Fine-Needle Aspiration Cytology of Pilomatrixoma: A Case Report Ritu Bhalotra, M.D., a n d Gita J a y a r a m ,
M.D.
The cytological appearance of breast lesions has been wellstudied. However. skin lesions occurrirg as breast nodules have less often been studied by fine-needle aspiration. In addition, skin tumors occurring over the breast may be clinically mistaken f o r breast carcinoma owing to their fixity to the skin. This article presents one such case and describes its cytologic appearance. Diagn Cytopathol 1990;6:280-283. Key Words: Pilomatrixoma; FNAC
The cytologic appearance of breast lesions has been wellstudied.'-4 Similarly, the cytological appearance of various malignant skin lesions has been described and documented.' However, benign lesions that present as skin or subcutaneous nodules have been less well-studied by fine-needle aspiration (FNA) cytology. For example, the histologic features of pilomatrixoma are well but the cytologic features have been described less frequently.8-'0 This article presents a case of pilomai rixoma and discusses its cytologic appearance.
Case Report A 30-yr-old male was referred to the cytopatholclgist for FNA of a left breast lesion that had been diagnosed clinically as breast carcinoma. The patient had been healthy until 3 mo earlier when he noticed a nodular mass in his left breast, which gradually increased in size. He gave no history of trauma, pain, or nipple discharge. On examination, the patient was a well-built, young man with a 3 x 4 cm, firm, nontender, nodular, reddishpink mass above the areola of the left breast. The nodule was fixed to the skin but free from the deeper structures. General physical and systemic examinations shclwed no obvious abnormality. FNA was performed using a 23gauge needle attached to a 20-ml disposable syringe
Received February 9, 1989. Accepted June 10, 1989. From the Department of Pathology, Maulana Azad Medical College, New Delhi, India. Address reprint requests to Ritu Bhalotra, M.D., 206, Shiekh Sarai, (RPS) Phase 1, New Delhi, 110017, India.
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mounted on a handle. Smears were air-dried, fixed in methanol, and stained with May-Grunwald-Giemsa (MGG). Smears showed clumps of anucleate ovoid to polygonal cells that stained deep blue with MGG. Also seen were clustered and scattered large mononuclear cells with round to ovoid vesicular nuclei and a moderate amount of pale blue cytoplasm with ill-defined cell margins (Figs. 1 and 2). Many of these cells showed cytoplasmic vacuolations. Some clusters showed central anucleate cells and peripheral mononucleate cells (Fig. 3). Multinucleate giant cells were present in close proximity to the mononucleate cells (Fig. 3). Giant cells mainly showed four or five nuclei, but occasional large cells with 30-40 nuclei (Fig. 4) were also seen. The nuclei in the giant cells resembled the nuclei of the mononucleate cells. The clumps of anucleate cells were very thick, so the morphology of the individual cells in these clumps could not be clearly observed. Since the cytologic picture was inconclusive, a repeat FNA was performed. This mainly showed mononucleate cells and giant cells. A descriptive cytologic report was given, ruling out malignancy and suggesting the possibility of a giant-cell lesion. Excision and histopathologic examination were advised.
Histopathology The nodule grossly measured 3 x 2.5 cm and was firm and grayish-white on cut section. Sections showed numerous rounded to ovoid islands of eosinophilic anucleate c e h , surrounded by an intense giant-cell reaction (Fig. 5). Interspersed among these giant cells were many mononucleate cells that resembled macrophages but showed no phagocytic activity (Fig. 6). Occasional clusters of basophilic cells (Fig. 7) were seen around the islands of eosinophilic (shadow) cells, but the majority of nucleated cells were giant cells or mononucleate cells. Most of the mononuclear cells showed prominent nucleoli, and their nuclei resembled the giant-cell nuclei (Fig. 8). Many of the shadow cells showed central keratinization, and deeply 0
1990 WILEY-LISS, INC.
PILOMATRIXOMA
Fig. 1. Seen are mononuclear cells and a few giant cells (MGG, x 300).
basophilic deposits of calcium could be seen replacing some of the shadow cells. A histological diagnosis of pilomatrixoma was made.
Discussion Neoplasms affecting the skin of the breast are rare,” and pilomatrixoma usually occurs over the face, neck, or arms. Forbis and Helwig’ found only a 3% incidence of these tumors on the chest and back, while Ilie” could not find a single case occurring over the breast. A skin tumor that does occur on the breast can be clinically mistaken for a carcinoma, especially because the skin cannot be moved over the mass. A pilomatrixoma in particular may be mistaken for a breast nodule; it frequently manifests as a firm, deep-seated nodule that is covered by normal skin, and it is usually located in the lower dermis, extending
Fig. 2. Smear showing clumped anucleate cells in the center and dissociated cells at the periphery (MGG, x350).
Fig. 3. Mononucleate cells and multinucleate cells are seen around a central conglomerate of anucleate cells (MGG, x 250).
into the subcutaneous fat.I2 The case discussed here was clinically mistaken for a breast carcinoma. Although FNA could not provide a conclusive diagnosis, it was useful in ruling out malignancy. The resemblance of the nuclei of mononucleate cells to the nuclei of giant cells (an appearance simulating giantcell tumor)I3 was seen not only in the cytologic smears (Figs. 1 and 3) but also in the histologic sections (Figs. 6 and 8). In the past, pilomatrixomas have been mistaken histologically for giant-cell tumors, teratomas, and desmoids.’ In our case, the paucity of basophilic cells and the presence of large numbers of giant cells and mononuclear cells further increased the cytodiagnostic problem. The ghost cells were initially overlooked as they were present
Fig. 4. Multinucleate giant cells in pilomatrixoma (MGG, x 500). Diagnostic Cytopathology. Vol6. No 4
28 1
BHALOTRA A N D JAYARAM
Fig. 5. Eosinophilic masses of ghost cells surrounded by mononucleate and giant cells (H&E, x 160).
Fig. 7. A cluster of basaloid cells around an island of eosinophilic cells (H&E, x250).
in thick clumps (Fig. 2 ) which interfered with examining them. On review of cytologic smears, however, a few ghost cells could be made out in the thinner portions of the smears (Fig. 2). In spite of the superficial resemblance of the cytologic picture to that of giant-cell tumor, the clinical appearance of the lesion ruled out this possibility as the lesion was quite clearly located in the skin and subcutaneous tissue. A cytologically descriptive report was given advising histological study, which enabled correct characterization of the lesion. Woyke et a1.,8 in a retrospective study of six cases of pilomatrixoma, were the first to describe its cytologic features. They found many tightly clustered cells and
naked nuclei, the latter leading to a false-positive cytologic diagnosis of malignancy in four cases; unlike in our case, there was a paucity of giant cells and anucleate squames in these aspirates. The remaining two cases received equivocal cytodiagnoses. Reviewing the cytology of pilomatrixoma, Linsk and Franzen' described dense masses of basal cells with poor definition, more readily defined basal cells, occasional partially necrotic masses of cells, and some pink material in the background. Recently, Solanki et al." correctly identified three cases of pilomatrixoma. They observed anucleate squames, basaloid cells, and occasional nucleated squames in a background of chronic inflammatory cells, calcific mate-
Fig. 6. Proliferating mononucleate cells and some multinucleated giant cells (H&E, x400).
Fig. 8. Mononucleate cells and giant cells showing prominent nucleoli (H&E, x400).
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PILOMATRIXOMA
rial, and a few giant cells and fibroblasts. They pointed out that, with time, the number of basaloid cells would be expected to decrease along with a proportionate increase in the shadow cells. (Our case was probably an old calcifying epithelioma containing very few basaloid cells.) This development could lead to a differential diagnostic problem with epidermal inclusion cyst.
References 1. Vilaplana EV, Jimenez Ayala M. The diagnosis of breast lesions. Acta Cytol 1975;19:519-26. 2. Frable WJ. Needle aspiration of the breast. Cancer 1984;53:671-6. 3. Linsk J, Kreuzer G, Zajicek J. Cytologic diagnosis of mammary tumors from aspiration biopsy smears: studies on 210 fibroadenomas and 210 cases of benign dysplasia. Acta Cytol 1972;16:130-8. 4. Mouriquand J, Pasquier D. Fine needle aspiration of breast carcinoma:a preliminary cytoprognostic study. Acta Cytol 1980;24:153-9.
5. Andrade R, Gumport SL, Popkin GL, Rees TD. Cancer of the skin: biology, diagnosis and management. Philadelphia: Saunders, 1976. 6. Malherbe A, Chenantais J. Note sur l’epitheliome calcifie des glandes sebacees. Prog Med 1880;8:826-8. 7. Forbis JR, Helwig EG. Pilomatrixoma (calcifying epitheliorna). Arch Dermatot 1971;83:606-17. 8. Woyke S, Olszewski W, Eichelkraut A. Pilomatrixoma: a pitfall in aspiration cytology of skin tumors. Acta Cytol 1982;26:189. 9. Linsk JA, Franzen S. Clinical aspiration cytology. Philadelphia: Lippincott, 1983:292. 10. Solanki P, Ramzy JR, Durr N, Henkes D. Pilomatrixoma: cytologic features with differential diagnostic considerations. Arch Pathol Lab Med 1987;111:294-97. 11. Ilie B. Neoplasms in skin and subcutaneous tissue over the breast: case reports and review of literature. J Surg Oncol 1986;31:191-8. 12. Lever WF. Histopathology of the skin. 6th ed. Philadelphia: Lippincott, 1983:530-2. 13. Hajdu SI. Pathology of soft tissue tumors. Philadelphia: Lea and Febiger, 1979:104.
Diagnostic Cytopathology,Vol6, No 4
283
M.D.
The cytological appearance of breast lesions has been wellstudied. However. skin lesions occurrirg as breast nodules have less often been studied by fine-needle aspiration. In addition, skin tumors occurring over the breast may be clinically mistaken f o r breast carcinoma owing to their fixity to the skin. This article presents one such case and describes its cytologic appearance. Diagn Cytopathol 1990;6:280-283. Key Words: Pilomatrixoma; FNAC
The cytologic appearance of breast lesions has been wellstudied.'-4 Similarly, the cytological appearance of various malignant skin lesions has been described and documented.' However, benign lesions that present as skin or subcutaneous nodules have been less well-studied by fine-needle aspiration (FNA) cytology. For example, the histologic features of pilomatrixoma are well but the cytologic features have been described less frequently.8-'0 This article presents a case of pilomai rixoma and discusses its cytologic appearance.
Case Report A 30-yr-old male was referred to the cytopatholclgist for FNA of a left breast lesion that had been diagnosed clinically as breast carcinoma. The patient had been healthy until 3 mo earlier when he noticed a nodular mass in his left breast, which gradually increased in size. He gave no history of trauma, pain, or nipple discharge. On examination, the patient was a well-built, young man with a 3 x 4 cm, firm, nontender, nodular, reddishpink mass above the areola of the left breast. The nodule was fixed to the skin but free from the deeper structures. General physical and systemic examinations shclwed no obvious abnormality. FNA was performed using a 23gauge needle attached to a 20-ml disposable syringe
Received February 9, 1989. Accepted June 10, 1989. From the Department of Pathology, Maulana Azad Medical College, New Delhi, India. Address reprint requests to Ritu Bhalotra, M.D., 206, Shiekh Sarai, (RPS) Phase 1, New Delhi, 110017, India.
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Diagnostic Cytopathology, Val 6, No 4
mounted on a handle. Smears were air-dried, fixed in methanol, and stained with May-Grunwald-Giemsa (MGG). Smears showed clumps of anucleate ovoid to polygonal cells that stained deep blue with MGG. Also seen were clustered and scattered large mononuclear cells with round to ovoid vesicular nuclei and a moderate amount of pale blue cytoplasm with ill-defined cell margins (Figs. 1 and 2). Many of these cells showed cytoplasmic vacuolations. Some clusters showed central anucleate cells and peripheral mononucleate cells (Fig. 3). Multinucleate giant cells were present in close proximity to the mononucleate cells (Fig. 3). Giant cells mainly showed four or five nuclei, but occasional large cells with 30-40 nuclei (Fig. 4) were also seen. The nuclei in the giant cells resembled the nuclei of the mononucleate cells. The clumps of anucleate cells were very thick, so the morphology of the individual cells in these clumps could not be clearly observed. Since the cytologic picture was inconclusive, a repeat FNA was performed. This mainly showed mononucleate cells and giant cells. A descriptive cytologic report was given, ruling out malignancy and suggesting the possibility of a giant-cell lesion. Excision and histopathologic examination were advised.
Histopathology The nodule grossly measured 3 x 2.5 cm and was firm and grayish-white on cut section. Sections showed numerous rounded to ovoid islands of eosinophilic anucleate c e h , surrounded by an intense giant-cell reaction (Fig. 5). Interspersed among these giant cells were many mononucleate cells that resembled macrophages but showed no phagocytic activity (Fig. 6). Occasional clusters of basophilic cells (Fig. 7) were seen around the islands of eosinophilic (shadow) cells, but the majority of nucleated cells were giant cells or mononucleate cells. Most of the mononuclear cells showed prominent nucleoli, and their nuclei resembled the giant-cell nuclei (Fig. 8). Many of the shadow cells showed central keratinization, and deeply 0
1990 WILEY-LISS, INC.
PILOMATRIXOMA
Fig. 1. Seen are mononuclear cells and a few giant cells (MGG, x 300).
basophilic deposits of calcium could be seen replacing some of the shadow cells. A histological diagnosis of pilomatrixoma was made.
Discussion Neoplasms affecting the skin of the breast are rare,” and pilomatrixoma usually occurs over the face, neck, or arms. Forbis and Helwig’ found only a 3% incidence of these tumors on the chest and back, while Ilie” could not find a single case occurring over the breast. A skin tumor that does occur on the breast can be clinically mistaken for a carcinoma, especially because the skin cannot be moved over the mass. A pilomatrixoma in particular may be mistaken for a breast nodule; it frequently manifests as a firm, deep-seated nodule that is covered by normal skin, and it is usually located in the lower dermis, extending
Fig. 2. Smear showing clumped anucleate cells in the center and dissociated cells at the periphery (MGG, x350).
Fig. 3. Mononucleate cells and multinucleate cells are seen around a central conglomerate of anucleate cells (MGG, x 250).
into the subcutaneous fat.I2 The case discussed here was clinically mistaken for a breast carcinoma. Although FNA could not provide a conclusive diagnosis, it was useful in ruling out malignancy. The resemblance of the nuclei of mononucleate cells to the nuclei of giant cells (an appearance simulating giantcell tumor)I3 was seen not only in the cytologic smears (Figs. 1 and 3) but also in the histologic sections (Figs. 6 and 8). In the past, pilomatrixomas have been mistaken histologically for giant-cell tumors, teratomas, and desmoids.’ In our case, the paucity of basophilic cells and the presence of large numbers of giant cells and mononuclear cells further increased the cytodiagnostic problem. The ghost cells were initially overlooked as they were present
Fig. 4. Multinucleate giant cells in pilomatrixoma (MGG, x 500). Diagnostic Cytopathology. Vol6. No 4
28 1
BHALOTRA A N D JAYARAM
Fig. 5. Eosinophilic masses of ghost cells surrounded by mononucleate and giant cells (H&E, x 160).
Fig. 7. A cluster of basaloid cells around an island of eosinophilic cells (H&E, x250).
in thick clumps (Fig. 2 ) which interfered with examining them. On review of cytologic smears, however, a few ghost cells could be made out in the thinner portions of the smears (Fig. 2). In spite of the superficial resemblance of the cytologic picture to that of giant-cell tumor, the clinical appearance of the lesion ruled out this possibility as the lesion was quite clearly located in the skin and subcutaneous tissue. A cytologically descriptive report was given advising histological study, which enabled correct characterization of the lesion. Woyke et a1.,8 in a retrospective study of six cases of pilomatrixoma, were the first to describe its cytologic features. They found many tightly clustered cells and
naked nuclei, the latter leading to a false-positive cytologic diagnosis of malignancy in four cases; unlike in our case, there was a paucity of giant cells and anucleate squames in these aspirates. The remaining two cases received equivocal cytodiagnoses. Reviewing the cytology of pilomatrixoma, Linsk and Franzen' described dense masses of basal cells with poor definition, more readily defined basal cells, occasional partially necrotic masses of cells, and some pink material in the background. Recently, Solanki et al." correctly identified three cases of pilomatrixoma. They observed anucleate squames, basaloid cells, and occasional nucleated squames in a background of chronic inflammatory cells, calcific mate-
Fig. 6. Proliferating mononucleate cells and some multinucleated giant cells (H&E, x400).
Fig. 8. Mononucleate cells and giant cells showing prominent nucleoli (H&E, x400).
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Diagnostic Cytopathology,Vol6, No 4
PILOMATRIXOMA
rial, and a few giant cells and fibroblasts. They pointed out that, with time, the number of basaloid cells would be expected to decrease along with a proportionate increase in the shadow cells. (Our case was probably an old calcifying epithelioma containing very few basaloid cells.) This development could lead to a differential diagnostic problem with epidermal inclusion cyst.
References 1. Vilaplana EV, Jimenez Ayala M. The diagnosis of breast lesions. Acta Cytol 1975;19:519-26. 2. Frable WJ. Needle aspiration of the breast. Cancer 1984;53:671-6. 3. Linsk J, Kreuzer G, Zajicek J. Cytologic diagnosis of mammary tumors from aspiration biopsy smears: studies on 210 fibroadenomas and 210 cases of benign dysplasia. Acta Cytol 1972;16:130-8. 4. Mouriquand J, Pasquier D. Fine needle aspiration of breast carcinoma:a preliminary cytoprognostic study. Acta Cytol 1980;24:153-9.
5. Andrade R, Gumport SL, Popkin GL, Rees TD. Cancer of the skin: biology, diagnosis and management. Philadelphia: Saunders, 1976. 6. Malherbe A, Chenantais J. Note sur l’epitheliome calcifie des glandes sebacees. Prog Med 1880;8:826-8. 7. Forbis JR, Helwig EG. Pilomatrixoma (calcifying epitheliorna). Arch Dermatot 1971;83:606-17. 8. Woyke S, Olszewski W, Eichelkraut A. Pilomatrixoma: a pitfall in aspiration cytology of skin tumors. Acta Cytol 1982;26:189. 9. Linsk JA, Franzen S. Clinical aspiration cytology. Philadelphia: Lippincott, 1983:292. 10. Solanki P, Ramzy JR, Durr N, Henkes D. Pilomatrixoma: cytologic features with differential diagnostic considerations. Arch Pathol Lab Med 1987;111:294-97. 11. Ilie B. Neoplasms in skin and subcutaneous tissue over the breast: case reports and review of literature. J Surg Oncol 1986;31:191-8. 12. Lever WF. Histopathology of the skin. 6th ed. Philadelphia: Lippincott, 1983:530-2. 13. Hajdu SI. Pathology of soft tissue tumors. Philadelphia: Lea and Febiger, 1979:104.
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