CED
CPD • Clinicopathological case
Clinical and Experimental Dermatology
An asymptomatic nodule on the forearm € r1 € ngo I. Oguz Topal,1 Y. Topal,2 D. Sakiz3 and S. Gu 1 Department of Dermatology, Okmeydani Research and Training Hospital – Dermatology, Istanbul, Turkey; 2Department of General Surgery, Taksim Research and Training Hospital, Istanbul, Turkey; and 3Department of Pathology, Bakirkoy Dr Sadi Konuk Research and Training Hospital, Istanbul, Turkey
doi: 10.1111/ced.12376
Clinical findings A 53-year-old woman presented with a solitary lesion on her left forearm, which had first appeared approximately 20 years earlier and had gradually increased in size. Physical examination (Fig. 1) revealed a firm, reddish-brown, dome-shaped nodule, 30 9 20 mm in diameter. In addition, there were yellow-brown, circular crusts of around 1 mm in size over the lesion, along with a bleeding ulcerative area.
Histopathological findings On histological examination of a skin biopsy specimen, hyperkeratosis, light acanthosis and focal basaloid cell proliferation were seen in the epidermis. In the dermis, there were cystic dilated and branching tubular structures with papillary projections into the lumen, surrounded by a fibrous stroma. These ducts were surrounded by two layers of epithelial cells. The ductal cells were primarily cuboidal, but some were columnar and/or flattened. The cuboidal cells of the inner layer of the tubular structures showed decapitation secretion (Fig. 2a,b) and were positive for epithelial membrane antigen (EMA) and gross cystic disease fluid protein (GCDFP)-15 (Fig. 2c,d).
Figure 1 A reddish-brown, dome-shaped, nontender nodule,
30 9 20 mm in size, on the patient’s forearm.
What is your diagnosis?
Correspondence: Dr Ilteris Oguz Topal, Department of Dermatology, Batman State Hospital, Batman 72070, Turkey E-mail: [email protected] Conflict of interest: the authors declare that they have no conflicts of interest. Accepted for publication 1 February 2014
760
Clinical and Experimental Dermatology (2014) 39, pp760–762
ª 2014 British Association of Dermatologists
D CP Clinicopathological case
(a)
(b)
(c)
(d)
Figure 2 (a) Irregularly branched structures lined by two or more layers of epithelial cells embedded in the fibroblastic stroma; (b) the
cuboidal cells of the tubular structures showed decapitation secretion, and cellular fragments and eosinophilic debris were visible in the tubular structure. Haematoxylin and eosin, original magnification (a) 9 100; (b)9 300. (c) Immunohistochemical staining for epithelial membrane antigen was positive (original magnification (a) 9 200). (d) Immunohistochemically, numerous cells consisting of the tubular structures stained positive for gross cystic disease fluid protein-15 (original magnification 9 100).
Diagnosis Tubular apocrine adenoma (TAA).
Discussion TAA is an uncommon sweat gland neoplasm that occurs primarily on the scalp, nose, eyelids, legs, back and anogenital region.1–3 TAA typically presents as a reddish-brown papulonodular lesion. Histologically, the benign tumours are composed of dilated duct-like structures of intraluminal papillary projections that vary in size. The ducts are lined by two or more layers of cells. The lumina contains eosinophilic amorphous material. The fibrous stroma around the lesion is well separated from the surrounding dermis. The tumour cells give a positive reaction to carcinoembryonic antigen, S-100 protein, EMA and GCDFP-15.4 The differential diagnosis in cases with this presentation includes other cutaneous neoplasms with
ª 2014 British Association of Dermatologists
intraductal papillary proliferation, including apocrine hidrocystoma, apocrine cystadenoma, apocrine gland carcinoma and especially, papillary eccrine adenoma (PEA). PEA is a benign neoplasm of sweat gland origin. Histologically, PEA tumours are composed of a well-circumscribed dermal mass formed by ducts of varying sizes surrounded by a fibrous stroma.5 There are no definitive histological criteria for differentiating PEA from TAA. Based on the known histological similarities between TAA and PEA, it has been proposed that the terms ‘tubulopapillary hidradenoma’ or ‘papillary tubular adenoma’ be used. Although some researchers consider TAA and PEA to be the same condition, others think that TAA is the apocrine counterpart of PEA. TAA has fewer papillary projections, and its papillae are usually shorter than those associated with PEA. In addition, the luminal cells of the papillae have many areas of decapitation secretion. Compared with PEA, TAA has more connections with the epidermis, and thus may
Clinical and Experimental Dermatology (2014) 39, pp760–762
761
Clinicopathological case
contain a dense infiltration of plasma cells. CEA and EMA are not suitable for differentiating PEA from TAA; however, GCDFP-15 may be useful, as it will yield a positive reaction for TAA, but it is not specific for apocrine differentiation. We diagnosed our patient with TAA based on the presence of decapitation secretion and of immunoreactivity to GCDFP-15, a characteristic marker of apocrine epithelium.6 Complete surgical excision is the recommended treatment for TAA. The histopathological features are benign in nature; however, squamous cell differentiation with keratin production has been reported. Consequently, differentiation of TAA from apocrine carcinomas is critically important. Histological features suggestive of malignancy include atypical mitoses, pleomorphism and necrosis. We did not find any cellular atypia or mitoses in our patient’s tissue.5,6 In conclusion, rare skin tumours, such as TAA, should be considered in the differential diagnosis of tumoral lesions of many years’ duration. Clinicians should be aware that such tumours may be located on nonapocrine areas and that they may differ in clinical appearance, thus appropriate histopathological examination is required.
References 1 Landry M, Winkelmann RK. An unusual tubular apocrine adenoma. Arch Derm 1972; 105: 869–79. 2 Ross I, Shwayder T. Tubular apocrine adenoma: presentation in the vaginal introitus of an eight-year-old. Pediatr Dermatol 2010; 27: 200–1. 3 Mitsuishi T, Kawana S. Tubular apocrine adenoma of the nose. Eur J Dermatol 2011; 21: 132. 4 Makuruna CN. Papillary tubular adenoma of the skin. J Dermatol 1993; 20: 311–13. 5 Ichikawa E, Okabe S, Umebayashi Y et al. Papillary eccrine adenoma: immunohistochemical studies of keratin expression. J Cutan Pathol 1997; 24: 564–70. 6 Ishiko A, Shimizu H, Inamoto N, Nakmura K. Is tubular apocrine adenoma a distinct clinical entity? Am J Dermatopathol 1993; 15: 482–7.
Learning points
• •
TAA is an uncommon sweat gland neoplasm. The most common site is the scalp, but lesions may also be located on nonapocrine areas. • The differential diagnosis of TAA includes other cutaneous neoplasms with intraductal papillary proliferation. • GCDFP-15 positivity might be diagnostically useful, and histopathological examination is important for accurate diagnosis.
762
Clinical and Experimental Dermatology (2014) 39, pp760–762
ª 2014 British Association of Dermatologists
CPD • Clinicopathological case
Clinical and Experimental Dermatology
An asymptomatic nodule on the forearm € r1 € ngo I. Oguz Topal,1 Y. Topal,2 D. Sakiz3 and S. Gu 1 Department of Dermatology, Okmeydani Research and Training Hospital – Dermatology, Istanbul, Turkey; 2Department of General Surgery, Taksim Research and Training Hospital, Istanbul, Turkey; and 3Department of Pathology, Bakirkoy Dr Sadi Konuk Research and Training Hospital, Istanbul, Turkey
doi: 10.1111/ced.12376
Clinical findings A 53-year-old woman presented with a solitary lesion on her left forearm, which had first appeared approximately 20 years earlier and had gradually increased in size. Physical examination (Fig. 1) revealed a firm, reddish-brown, dome-shaped nodule, 30 9 20 mm in diameter. In addition, there were yellow-brown, circular crusts of around 1 mm in size over the lesion, along with a bleeding ulcerative area.
Histopathological findings On histological examination of a skin biopsy specimen, hyperkeratosis, light acanthosis and focal basaloid cell proliferation were seen in the epidermis. In the dermis, there were cystic dilated and branching tubular structures with papillary projections into the lumen, surrounded by a fibrous stroma. These ducts were surrounded by two layers of epithelial cells. The ductal cells were primarily cuboidal, but some were columnar and/or flattened. The cuboidal cells of the inner layer of the tubular structures showed decapitation secretion (Fig. 2a,b) and were positive for epithelial membrane antigen (EMA) and gross cystic disease fluid protein (GCDFP)-15 (Fig. 2c,d).
Figure 1 A reddish-brown, dome-shaped, nontender nodule,
30 9 20 mm in size, on the patient’s forearm.
What is your diagnosis?
Correspondence: Dr Ilteris Oguz Topal, Department of Dermatology, Batman State Hospital, Batman 72070, Turkey E-mail: [email protected] Conflict of interest: the authors declare that they have no conflicts of interest. Accepted for publication 1 February 2014
760
Clinical and Experimental Dermatology (2014) 39, pp760–762
ª 2014 British Association of Dermatologists
D CP Clinicopathological case
(a)
(b)
(c)
(d)
Figure 2 (a) Irregularly branched structures lined by two or more layers of epithelial cells embedded in the fibroblastic stroma; (b) the
cuboidal cells of the tubular structures showed decapitation secretion, and cellular fragments and eosinophilic debris were visible in the tubular structure. Haematoxylin and eosin, original magnification (a) 9 100; (b)9 300. (c) Immunohistochemical staining for epithelial membrane antigen was positive (original magnification (a) 9 200). (d) Immunohistochemically, numerous cells consisting of the tubular structures stained positive for gross cystic disease fluid protein-15 (original magnification 9 100).
Diagnosis Tubular apocrine adenoma (TAA).
Discussion TAA is an uncommon sweat gland neoplasm that occurs primarily on the scalp, nose, eyelids, legs, back and anogenital region.1–3 TAA typically presents as a reddish-brown papulonodular lesion. Histologically, the benign tumours are composed of dilated duct-like structures of intraluminal papillary projections that vary in size. The ducts are lined by two or more layers of cells. The lumina contains eosinophilic amorphous material. The fibrous stroma around the lesion is well separated from the surrounding dermis. The tumour cells give a positive reaction to carcinoembryonic antigen, S-100 protein, EMA and GCDFP-15.4 The differential diagnosis in cases with this presentation includes other cutaneous neoplasms with
ª 2014 British Association of Dermatologists
intraductal papillary proliferation, including apocrine hidrocystoma, apocrine cystadenoma, apocrine gland carcinoma and especially, papillary eccrine adenoma (PEA). PEA is a benign neoplasm of sweat gland origin. Histologically, PEA tumours are composed of a well-circumscribed dermal mass formed by ducts of varying sizes surrounded by a fibrous stroma.5 There are no definitive histological criteria for differentiating PEA from TAA. Based on the known histological similarities between TAA and PEA, it has been proposed that the terms ‘tubulopapillary hidradenoma’ or ‘papillary tubular adenoma’ be used. Although some researchers consider TAA and PEA to be the same condition, others think that TAA is the apocrine counterpart of PEA. TAA has fewer papillary projections, and its papillae are usually shorter than those associated with PEA. In addition, the luminal cells of the papillae have many areas of decapitation secretion. Compared with PEA, TAA has more connections with the epidermis, and thus may
Clinical and Experimental Dermatology (2014) 39, pp760–762
761
Clinicopathological case
contain a dense infiltration of plasma cells. CEA and EMA are not suitable for differentiating PEA from TAA; however, GCDFP-15 may be useful, as it will yield a positive reaction for TAA, but it is not specific for apocrine differentiation. We diagnosed our patient with TAA based on the presence of decapitation secretion and of immunoreactivity to GCDFP-15, a characteristic marker of apocrine epithelium.6 Complete surgical excision is the recommended treatment for TAA. The histopathological features are benign in nature; however, squamous cell differentiation with keratin production has been reported. Consequently, differentiation of TAA from apocrine carcinomas is critically important. Histological features suggestive of malignancy include atypical mitoses, pleomorphism and necrosis. We did not find any cellular atypia or mitoses in our patient’s tissue.5,6 In conclusion, rare skin tumours, such as TAA, should be considered in the differential diagnosis of tumoral lesions of many years’ duration. Clinicians should be aware that such tumours may be located on nonapocrine areas and that they may differ in clinical appearance, thus appropriate histopathological examination is required.
References 1 Landry M, Winkelmann RK. An unusual tubular apocrine adenoma. Arch Derm 1972; 105: 869–79. 2 Ross I, Shwayder T. Tubular apocrine adenoma: presentation in the vaginal introitus of an eight-year-old. Pediatr Dermatol 2010; 27: 200–1. 3 Mitsuishi T, Kawana S. Tubular apocrine adenoma of the nose. Eur J Dermatol 2011; 21: 132. 4 Makuruna CN. Papillary tubular adenoma of the skin. J Dermatol 1993; 20: 311–13. 5 Ichikawa E, Okabe S, Umebayashi Y et al. Papillary eccrine adenoma: immunohistochemical studies of keratin expression. J Cutan Pathol 1997; 24: 564–70. 6 Ishiko A, Shimizu H, Inamoto N, Nakmura K. Is tubular apocrine adenoma a distinct clinical entity? Am J Dermatopathol 1993; 15: 482–7.
Learning points
• •
TAA is an uncommon sweat gland neoplasm. The most common site is the scalp, but lesions may also be located on nonapocrine areas. • The differential diagnosis of TAA includes other cutaneous neoplasms with intraductal papillary proliferation. • GCDFP-15 positivity might be diagnostically useful, and histopathological examination is important for accurate diagnosis.
762
Clinical and Experimental Dermatology (2014) 39, pp760–762
ª 2014 British Association of Dermatologists
