Lipofuscin deposition causes the pigmentation of apocrine hidrocystoma.

Apocrine hidrocystoma (AHC) is a benign cystic lesion arising from apocrine glands and frequently presents as a blue hae with a whitish gloss. It has been reported that the amount of lipofuscin and the degree of its oxidation determines the pigmentation of AHC. However, little is known about the correlation between clinical color and lipofuscin granules. In this study, we histopathologically investigated three cases of AHC and statistically analyzed the quantitative correlation between the clinical color tone and the amount of cytoplasmic lipofuscin deposits. The color tone was quantified as the mean gray value using Image J software. Statistical analysis showed a negative correlative tendency (P = 0.09) between the color tone and the amount of lipofuscin. Our study suggests that the color tone of AHC is associated with the amount of lipofuscin.

Polarizable crystals in apocrine sweat gland tumors: A series of 3 cases.

Polarizable calcium oxalate (CaOx) crystals have been well documented in breast biopsies, generally associated with benign apocrine metaplasia. In contrast, polarizable crystals are only rarely reported in skin adnexal neoplasms. We report 3 different cases of sweat gland tumors with polarizable crystals morphologically suggestive of CaOx: 1 apocrine hidrocystoma and 2 tubular apocrine adenomas. The histologic features were examined in 3 cases. Clinical presentation summary included 2 males and 1 female, ages 53 to 74 years, with lesions located on the left cheek, inferior vertex scalp and the left eyebrow. All 3 cases showed polarizable, geometric, plate-like and fractured, colorless crystals within the lumens of the neoplasm. Of note, these crystals were seen only on the toluidine blue-stained section of Case #1, but were not present on the corresponding permanent section. We hypothesize that polarizable crystals may be present in sweat gland neoplasms more often than previously documented, but that they may often dissolve with routine processing, accounting for their rare visibility. We highlight this rare finding, and suggest that it may be underreported. We only noted this finding in benign apocrine tumors; further investigation would be necessary to determine whether these crystals are also seen in other cutaneous adnexal neoplasms.

Pigmented eyelid cysts revisited: apocrine retention cyst chromhidrosis.

A minority of eyelid hidrocystomas are pigmented containing brown-black contents. Chromhidrosis describes the excretion of colored secretions composed of lipofuscin pigments in apocrine gland-rich anatomic locations. The objective of this study is to evaluate the clinicopathologic features of pigmented eyelid cysts. A case-control study was conducted, examining consecutive pigmented and nonpigmented eyelid hidrocystoma excision specimens. Over a 4-year period, 9 pigmented eyelid hidrocystomas were identified, representing 13% (9/70) of all hidrocystoma excisions. Compared to controls (n = 14), no difference existed for age [mean age 59 (44-78 years) vs. 60 (42-82 years)] or size [mean diameter 2.3 (1-4 mm) vs. 2.7 (1-5 mm)] (pigmented vs. nonpigmented, respectively), but a trend for female, left side, and lower lid predominance for pigmented hidrocystomas existed: 8:1 versus 7:7 F:M; 7:2 versus 7:7 left:right; 8:1 versus 9:5 lower:upper eyelid (pigmented vs. nonpigmented, respectively). Clinically, the pigmented cysts' color varied from dark blue, brown, and to black, and on gross examination, they expressed dark brown to black granular liquid contents. Applying histologic criteria of Jakobiec and Zakka, 8 of 9 and 14 of 14 pigmented and nonpigmented hidrocystomas were of apocrine type. Seven of 9 (78%) pigmented cysts and 6 of 14 (43%) nonpigmented hidrocystomas contained granular eosinophilic cyst contents and/or intracellular cytoplasmic granular pigmented deposits by light microscopy. (The pigmented cyst contents did not survive processing in 2 cases.) By histochemistry (periodic acid Schiff with diastase, Sudan Black, and Fite acid-fast positive staining) and ultraviolet fluorescence, these sediments were determined to be lipofuscin pigments. No hidrocystomas had melanin deposits, and one case had hemosiderin deposits in a scarred cyst wall in addition to cyst lipofuscin pigments. In studies of chromhidrosis, both normal and chromhidrotic apocrine glands contain lipofuscin pigments; the sole difference lies in the amount of lipofuscin granules. Similarly, for eyelid apocrine hidrocystomas, lipofuscin pigments exist in both groups. Presumptively, the amount of lipofuscin and degree of its oxidation distinguish pigmented from nonpigmented apocrine hidrocystomas.

Apocrine hidrocystoma of the lower lip: a case report and literature review.

The hidrocystomas (HCs) are cystic forms of sweat gland resulting from proliferation of the apocrine secretory coil or eccrine duct. Apocrine -HCs are cystic lesions that arise from the apocrine secretory coil, while eccrine -HCs represent retention cysts of the eccrine duct. The commonest site for such lesions is around the eye, and they may also occur on the ears, scalp, chest, shoulders, or feet. However, HCs of the perioral region are uncommon. The differential diagnosis with minor salivary gland cyst or cystic neoplasms often poses a problem in this site. Here we report a rare case of apocrine -HC of the right lower lip for which excisional biopsy of the lesion was performed. Histopathologically, the lesion was a unilocular cyst lined by a double-layered epithelium of the apocrine secretory type. Immunohistochemically, the secretory epithelium was positive for mammaglobin, gross cystic disease fluid protein 15 (GCDFP-15), cytokeratin 7 (CK 7) and CK18, and the myoepithelium was positive for alpha-smooth muscle actin (α-SMA) and weakly positive for S100 protein. Here we present this very rare case of apocrine -HC of the lower lip, and discussed regarding differential diagnosis with minor salivary gland cystic lesion in the lip.

A reappraisal of eyelid eccrine and apocrine hidrocystomas: microanatomic and immunohistochemical studies of 40 lesions.

PURPOSE: To establish reliable criteria for diagnosing eyelid eccrine and apocrine hidrocystomas. DESIGN: Retrospective clinicopathologic and immunohistochemical study. METHODS: Twenty-two specimens of normal portions of eyelids were evaluated to establish the distribution and microanatomy of eccrine and apocrine glands. Immunostaining for cytokeratin 7 (CK7), gross cystic disease fluid protein-15 (GCDFP-15), alpha-smooth muscle actin (α-SMA), epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA) was performed on these tissues and on 40 lesions in 33 patients diagnosed with eccrine or apocrine hidrocystomas by unaided light microscopy. RESULTS: Eccrine glands were not present in the eyelid margins, the lower half of the upper eyelid pretarsal skin, or the pretarsal lower eyelid skin. Apocrine glands were restricted to the eyelid margins and canthi where the cysts were located. GCDFP-15, CK7, and α-SMA immunoreacted with the eccrine secretory coils but not their ducts; apocrine gland secretory spirals also stained positively for these markers throughout their extended courses, but not their short terminal ducts. Positivity was found in 37 of 40 hidrocystomas for α-SMA and 19 for GCDFP-15; lesions tested for CK7 displayed positivity. CONCLUSIONS: Alpha-SMA-, CK7-, and/or GCDFP-15-positive apocrine hidrocystomas were the only type discovered in this series and arose from glandular secretory spirals within the marginal, perimarginal, or canthal skin. Three lesions did not stain for α-SMA, initially suggesting an absent myoepithelium and therefore an eccrine ductal origin; they manifested CK7 positivity, however, another characteristic of the apocrine secretory spiral but not ducts. Our findings disprove the contention that eccrine predominate over apocrine hidrocystomas in the eyelids.

Pigmented apocrine hidrocystoma of the caruncle.

PURPOSE: To describe the clinical and immunopathologic features of the first convincing apocrine hidrocystoma of the caruncle that happened to be pigmented. METHODS: Case report with clinical evaluation, ultrasound biomicroscopy, and paraffin-embedded tissue stained with hematoxylin and eosin, periodic acid-Schiff, and immunohistochemical markers. RESULTS: Ultrasound biomicroscopy identified a cyst occurring in a 56-year-old white woman. Histopathologically, it was lined by an inner eosinophilic columnar epithelium that was gross cystic disease fluid protein-15-positive and evinced apical decapitation secretion and periodic acid-Schiff-positive, diastase-resistant cytoplasmic granules. Fontana- and MART-1-positive melanin granules were demonstrated. There was an outer layer of smooth muscle actin-positive myoepithelial cells. An adjacent apocrine gland was discovered with identical staining characteristics but without melanin granules. CONCLUSIONS: Classical apocrine gland cysts can exceptionally develop in the caruncle. The light dispersion of cytoplasmic melanin found in the lining cells may have contributed to the cyst's clinical pigmentation, which is otherwise generally regarded as the result of the Tyndall effect, wherein blue wavelengths of light reflect from a colloidal solution of lipofuscin and cell debris.

Eccrine mucinous metaplasia associated with an apocrine cystadenoma.

Mucinous metaplasia occurs uncommonly in cutaneous pathology, usually at specialized anatomic locations (genitalia, palms, and soles) and within restricted pathologic contexts (inflammation and trauma). Here, we report a unique case of eccrine mucinous metaplasia associated with an apocrine cystadenoma. A 13-year-old girl had an asymptomatic, 4-mm nodule on the chest. Histopathology demonstrated a typical apocrine cystadenoma in the upper and middle dermis. Adjacent to this lesion was a cluster of coiled eccrine secretory glands, of which the inner layer was almost entirely replaced by benign-appearing cells containing abundant, non-sulfated acid mucopolysaccharides. At 10 months' follow up, there was no recurrence. Our case demonstrates that, very uncommonly, mucinous metaplasia may be associated with a pathogenetically separate, adjacent proliferative adenomatous lesion, in this instance, an apocrine cystadenoma.

Fine-needle aspiration of apocrine hidrocystoma--a potential mimic of papillary neoplasms metastasizing to the skin.

We report the cytologic features of a histologically confirmed apocrine hidrocystoma as seen in fine-needle aspirates. The main cytologic features were the presence of sparse pseudopapillae with mild to moderate atypia in a background of an amorphous navy blue material reminiscent of that seen in aspirates of colloid nodules of the thyroid gland. The pseudopapillae were mistaken for malignant metastatic deposits. It is suggested that the presence of pseudopapillae in aspirates obtained from cutaneous nodules might be a clue for a tentative diagnosis of benign tumors of epidermal adnexae, with the proviso that a primary malignant tumor be ruled out first.

Immunohistochemical analysis of cytokeratin expression in apocrine cystadenoma or hidrocystoma.

Apocrine cystadenoma is a benign sweat gland tumor which consists of various histologic types of epithelium: epithelium with decapitation secretion, pseudostratified epithelium, and flattened epithelium. Immunophenotypes, especially the expression of cytokeratins, in 8 cases of this tumor were examined immunohistochemically, because the nature or differentiation of each epithelium is not well known. The following antibodies were used as primary antibodies: those against involucrin, smooth muscle actin, and human milk fat globulin respectively, and 15 kinds of monoclonal anti-cytokeratin antibodies. Although the staining pattern varied from case to case according to the proportion of each epithelium, these epithelia, except for the flattened epithelium, revealed invariable staining patterns. The staining pattern in the epithelium with decapitation secretion and the pseudostratified epithelium was similar to that in the secretory portion including myoepithelial cells and the junction of the excretory ductal portion with the secretory portion, respectively. However, the flattened epithelium, probably due to intraluminal pressure, showed various staining patterns similar to that in each portion of the apocrine gland. Based on the above observations, we confirmed that apocrine cystadenoma was a complex tumor differentiating into each portion of the apocrine gland, i.e. the dermal duct, the junction of the excretory ductal portion with the secretory portion, and the secretory portion.

Immunohistochemical analysis of cytokeratin expression in multiple eccrine hidrocystoma.

The histologic diagnosis as eccrine hidrocystoma may contain some other cysts which do not originate from the eccrine sweat glands. Some authors have suggested that true eccrine hidrocystoma does not exist. However, multiple eccrine hidrocystoma (Robinson type) is a distinct clinical entity which is characterized by multiple translucent papules around the eyelids which appear in warm weather. Cytokeratin expression in 8 cases of multiple type of unequivocal eccrine hidrocystoma was analyzed immunohistochemically. Immunoreactivities in our cases were similar to those of eccrine dermal ducts. Therefore, we confirmed that these tumors were derived from the eccrine dermal duct, not from the other appendages, and that true eccrine hidrocystoma exists.

Multiple hidrocystomas.

Apocrine hidrocystoma is a cyst from the secretory portion of the apocrine sweat gland and tends to occur as a solitary facial lesion. We report a 66-year-old woman with multiple, cystic lesions on her face. Histopathology revealed cystic spaces lined by a row of secretory cells showing decapitation secretion. We emphasize the multiple character of the case and discuss its distinction from so-called eccrine hidrocystomas.