined whether tissue in the diagnostic sections was extraneous in 0.1%. CONCLUSIONS: This study has documented the frequency, type, origin, source, and diagnostic difficulty of extraneous tissue and presents benchmarks of extraneous tissue experienced in the general practice of surgical pathology.

Lung carcinoma surgical pathology report adequacy: a College of American Pathologists Q-Probes study of over 8300 cases from 464 institutions.

OBJECTIVE: To assess the adequacy of reporting gross and microscopic pathologic findings of resected lung carcinoma. DESIGN: Q-Probes study following the College of American Pathologists format. SETTING: Pathology laboratories, 1991. PARTICIPANTS: Four hundred sixty-four institutions. MAIN OUTCOME MEASURES: Rate of reporting gross and microscopic features. RESULTS: Information provided in over 8300 surgical pathology reports of resected primary lung carcinomas from 464 institutions was reviewed. Descriptors included gross and microscopic findings. The rate of reporting the descriptors from the aggregate sample is listed as follows (the corrected rate for those descriptors in which evaluation was not applicable are listed in parentheses for each descriptor where appropriate): general findings, standard report or checklist used 20.8%, type of procedure stated 89.6%, and lobe or lung of origin stated 99.1% (99.5%); gross findings, distance of neoplasm from nearest visceral pleura 61.1%, involvement or lack of involvement of bronchus 68.7%, presence or absence of involvement of veins 18.3%, parenchyma not involved by neoplasm described 80.1% (81.4%), visceral pleural surface described 83.0%, tumor size stated 97.2%, and description of regional lymph nodes attached to specimen 74.7% (82.7%); and microscopic findings, microscopic description 77.6%, histologic type of tumor stated 99.3%, grade of carcinoma stated 80.9% (88.7%), presence or absence of lymphatic vascular invasion 24.3%, status of lymph nodes stated 89.0% (95.9%), presence or absence of venous invasion 22.6%, presence or absence of neoplasm at bronchial margin 90.8%, presence or absence of neoplasm at vascular margin 30.9%, presence or absence of carcinoma in the visceral pleura 64.6% (66.9%), and presence or absence of abnormality in nonneoplastic parenchyma 72.8% (74.1%). CONCLUSION: The rate of reporting gross and microscopic features varies; recommendations for reporting are made and include the use of a standard report form or checklist.

Renal pathology in patients with primary hyperaldosteronism secondary to an adrenal cortical adenoma.

OBJECTIVES: The cause of persistent hypertension following the removal of an aldosterone-producing adrenal adenoma is unknown. The purpose of this study was to determine whether this occurrence is due to existing renal histopathologic damage. METHODS: Thirty-two patients with primary hyperaldosteronism due to an aldosterone-secreting adrenal cortical adenoma underwent open renal biopsy at the time of unilateral adrenalectomy. Biopsy results were correlated with the duration and severity of hypertension before and after surgery. RESULTS: Nineteen patients were cured of their hypertension postoperatively, whereas 13 patients had persistent diastolic hypertension. Statistical analysis of these two groups revealed no difference when renal histopathologic variables, preoperative severity of hypertension, or preoperative duration of hypertension were compared. CONCLUSIONS: Persistent hypertension in these patients does not appear to be due to renal histopathologic changes; coexisting essential hypertension is a more likely cause.

Interinstitutional comparison of frozen section consultations. A college of American Pathologists Q-Probes study of 90,538 cases in 461 institutions.

OBJECTIVE: To assess concordant, discordant, and deferred diagnosis rates from frozen sections; to determine reasons for discordance; to identify pathologic processes associated with discordant diagnoses; to determine false-positive or false-negative rates for neoplasms; and to identify anatomic sites associated with discordant frozen section diagnoses. DESIGN: Q-Probes study of the College of American Pathologists. PARTICIPANTS: Four hundred sixty-one institutions participating in the Q-Probes program from November 1, 1990, through March 31, 1991. MAIN OUTCOME MEASURES: Concordant and discordant diagnosis rates. RESULTS: The frozen section concordance rate for diagnoses from the aggregate group was 98.58% and the discordance rate was 1.42%, when uncorrected for deferred diagnoses. During the study period, participating institutions accessioned 1,693,331 surgical pathology cases; 90,538 of these cases were evaluated by frozen section consultation, resulting in the examination of 121,668 specimens and 148,506 frozen section blocks. The majority of the frozen section discordances occurred because of misinterpretation of the original frozen section (31.8%), presence of diagnostic tissue in permanent sections of the frozen block when the frozen section was negative (30.0%), and presence of diagnostic tissue in the portion of the specimen not sampled by the frozen section (31.4%). Of the discordant diagnoses, 67.8% had false-negative diagnoses for neoplasm. The pathology processes and anatomic sites represented in discordant diagnoses are also evaluated. CONCLUSIONS: High diagnostic accuracy of frozen section consultations was demonstrated. Frozen sections are used to evaluate a variety of pathologic processes and anatomic sites.

Intralaboratory timeliness of surgical pathology reports. Results of two College of American Pathologists Q-Probes studies of biopsies and complex specimens.

OBJECTIVE: To develop multi-institutional reference databases for intralaboratory timeliness of surgical pathology routine biopsies and complex specimens from the time of specimen accessioning to report completion, and to examine the influence of laboratory characteristics and practices on turnaround time (TAT). DESIGN: Participants in the Q-Probes quality improvement program of the College of American Pathologists took part in two separate studies, the first conducted in 1992 and 1993 and the second in 1993 and 1994. Each participant tracked the number of days from specimen accessioning to report completion for 30 routine biopsies and 30 complex specimens in each study. Based on this intralaboratory time interval, performance was compared with the College of American Pathologists' laboratory accreditation standard of 2 working days. PARTICIPANTS: Five hundred twenty-five surgical pathology laboratories responded to the study of routine biopsies, and 489 laboratories responded to the study of complex specimens. Participants were mainly located in the United States, but there were respondents from Canada, Australia, New Zealand, and Hong Kong as well. RESULTS: In the first study, evaluation of 15 725 biopsy cases showed that the cumulative aggregate percentage of routine biopsy cases processed from the time of specimen accessioning to report completion was 79% by 1 working day, 95% by 2 working days, and 98% by 3 working days. Individual participant's data revealed that all reports were completed by the second working day in 90% of the laboratories and by the third working day in 95% of laboratories. Factors that significantly contributed to increased report TAT included larger institutional size, a greater number of surgical pathologists, greater annual surgical pathology volume processed, technical processing resulting in delayed slide availability, pathology practices that integrated residency training, and reduced staffing levels of histotechnologists/technicians and transcriptionists. Shorter TATs were achieved in those institutions that had previously established a TAT goal for routine biopsy specimens. In the second study of 14 298 aggregate complex specimen cases, 68% required routine processing and 32% required special handling. Overall, 56% of all complex specimen reports were processed and completed in 1 working day, 81% in 2 working days, 91% in 3 working days, and 95% in 4 working days. On average, the percentage of cases processed and reports signed out in 2 working days or less was 80% for all complex specimen cases, 90% for routine cases, and 60% for special-handling cases. The mean of all participants' median TATs was 1.5 days (range 0-5 days) for complex specimens, 1.3 days (range 0-5 days) for cases requiring routine handling, and 2.6 days (range 0-13.5 days) for cases requiring special handling. Several factors were associated with increased report TAT: institutional occupied bedsize greater than 450, routine responsibility for gross dissection assigned to residents only, earliest availability of slides after 12 pm, resident involvement in sign-out, interposing a day between availability of slides and final slide sign-out for resident education purposes, and a greater number of surgical pathologists. CONCLUSIONS: We have documented that for the majority of routine cases, the College of American Pathologists Laboratory Accreditation Program's TAT standard of report completion time within 2 working days for the intralaboratory component of TAT is a reasonable goal. This standard was successfully met by participants in 95% of routine biopsy cases and 91% of routine complex specimens. Special-handling procedures for complex specimens contributed, on average, an additional delay of 1.3 days. To our knowledge these are the first systematic studies to describe timeliness from the time of specimen accessioning to report completion for surgical pathology specimens, and they may serve as reference databases for benchm

Interinstitutional comparison of bladder carcinoma surgical pathology report adequacy. A College of American Pathologists Q-Probes Study of 7234 bladder biopsies and curettings in 268 institutions.

Participants in the 1992 College of American Pathologists' Q-Probes Study of bladder carcinoma surgical report adequacy evaluated 7234 bladder biopsies and curettings from 268 institutions. In over 98% of the cases evaluated, the histologic type was stated. In over 95%, the histologic grade was stated where appropriate. Of the 7234 cases studied, 2149 (29.7%) were invasive, 4498 (62.2%) were noninvasive, and invasiveness (presence or absence of invasion) was not stated for 587 (8.1%). For invasive carcinomas, there was definitive assessment for the presence or absence of muscularis propria in 1145 (53.3%) of 2149 cases, and in 67 (3.1%) of 2149 cases no muscle or muscularis was present. For noninvasive carcinomas, there was a definitive evaluation of the muscularis propria (presence or absence) in 1349 (30%) of 4498 cases.

Three-dimensional analysis of glomerular morphology in patients with subtotal nephrectomy.

Previous studies documented that single section examination of kidney tissue underestimates glomerulosclerosis and that three-dimensional examination of glomerular morphology improves recognition of the incidence and distribution of sclerotic changes within the glomerular capillary tuft. We have adopted this technique to evaluate the true frequency and the spatial extent of glomerulosclerosis in patients who were subjected to extensive renal mass reduction. We re-evaluated four kidney biopsies of patients with a solitary kidney who had undergone partial nephrectomy for renal-cell carcinoma. Histopathological examination aimed at detection of glomerular sclerotic lesions was performed on serial sections (from 75 to 93 serial sections for each biopsy, 3 microns thick) together with three-dimensional morphometric analysis of glomerular tuft and sclerotic areas using a computer-based image processing system. Results were compared with observations based on more conventional single section evaluation of the same biopsies. Among 65 glomeruli examined by three-dimensional morphometric analysis, only 8% were normal, 42% revealed segmental sclerosis and 51% global sclerosis. These results confirmed that single section evaluation grossly overestimates the number of normal glomeruli (37% vs. 8%, respectively), since the majority of glomeruli classified as normal are indeed affected by sclerotic changes in areas typically out of the section plane. The three-dimensional distribution of sclerosis is characterized by the appearance of multi-focal areas affecting a small capillary tuft volume (< 10%) which ultimately propagate to the entire capillary tuft. Despite the maintenance of renal function, at the time of biopsy in patients with extensive ablation of renal mass, the incidence of glomerulosclerosis affects almost the entire glomerular population.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic significance of flow cytometry in non-small-cell lung cancer.

To clarify the value of deoxyribonucleic acid (DNA) ploidy analysis, we prospectively studied single-parameter flow cytometric findings of fresh tissue from 272 patients with primary non-small-cell lung cancer from whom adequate tissue from the lung cancer was available. The mean age of the patients was 65.5 years; 65.8% were men. Histologic types were as follows: adenocarcinoma, 107 (39.3%); squamous cell, 100 (36.8%); large cell, 56 (20.6%); adenosquamous, 8 (2.9%); and giant cell, 1 (0.4%). Histologic grades were as follows: I (well differentiated), 15 (5.5%); II, 100 (36.8%); and III, 157 (57.7%). American Joint Committee on Cancer stages were as follows: I, 151 (55.5%); II, 38 (14%); III, 74 (27.2%); and IV, 9 (3.3%). Survivals at 1 year and 3 years were 74.2% +/- 2.8% and 52.4% +/- 4.8%, respectively. For non-squamous cell lung cancer, multivariate analyses with the Cox proportional hazards regression model for survival showed (1) that increasing American Joint Committee on Cancer stage (p < 0.001), male gender (p = 0.02), and histologic grades II and III (p = 0.04) were of independent (negative) prognostic significance and (2) that the presence and absence of DNA aneuploidy (p = 0.91), the classification of DNA histogram (p = 0.81), the DNA index (p = 0.46), and the results of cell cycle analysis in tumors with no aneuploidy (S phase, p = 0.23; S + G2M, p = 0.62) were of no prognostic significance. For squamous cell lung cancer, multivariate analyses showed that increasing American Joint Committee on Cancer stage (p = 0.003) and increasing DNA index (p = 0.009) were of independent (negative) prognostic significance.

Pseudo-gamma heavy chain (IgG4 lambda) deposition disease.

Two patients with Ig deposition disease presented with acute renal failure, moderate proteinuria, and hematuria. A plasmacytoid lymphocytic infiltrate was identified in bone marrow that produced IgG4 lambda and free lambda light chains. One patient developed an anaplastic plasmacytoma (secreting only lambda light chains) 1 yr after renal biopsy. Renal biopsy in both patients demonstrated a nodular intercapillary glomerulopathy and electron dense granular deposits, associated with a linear pattern of IgG4 heavy chain deposition in vascular, tubular, and glomerular basement membranes (VBM, TBM, and GBM). In one patient this entrapped IgG4 was unassociated with detectable kappa or lambda light chains. In the second patient, lambda light chains (1+) were detected only in the GBM, but IgG4 (4+) was identified in GBM/TBM. Neither circulating (peripheral blood and bone marrow serum) nor cellular free gamma chains were present. We propose the term "pseudo-gamma heavy chain deposition disease" for the process.

Columnar papilloma of the bronchus. Case report and literature review.

Solitary papillomas are rare endobronchial neoplasms that are most commonly lined by a squamous epithelium (i.e., squamous papillomas). Papillomas exhibiting nonsquamous epithelium are even more unusual; only seven solitary papillomas lined by columnar epithelium (i.e., columnar papillomas) have been previously described. The current report presents the eighth patient with a columnar papilloma and demonstrates some features common to solitary papillomas (i.e., central location in the airways, associated atelectasis), but distinctive from squamous papillomas (i.e., absence of malignant potential).

Hypersensitivity pneumonitis versus invasive pulmonary aspergillosis: two cases with unusual pathologic findings and review of the literature.

Two brothers simultaneously exposed to moldy hay, who developed differing forms of Aspergillus-related lung disease, are presented. Patient 1 developed a true case of hypersensitivity lung disease, whereas his brother developed invasive aspergillosis with bronchoalveolar lavage eosinophilia and unusual pathologic features including tissue eosinophilia. The possible overlap between hypersensitivity pneumonitis and invasive aspergillosis in the immunocompetent host is discussed.

Utility of frozen-section evaluation of lymph nodes in the staging of bronchogenic carcinoma at mediastinoscopy and thoracotomy.

We conducted a retrospective analysis of the utility of frozen-section diagnoses in determining lymph node status at mediastinoscopy in 122 consecutive patients with bronchogenic carcinoma. Thirty-five of 122 patients had one or more lymph nodes with frozen-section evaluation positive for metastatic carcinoma. Subsequent nodal sections not in the original frozen-section study revealed metastatic carcinoma in two additional patients. The false-negative rate was 1.6%. Sensitivity was 94.6%. Predictive value of negative frozen-section evaluation results was 97.7%. Because there were no false-positive frozen-section results, specificity and predictive value for positive results of frozen-section evaluation were 100%. The statuses of individual lymph nodes from these 122 patients were also evaluated. Six hundred twenty lymph nodes were sampled from the mediastinum at mediastinoscopy. Frozen-sections in 47 lymph nodes were positive. Subsequent nodal sections not in the original frozen-sections examination revealed metastatic carcinoma in four additional lymph nodes. The false-negative rate was 0.6%. Sensitivity was 92.2%. Predictive value of negative results from frozen-section evaluation was 99.3%. Because there were no false-positive frozen-section results, specificity and predictive value for positive results of frozen-section examination were 100%. We conclude that frozen-section evaluation of lymph nodes at mediastinoscopy reliably indicates lymph node status, thus enabling the physician to decide whether to proceed to thoracotomy. Thus staging of the carcinoma and definitive surgery can be accomplished during a single anesthetic procedure. Combining mediastinoscopy and thoracotomy with frozen-section diagnostic control also reduces both the length and cost of hospitalization.

Wegener's granulomatosis. Immunomicroscopic and ultrastructural study of four cases.

Four cases of Wegener's granulomatosis involving lung are reported in which immunomicroscopy demonstrated that the parenchymal and vascular infiltrates were composed primarily of T cells and monocytes. No IgG, IgA, IgM, or C3 was identified in pulmonary vessels or alveolar septa. Ultrastructural studies failed to demonstrate dense deposits in alveolar septal capillaries or interstitium. These findings indicate that a cellular immune mechanism is active in these forms of pulmonary vasculitis and that immune complex deposition does not play a role.

Amyloidosis and pleural disease.

Pleural involvement with systemic amyloidosis has been reported rarely in the literature. Diagnosis of this entity by percutaneous needle biopsy of the pleura has been described only in two prior case reports. We describe five patients in whom the diagnosis of pleural amyloidosis was established by Cope needle biopsy during evaluation of pleural effusions of indeterminate cause. Three patients presented with a history suggestive of multiorgan disease and a pleural biopsy performed despite a transudative effusion demonstrated amyloid infiltration of the pleura, obviating the need for other organ biopsies. We conclude that in patients with pleural effusions, if history suggests multiorgan involvement and there is suspicion for amyloidosis, then a closed pleural biopsy with special stains for amyloid should be performed even if the effusions are transudative. This may be the diagnostic procedure of choice in such patients.

A prospective comparison of DNA quantitation by image and flow cytometry.

Advances in computer and video technology suggest that image analysis may be practical method of measuring DNA that also allows visual confirmation of cell type. The purpose of this study was to prospectively compare DNA quantitation from 92 solid tumors in which DNA indices had been measured by image analysis of touch preparations (CAS 100) and flow cytometry of cell suspensions (FACScan). For 81 cases, there was excellent correlation between the two methods. For nine cases, however, an aneuploid population, usually near tetraploid, was identified by image but not by flow cytometry. Three cases had aneuploid peaks by flow cytometry that were not identified by image. Although these methods show good correlation, rare populations may be missed by CAS, presumably because of sampling errors in the touch preparation. Aneuploid populations may also be missed by flow cytometry, either because of cell loss during processing or because visual identification by image can increase sensitivity.

Transbronchial needle aspiration for histology specimens.

Fine-gauge (22-G) transbronchial needle aspiration (TBNA) has significantly added to the diagnostic yield of FOB, and in some institutions has become routine in staging bronchogenic carcinoma. Cytologic examination of the specimen obtained by n228G TBNA, however, has several limitations. The mediastinal aspirate can be contaminated by tumor cells from respiratory secretions, giving false positive diagnoses of unresectability. The diagnosis of benign conditions can seldom be made. Using 18-G TBNA, we can obtain specimens for histologic examination from paratracheal, peribronchial, and carinal areas by FOB. Both 18-G and 22-G TBNA were performed in 34 patients with radiographic abnormalities involving mediastinal or hilar areas. Tissue for histologic examination was obtained in 17 patients (50 percent) using 18-G TBNA and was diagnostic in 11 (32 percent), including three patients with benign conditions. The overall diagnostic yeild of 18-G TBNA was 41 percent (14/34 patients), increasing the yield of FOB from 50 percent to 58 percent. There were no false positive results and few minor complications. 18-G TBNA is effective in obtaining tissue for histologic examination and diagnosing benign conditions. In selected cases this technique increases the diagnostic yield of FOB.

Diffuse panbronchiolitis preceding ulcerative colitis.

To expand the clinical spectrum of ulcerative colitis-associated lung disease, we describe a patient with panbronchiolitis associated with ulcerative colitis. In addition to his having a distinctive pulmonary manifestation of this bowel disease, other noteworthy aspects of this patient's course include the onset of pulmonary symptoms several years prior to bowel manifestations and the partial resolution of his pulmonary symptoms following colectomy.

Atheroembolic renal disease: association with renal arterial stenosis.

In elderly patients with generalized atherosclerosis and longstanding hypertension, progressive renal insufficiency should suggest renal artery occlusive disease and/or renal cholesterol embolization. Renal cholesterol embolization is not an absolute contraindication to successful surgical revascularization. Renal cholesterol emboli were identified in biopsy specimens obtained in 24 cases at the Cleveland Clinic from 1978 to 1986, and renal artery stenosis was an associated finding in 19. Clinical manifestations of generalized atherosclerosis were common, including ileofemoral atherosclerosis (18), coronary artery disease (16), carotid occlusive disease (15), and carotid occlusive disease with a history of stroke (8). Evidence of embolic events in other organs was common. Hypertension worsened before biopsy in 21 patients with and without renal artery stenosis. Surgery or angiography definitely or probably contributed to renal failure in 16. Of 12 who underwent surgical revascularization of a renal artery, renal function improved in five, remained stable in five, and worsened in one. Renal function improved in the three patients undergoing dialysis before revascularization, and two were able to discontinue dialysis.