Ocular adnexal oncocytoma: a case series and clinicopathologic review of the literature

Oncocytic Metaplasia in Melanocytic Tumors

Oncocytic metaplasia represents a histopathologic feature that can be observed in normal tissue such as salivary and lacrimal glands but may also constitute a degenerative metaplastic process as a result of repeated oxidative damage during cellular aging. Although cutaneous oncocytic metaplasia has been considered rare, the finding was seen in over one-third of melanocytic nevi prospectively evaluated, in one study. This case series reports on a small series of oncocytic melanocytic tumors, with the aim of describing this phenomenon in varied contexts and also describing the use of a mitochondrial antigen immunostain, which has not been previously reported.

Unusual Histopathological Patterns in Melanocytic Nevi With Some Previously Undescribed Patterns

Melanocytic nevi are one of the most common diagnoses in the daily practice of any dermatopathologist. Although in the vast majority of cases the final diagnosis is not difficult, there are certain rare and unusual morphologic variations that can elicit some diagnostic problems. Although some of these variations can be considered as mere morphologic oddities, others might lead to a differential diagnosis with melanoma, or with other tumors, including epithelial or neural tumors. In the current report, we review many of these morphologic variations and discuss the main differential diagnosis, when appropriate.

Phakomatous choristoma in a 10-week-old boy: a case report and review of the literature

Phakomatous choristoma (PC) is a rare benign congenital lesion of lenticular anlage. It presents in young patients as a firm subcutaneous mass in the medial eyelid or orbit and may raise clinical concern for neoplasms such as rhabdomyosarcoma, but its histopathology is distinct, consisting of dense collagenous stroma and eosinophilic cuboidal epithelial cells forming nests, tubules, cords, or pseudoglands. We present a case of PC in a 10-week-old boy to illustrate the unique clinical, histopathologic, and immunophenotypic features of this condition and to reaffirm that familiarity with this rare entity aids accurate diagnosis.

Atypical presentation of a pigmented oncocytoma of the caruncle: a case report

We report an unusual case of a pigmented oncocytoma of the caruncle. The lesion presented the following atypical features: a well-circumscribed, partially pigmented, and lobulated mass that macroscopically resembled a caruncular nevus. However, an excision biopsy revealed an oncocytoma instead. Thus, although nevi are the most common lesions found in the caruncle, oncocytoma should also be considered in the differential diagnosis of a pigmented caruncular mass, especially in elderly female patients.

Oncocytic lesions (oncocytoma) of the ocular adnexa: report of 15 cases and review of literature

PURPOSE

To describe the clinical, imaging, and pathology features of oncocytic lesions in the ocular adnexa.

METHODS

Retrospective, noncomparative, interventional case series.

RESULTS

Fifteen oncocytic neoplasms (n = 15 patients) were classified as oncocytoma in 14 (93%) and oncocytic hyperplasia in 1 (7%). The mean patient age was 66 years (median = 66, range = 44-82), and 9 (60%) were male. The tumor involved the caruncle (n = 13, 86%), bulbar conjunctiva (n = 1, 7%), and plica semilunaris (n = 1, 7%). All cases were unifocal and most often presented as a painless mass (n = 12, 80%), evolving over a median 6 months (mean = 12, range = 1-48 months). The mean tumor base was 4.1 mm (median = 4.0, range = 1-10), and the tumor was well-circumscribed (n = 14), dark blue (n = 7), and cystic (n = 10). Ultrasound biomicroscopy and anterior segment optical coherence tomography disclosed mixed solid and cystic components. Complete surgical excision was curative without recurrence after a mean follow up of 39 months. Histopathology disclosed columnar cells with copious quantities of intensely eosinophilic cytoplasm in the lining epithelium (oncocytic hyperplasia) and in some cases with cystadenomatous proliferation (oncocytoma).

CONCLUSION

Oncocytic lesions of the ocular adnexae are typically well-circumscribed, cystic lesions that most often involve the caruncle. Surgical excision can be curative. Epithelial cells with copious quantities of intensely eosinophilic cytoplasm characterize oncocytic transformation histopathologically.

Lesions of the caruncle: a description of 42 cases and a review of the literature

Lesions of the caruncle are uncommon. On account of the histological composition of the caruncle, which includes, in addition to conjunctiva, hair follicles, sebaceous glands, sweat glands, and accessory lacrimal tissue, the caruncle may develop lesions that may be similar to those found in the skin, conjunctiva, or lacrimal gland. Clinical preoperative diagnosis is very difficult and reached only in about half of the cases. The vast majority of lesions of the caruncle are benign, mainly nevi. Reported malignant lesions are very rare but can be potentially fatal. Although malignancy is clinically overestimated, any suspected malignant lesion should be excised and examined histopathologically by an experienced pathologist. This study presents the clinical and histological data of 42 consecutive caruncular lesions processed at our laboratory and reviews previously reported cases of caruncular lesions.

Oculocutaneous Oncocytic Tumors: Clinicopathologic and Immunohistochemical Study of 2 Cases With Literature Review

Oculocutaneous oncocytic tumors (OCOTs) are uncommon neoplasms that have been reported only rarely in the dermatopathology literature and whose immunophenotypic profile has not been well characterized. The clinical, histologic, and immunophenotypic features of 2 cases seen by the authors were assessed, and relevant publications in the literature were reviewed. Both patients with OCOTs were adult women with gradually enlarging, asymptomatic lesions involving the caruncle; they were locally excised. Histologically, the tumors were well-circumscribed nodules comprised of large oxyphilic cells arranged in confluent sheets and forming glandular spaces with secretory material. Microcystic areas and sparse intermingled goblet-cells were also apparent. Nuclear atypia and infiltrative growth were absent. Mitotic activity was absent in one case; a single mitotic figure was identified in the other. Immunostains demonstrated uniform expression of pankeratin and mitochondrial antigens. Both neoplasms were also labeled for markers associated with cutaneous adnexal, lacrimal, and minor salivary glandular tissue, including alpha-1-antitrypsin, gross cystic disease fluid protein-15, carcinoembryonic antigen, lysozyme and MUC1; each case expressed 4 of the 5 substances. Some cells expressed cytokeratins 5/6 and p63 consistent with the presence of basal-type differentiation in a subset of cells. No definite evidence of myoepithelial differentiation was demonstrated, as stains for smooth muscle actin, muscle-specific actin, and S100 protein were negative. Estrogen and progesterone receptor proteins were absent; strong cytoplasmic immunoreactivity for androgen receptor protein was evident, but nuclear staining was absent. The authors conclude that OCOTs show glandular differentiation. A review of the literature disclosed that none of these lesions arising in the caruncle behaved aggressively, in contrast to occasional tumors in other oculocutaneous sites.

Oncocytoma of the caruncle: a clinicopathologic case report

BACKGROUND

Oncocytoma is an uncommon, relatively benign tumor, composed of transformed epithelial cells of the ducts. We report a case of oncocytoma of the caruncle.

METHODS

Case report.

RESULTS

A 51-year-old woman with a 2 years history of a mass located in the caruncle of her right eye was presented. Surgical excision was then performed, and the histological diagnosis of oncocytoma was established.

CONCLUSION

The oncocytoma should be considered in the differential diagnosis of a caruncular mass in elderly people, particularly in female patients.

Oncocytic metaplasia occurring in melanoma

BACKGROUND

Oncocytosis is a cellular feature characterized by the presence of a finely granular eosinophilic cytoplasm due to the accumulation of mitochondria. While this histologic trait can be found in normal tissues, it is also seen pathologically as a degenerative phenomenon. We recently reviewed a spectrum of oncocytic melanocytic nevi that did not have clinical significance. We now describe similar changes in melanoma.

METHODS

We retrospectively reviewed 12 melanomas noted to have prominent granular eosinophilic cytoplasm and completed ultrastructural studies. We obtained patient histories and clinical follow-up information from the patients' physicians.

RESULTS

All cases were primary melanomas and showed prominent oncocytosis in the majority of the lesional melanoma cells. Oncocytosis was observed in both melanoma in situ and invasive melanoma with a wide range of Breslow thicknesses (range, 0.45-5.05 mm). It occurred in the presence and absence of ulceration, regression, vascular invasion, and brisk tumor infiltrating lymphocytes. Ultrastructural studies revealed melanocytes with numerous distorted mitochondria.

CONCLUSION

Melanoma is capable of presenting in a variety of histologic guises, including oncocytic change. While our observations are preliminary, this pathologic curiosity likely represents a degenerative phenomenon of little prognostic importance.

Oncocytic metaplasia occurring in a spectrum of melanocytic nevi

Oncocytosis is defined as a metaplastic change characterized by the presence of cells with finely granular eosinophilic cytoplasm caused by the accumulation of mitochondria. Although this histologic feature can be found in normal tissues, it can also be seen pathologically as a degenerative phenomenon, where an accumulation of mitochondria is thought to compensate for an uncoupling of oxidative metabolism secondary to cellular aging. Oncocytic metaplasia can be observed in a variety of cutaneous lesions but, to our knowledge, has not been described in melanocytic nevi. We retrospectively reviewed 87 melanocytic nevi from 83 patients that showed significant oncocytic change. We obtained patient clinical history through surveys completed by the patients' physicians. Ultrastructural studies were performed on 4 representative nevi to confirm the presence of increased mitochondria. We prospectively reviewed 100 randomly selected nevi looking for oncocytic changes. We subsequently did not find any correlation with patient demographics or medical histories. Histologic evaluation showed granular eosinophilic cytoplasm in 75% or greater of lesional cells in two thirds of cases. This phenomenon occurred in all types of melanocytic nevi. Ultrastructural studies revealed melanocytes with numerous mitochondria in close apposition to melanosomes. Focal oncocytic change was identified prospectively in 38 of 100 randomly selected melanocytic nevi. We conclude that oncocytosis in melanocytic nevi is a relatively common and underrecognized phenomenon.

Phakomatous choristoma: a case report and review of the literature

Phakomatous choristoma is a rare congenital lesion of the eyelid that can be clinically and/or histologically mistaken for a cyst, cutaneous adnexal neoplasm, or an ocular adnexal oncocytoma. Only 13 such cases have been previously described, mostly in the English language ophthalmic literature. Zimmerman reported the first case in 1971 and proposed the lesion to be of lenticular anlage origin, a theory that has been widely accepted. We report an additional case occurring in an 8-week-old male infant with a firm nodule of the right lower eyelid that was present since birth. A 15 x 12 x 2 mm circumscribed solid nodule with a homogenously white cut surface was surgically excised. Histologically, this lesion was comprised of cuboidal cells forming cystically dilated and irregularly branched ducts and cords within a densely fibrotic stroma. Also present were eosinophilic basement membranelike material, psammoma body-like calcifications and intraluminal degenerated ghost cells. The immunohistochemical profile of the epithelial cells included strong immunoreactivity for vimentin, focal weak staining for S-100, and negative staining for cytokeratin, epithelial membrane antigen, synaptophysin, and chromogranin. The irregularity of the ducts and cords of epithelial cells within the densely fibrotic stroma resembled an infiltrative neoplasm of cutaneous adnexal or lacrimal duct origin. However, the site of involvement, the peculiar basement membrane material, ghost cells, and immunohistochemical profile were features that helped to distinguish phakomatous choristoma from an infiltrative carcinoma. The correct identification of this lesion is essential to avoid an aggressive surgical excision, thus sparing the eyelid and lacrimal system. The purpose of this article is to bring attention to this rare entity, because it has not been described in either the dermatology or dermatopathology literature and furthermore, is not mentioned in any of the major dermatopathology texts.