Cytomorphology of Adrenocortical Carcinoma and Comparison with Renal Cell Carcinoma
Suash Sharma, M.D., D.N.B., Rajvir Singh, M.A., and Kusum Verma, M.D., M.I.A.C., F.A.M.S.
OBJECTIVE: To review the cytomorphologic features of adrenocortical carcinoma (ACC), correlate them with histology and compare them with the cytomorphologic features of very similar renal cell carcinoma (RCC) on fine needle aspiration (FNA) smears.
STUDY DESIGN: Cytomorphologic features in 7 cases of ACC in FNA smears were analyzed and compared with those in 10 cases of RCC. Five cases of ACC and five of RCC were later confirmed on histopathology. Parameters analyzed pertained mainly to architectural, cytoplasmic and nuclear features.
This study on the FNA cytologic diagnosis of ACC elucidated the prospects for an early, firm diagnosis of the lesion, the subject of tremendous controversy.
RESULTS: The presence of cells in sheets with a central, thin-walled vascular core (endocrine vascular pattern); monomorphic cell popula- tion; eccentric nuclei; focal dramatic anisonucleosis; and focal spindling with crushing was a prominent feature of ACC in contrast to RCC, which showed mainly an aci- nar pattern with only a focal endocrine pattern, well- defined cytoplasmic angles and projections, and cyto- plasmic vacuolations; pleomorphism, if present, was gradual and seen uniformly in all the cells. Univariate analysis using the x2 test showed the presence of en- docrine architecture; focal dramatic anisonucleosis;
crushed spindle fragments; eccentric nuclei; and absence of cytoplasmic vacuolizations as significant differentiat- ing features in favor of ACC (P <. 05).
CONCLUSION: A cytomorphologic comparison of ACC with RCC showed that differentiation is possible by a set of statistically significant features that not only have diagnostic value but, as with crushed spindle frag- ments, also have prognostic significance. (Acta Cytol 1997;41:385-392)
Keywords: carcinoma, adrenal cortical; kidney neoplasms; aspiration bi- opsy.
Adrenal cortical carcino- mas constitute <0.05% of all malignant neoplasms in the human body.3,7,23,24 With the advent of ab- dominal imaging modalities, these are now detect- ed at an early stage,2,21 increasing the need for more accurate diagnosis and prognostication. Hence, at- tempts have been made to review the histopatholo- gy, and in the last decade, three sets of histologic criteria have been formulated for diagnosing these tumors.8,16,25,28
Fine needle aspiration biopsy (FNA), a simple
From the Cytopathology Laboratory, Departments of Pathology and Biostatistics, All India Institute of Medical Sciences, New Delhi, India.
Dr. Sharma is Senior Resident, Department of Pathology.
Mr. Singh is Research Associate, Department of Biostatistics.
Dr. Verma is Professor of Cytopathology, Department of Pathology.
Address reprint requests to: Kusum Verma, M.D., M.I.A.C., F.A.M.S., Department of Pathology, All India Institute of Medical Sciences, New Delhi 110029, India.
Received for publication May 2, 1995.
Accepted for publication August 28, 1995.
0001-5547 /97/4102-0385/$02.00/0 @ The International Academy of Cytology Acta Cytologica
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technique, is often used with or without radiologic guidance to diagnose retroperitoneal masses. The first case of adrenocortical carcinoma (ACC) diag- nosed on FNA was reported by Levin in 1981.12 Since then many isolated case reports and reports of three to four cases have been published.1,10,19,26 No diagnostic criteria are available in the literature for differentiating adrenocortical carcinomas from renal tumors on FNA.
The aim of the study was to review the cytologic features of ACC diagnosed on FNA, correlate them with histology and compare the cytomorphologic features with those of very similar renal cell carci- noma (RCC) on aspirates.
Materials and Methods
In this retrospective study, cytomorphologic fea- tures of seven cases of adrenal carcinomas, from primary as well as metastatic sites, collected from cytopathology files were analyzed. Five of these cases were later confirmed on histopathology, while all the cases had radiologic confirmation. Ten cases of RCC diagnosed on FNA were used for com- parison.
The age range of the patients was 4-50 years. There were six males and one female. Their clinical characteristics and radiologic and histopathologic diagnoses are summarized in Table I.
Needle aspiration was performed via the anterior
| Case no. | Age (yr) | Sex | Duration of symptoms (mo) | Site of FNA | Radiology | Size (cm) | Histopathology | Functional status |
|---|---|---|---|---|---|---|---|---|
| 1 | 37 | M | 6 | Left abd mass | Adrenal mass | 252 122 6 | ACC 1,830 g | Inactive |
| 2 | 30 | F | 8 | Right abd mass | Adrenal mass | 82 12 | ACC | Inactive |
| 3 | 6 | M | 12 | Right abd mass | Adrenal mass | 102 12 | ACC | Cushing's syn- drome |
| 4 | 4 | M | 6 | Left abd mass | Adrenal mass | 152 20 | ACC L.N. 3/6 | Inactive |
| 5 | 50 | M | 1.5 | Right liver mass | Adrenal mass | 72 5 | — | Inactive |
| 6 | 45 | M | 1 | Right epigastric mass | Adrenal mass | — | — | Inactive |
| 7 | 42 | M | 3 | Right abd mass | Adrenal mass | 102 10 | ACC | Inactive |
abd = abdominal.
L.N. = lymph nodes.
| Cytomorphologic features | ACC (7) | RCC (10) | ||
|---|---|---|---|---|
| Type | No. of cases | Type | No. of cases | |
| Architectural features | ||||
| 1. Pattern | ||||
| Endocrine | +++ | 5 | + | 8 |
| Acinar | + | 2 | +++ | 10 |
| 2. Cell arrangement | ||||
| Syncytial | +++ | 5 | + | 3 |
| Monolayers | ++ | 3 | ++ | 8 |
| Single cells | ++ | 4 | + | 4 |
| (MD & PD) | ||||
| 3. Necrosis | + | 4 | + | 1 |
| (PD) | ||||
| 4. Crushed, spindled fragments | + | 4 | 1 | 0 |
| 5. Admixture with normal tissue | + | 1 | 1 | 0 |
| Cytoplasmic features | ||||
| 1. Contour | ||||
| Anisomorphic with rounded ends | + | 7 | + | 10 |
| Polygonal with sharp angles, projections | 1 | 0 | +++ | 10 |
| 2. Vacuolation | 1 | 0 | + | 10 |
| 3. Density | ||||
| Dense | ++ | 7 | + | 5 |
| Foamy | + | 2 | +++ | 10 |
| Granular | 1 | 0 | + | 4 |
| Nuclear features | ||||
| 1. Position | ||||
| Central | 1 | 0 | + | 10 |
| Eccentric | + | 7 | + | 2 |
| 2. Pleomorphism | ||||
| Gradual, uniform | 1 | 0 | + | 4 |
| (MD & PD) | ||||
| Focal, dramatic anisonucleosis | + | 7 | 1 | 0 |
| 3. Nucleoli | ||||
| Single, small | + | 1 | + | 4 |
| Multiple, large | − | 0 | + | 4 |
| (MD & PD) | ||||
| 4. Chromatin | ||||
| Uniform | + | 7 | + | 6 |
| Irregular clumping | 1 | 0 | + | 4 |
| (MD & PD) | ||||
| 5. Prominent chromocenters | + | 4 | + | 4 |
| (MD & PD) | ||||
| 6. Nuclear membrane | ||||
| Regular | + | 7 | + | 6 |
| Irregular | 1 | 0 | + | 4 |
| (MD & PD) | ||||
| 7. Giant cells, bizarre cells | + | 5 | + | 2 |
| + | 1 | + | 2 | |
| 8. Mitosis | + | 6 | + | 10 |
MD = moderately differentiated, PD = poorly differentiated by Linsk’s classification.12,13
approach using a Cameco pistol (Cameco Ltd., Lon- don, U.K.), 10-ml syringe and 23-gauge needle, 3.8 cm long, using the standard technique. A portion of the aspirated specimen was fixed immediately
in 95% ethyl alcohol and stained by the Papanico- laou method. The rest of the specimen was air dried and stained with May-Grünwald-Giemsa (MGG) stain.
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Results
The cytomorphologic features of ACC and RCC are summarized in Table II.
Cytomorphologic Features of ACC
The FNA smears from ACC were cellular and showed cells in sheets as well as singly in a dis- persed pattern. The sheets had a very striking en- docrine vascular pattern, characterized by an inter- connecting, thin-walled, central vascular core forming an organoid contour in places (Figure 1). This was seen as the predominant pattern (5/7 cases).
Individual cells showed dense cytoplasm and ec- centric, small, vesicular nuclei without conspicuous nucleoli. The cells were generally monomorphic. However, characteristically, occasional cells in a fragment showed a sudden, marked increase in size, three to five times larger than neighboring cells, without associated atypia or inclusions. This feature was termed “focal dramatic anisonucleosis” (Figure 2). Only an occasional cell had foamy cyto- plasm.
Another feature was the presence of fragments of tumor cells showing spindling. These cells pos- sessed hyperchromatic nuclei with frayed nuclear
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outlines, superficially suggesting crushing. These were labeled “crushed spindle fragments” (Figure 3). These cells showed focal grouping, a somewhat organoid pattern and a transition with polygonal tumor cells. No admixture with fibroblasts or stro- mal cells was observable.
Mitotic figures were conspicuous in all cases. In addition, giant cells, an admixture with normal adrenal cells (Figure 4) and infiltration of fat and skeletal muscle were also present in occasional cases.
Cytomorphologic Features of RCC
The smears were cellular and showed cells in sheets as well as singly. However, in contrast to ACC, the
predominant architectural pattern was acinar (Fig- ure 5). The endocrine pattern, if at all present, was seen only focally.
Individual cells of RCC, in contrast to those of ACC, had a well-defined, polygonal outline with cytoplasmic angles and projections, usually central- ly placed nuclei (except oncocytes), prominent nu- cleoli and cytoplasmic vacuolations that were most detectable on MGG stain (Figure 6A).
In contrast to ACC, in cases of RCC, pleomor- phism, when present, was seen uniformly through- out the tumor cell population. Hence, the cases of RCC were graded, using Linsk’s classification,12,13 into the following groups:
(a) Well differentiated. Cases 5-10 showed a monomorphic population of small, uniform-sized cells with bland nuclei with a low nuclear/ cytoplasmic ratio and bubbly, vacuolated cyto- plasm.
(b) Moderately differentiated. Cases 2 and 4 showed the beginnings of cell dispersion in a back- ground of monolayered fragments with larger nu- clei and moderate pleomorphism. The nucleoli were generally single per cell and variably sized. Cytoplasmic vacuolation was present. Case 2 showed a significantly large number of oncocytic cells.
(c) Poorly differentiated. Cases 1 and 3 showed largely dispersed cells having large nuclei with moderate to marked pleomorphism and multiple macronucleoli (Figure 6B). Cytoplasmic vacuoliza- tion, though less, was present, even in poorly dif- ferentiated RCC (Figure 7).
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Cytohistopathologic Correlation
Corresponding histopathologic sections of ACC, when available, prominently showed the endocrine architecture of the tumor, with a monomorphic cell population showing eccentric nuclei (Figure 8A). Focal dramatic anisonucleosis was also visible. Spindling corresponded to the neighboring cell population’s dense, fibrous septae traversing the tumor (Figure 8B).
RCCs were histopathologically of the clear cell, nonpapillary variety in four cases, and one case had predominantly oncocytic cells.
Statistical Analysis
Univariate analysis was performed using the x2 test with Yates’s correction factor (P <. 05) to determine the statistically significant differentiating features between RCC and ACC. Predominant endocrine ar- chitecture; focal dramatic anisonucleosis; crushed spindle fragments; eccentric nuclei; and absence of cytoplasmic vacuolizations were significant differ- entiating features in favor of ACC in contrast to RCC.
Discussion
ACC is a rare malignant tumor but poses major problems for diagnosticians. The separation of be- nign from malignant tumors has been extensively worked upon in the last decade, and at least three sets of histologic criteria, with and without clinical
criteria, have been found to be of diagnostic value.8,16,25,28 Some cases remain in which the course of the disease is perhaps the only distin- guishing feature.25 In the present study, the cases detected clearly fit into the malignant category using clinical, radiologic and cytologic criteria, ei- ther alone or in combination.
Positive identification of a tumor as of adrenal origin histogenetically and its histologic differenti- ation from very similar neoplasia, especially RCC, may be a diagnostic dilemma on radiology and his- tology. The problem is evident from the fact that
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ACC was included in the description of tumors of the kidney by Grawitz6 and was differentiated from them only later on histologic grounds.5 The present study addresses mainly the latter problem in detail using fine needle aspiration cytology, a technique being utilized increasingly as a diagnostic modality for early and rapid diagnosis of these cases.
We failed to find any set criteria for the diagnosis of ACC on aspirates in the literature.1,10,12,19,26 No definite architectural pattern has been recognized, and pleomorphism, if noted, has been described as occurring uniformly in all the cells.10,19 Hence, it has been especially difficult to differentiate ACC from tumors like RCC on aspirates.
It is evident from the present study that though all RCCs, including well-differentiated ones, are very similar to ACCs, yet the presence of the char- acteristic endocrine pattern; crushed, spindled frag- ments; focal dramatic anisonucleosis; eccentric nu- clei; and absence of cytoplasmic vacuolations are certainly features that make ACC look distinct from RCC. The endocrine pattern, seen at least focally, and eccentric nuclei (in oncocytic cells) were ob- served in RCCs in the present study as well as oth- ers.14,15 Further, foaminess and slight vacuolation of the cytoplasm have been variably cited in the lit- erature as observed in ACCs.1,10,12 However, focal dramatic anisonucleosis and crushed, spindled fragments were strikingly present exclusively in ACCs in this study.
Cytomegaly and nucleomegaly of adrenocortical cells is seen most commonly diffusely scattered in
children and was first noted by Kampmeier in 1927.9 It is present rarely in adults as scattered cells.13 This enlargement of cells and nuclei was not associated with any features of anaplasia, such as hyperchromatism or irregular clumping of chro- matin. Robinson noted the presence of occasional such cells in adult pigmented adenomas.22 Adeno- matous lesions, consisting predominantly of such large cells, have also been reported.4,17,20 To the best of our knowledge, this is the first study to demonstrate the presence of focal cytomegaly and nucleomegaly in ACC. The cells and nuclei were three to five times larger than the neighboring cells. Also, there was no evidence of degeneration or cy- tomegalic inclusion disease in these cases. The change was termed “focal dramatic anisonucleosis” and was consistently seen in the aspirates as well as corresponding histologic sections. Focal, dramatic anisonucleosis was in complete contrast to the pleo- morphism in RCC: it was uniform, more gradual and associated with increasing nuclear atypia. A similar change has been noted only in multinucleat- ed giant cells by earlier workers.12,26
Crushed, spindled fragments in FNA smears cor- responded to the tumor cells, with adjoining thick, fibrous septae traversing the tumor on histologic sections. These spindle cells showed focal group- ing, a partial organoid pattern and a transition with polygonal tumor cells. They did not have admixed fibroblasts in them. Dense, fibrous septae have been consistently observed in ACC and generally re- garded as a sign of an ominous prognosis. Hough et
al,8 in their classification, gave the second highest numeric value for predicting metastasis to broad, fi- brous bands. Van Slooten et al25 included fibrous bands in regressive changes along with necrosis, hemorrhage and calcification and gave these changes the second highest numeric value for pre- dicting prognosis. Hence, it is imperative that the cytologic counterpart of crushed, spindled frag- ments should have equally sinister significance in both diagnosis and prognostication. Spindling on histologic sections per se has generally been accept- ed by some workers as an indication of malignancy along with distinctly bizarre nuclei and a high mi- totic rate.11,19 Moreover, the presence of spindle cells, especially in the form of vascularized micro- tissue fragments, with or without bizarre tumor cell fragments, is of diagnostic help even in the aspi- rate.8,19,27 The pattern of spindling of tumor cells in the present study was quite similar to that in Figure 27 of Kay’s paper11; he considered it indicative of malignancy.11
To conclude, this study on the FNA cytologic di- agnosis of ACC elucidated the prospects for an early, firm diagnosis of the lesion, the subject of tremendous controversy.
References
1. Cochand-Priollet B, Jacquenod P, Warnet A, Ferrand J, Galian J: Adrenal cortical carcinoma: A case diagnosed by fine needle aspiration cytology. Acta Cytol 1988;32:128-130
2. Copeland PM: The incidentally discovered adrenal mass. Ann Intern Med 1983;98:940-945
3. Didolkar MS, Bescher RA, Elias EG, Moore RH: Natural his- tory of adrenal cortical carcinomas. Cancer 1981;47:2153- 2161
4. Feurstein IM, Tiamson EM: Focal cytomegaly of adult adren- al cortex: A rare variant of black adenoma. Arch Pathol Lab Med 1985;109:198-200
5. Geschickten CF: Supra-renal tumors. Am J Cancer 1935;23: 104-115
6. Grawitz P: Die Entsehung van Nierentumoren aus Neben- niergewebe. Arch Klin Chir 1884;30:824
7. Greenberg PH, Marks C: Adrenal cortical carcinoma: A pre- sentation of 22 cases and a review of literature. Am Surg 1978;44:81-85
8. Hough AJ, Hollifield JW, Page DL, Hartman WH: Prognos- tic factors in adrenal cortical tumors: A mathematical analy- sis of clinical and morphological data. Am J Clin Pathol 1979;72:390-392
9. Kampmeier OF: Giant epithelial cells of the human adrenal
cortex. Anat Rec 1927;37:95-102
10. Katz RL, Patel S, Mackay B, Zornoza J: Fine needle aspiration cytology of the adrenal gland. Acta Cytol 1984;28:269-282
11. Kay S: Hyperplasia and neoplasia of adrenal gland. Pathol Annu 1976;11:103-140
12. Levin NP: Fine needle aspiration and histology of adrenal cortical carcinoma: A case report. Acta Cytol 1981;24:421- 424
13. Liebergott G: Studien zur orthologie und Pathologie der Nebenniren. Beitr Z Pathol Anat 1944;109:93-178
14. Linsk JA, Franzén S: Aspiration cytology of metastatic hy- pernephroma. Acta Cytol 1984;28:250-260
15. Linsk JA, Franzén S: Clinical Aspiration Cytology. Philadel- phia, JB Lippincott, 1983, pp 195-200
16. Medeiros LJ, Weiss LM: New developments in the patholog- ic diagnosis of adrenal cortical carcinomas: A review. Am J Clin Pathol 1992;97:73-83
17. Nakamura Y, Yano H, Nakashima T: False intranuclear in- clusions in adrenal cytomegaly. Arch Pathol Lab Med 1981; 105:358-360
18. Nance KV, McLeod DL, Silverman JF: Fine needle aspiration cytology of spindle cell neoplasms of the adrenal gland. Diagn Cytopathol 1992;8:235-241
19. Nguyen GK: Percutaneous fine needle aspiration biopsy cy- tology of kidney and adrenal. Pathol Annu 1987;22:163-192
20. Oppenheimer EH: Adrenal cytomegaly: Studies by light and electron microscopy. Arch Pathol Lab Med 1970;90:57-64
21. Prinz RA, Brooks MH, Churchill R, Graner JL, Lawrence AM, Paloyan E, Sparagana M: Incidental asymptomatic adrenal masses detected by computer tomographic scan- ning: Is operation required? J Am Med Assoc 1982;248: 701-704
22. Robinson MJ, Pardo V, Rywlin AM: Pigmented nodules (Black Adenomas) of adrenal: An autopsy study of inci- dence, morphology and function. Hum Pathol 1972;3:317- 325
23. Samaan NA, Hickey RC: Adrenal cortical carcinoma. Semin Oncol 1987;14:292-296
24. Third National Cancer Survey: Incidence Data. Bethesda, Maryland, U.S.A., National Cancer Institute, 1975, pp 75-787
25. Van Slooten H, Schabeng A, Smeenk D, Mollenaar AJ: Mor- phologic characteristics of benign and malignant adrenocor- tical tumors. Cancer 1985;55:766-773
26. Varma S, Amy RW: Adrenal cortical carcinoma metastatic to the lung: Report of a case diagnosed by fine needle aspira- tion biopsy. Acta Cytol 1990;34:104-105
27. Wadih GE, Nance KV, Silverman JF: Fine needle aspiration cytology of adrenal gland: Fifty biopsies in 48 patients. Arch Pathol Lab Med 1992;116:841-846
28. Weiss LM: Comparative histologic study of 43 metastasizing and non-metastasizing adrenocortical tumors. Am J Surg Pathol 1984;8:163-169