Las células claras en el carcinoma espinocelular cutáneo

Acantholytic oral squamous cell carcinoma with clear cell change - a rare amalgamated variant

Background

Acantholytic squamous cell carcinoma (ASCC) is an uncommon histological variation of oral squamous cell carcinoma (OSCC), accounting for fewer than 4% of all occurrences. The tumor shows a slight masculine predisposition, with the lower lip being the most commonly affected location. ASCC is reported to have a diverse biologic behavior, which explains its ability to metastasize to distant places and, thus, its poor prognosis. Similarly, clear cell change in OSCC is a rare occurrence with an unknown etiology that suggests its aggressive nature.

Method and Results

Histopathology reveals central acantholytic cells with numerous duct-like features. The presence of distinct cytological atypia contributes to the diagnosis of SCC. Special stains and IHC aid in distinguishing tumor from other histopathologically similar entities.

Conclusion

The case of a 29-year-old male presented here with an updated literature review highlights the need for histological study of the unique and seldom seen oral ASCC with clear cell change, which can be ignored because of similarities with other entities. Because recurrence rates are so high for ASCC, amalgamated clear cell change makes it critical for proper treatment initiation with a definite diagnosis. To the best of our knowledge, this is the first documented occurrence. Our experience with the present case suspected a more aggressive behavior due to a high Ki-67 index, anticipating a poorer prognosis in the oral cavity considering the patient's young age.

Clear Cell Proliferations of the Skin: A Histopathologic Review

ABSTRACT

Cutaneous clear cell proliferations encompass a heterogenous group of several primary cutaneous neoplasms and metastatic tumors with different histogenesis. Many of these clear cell proliferations may seem strikingly similar under the microscope resulting in challenging diagnosis. In many of these clear cell lesions, the reason for the clear or pale appearance of proliferating cells is unknown, whereas in other ones, this clear cell appearance is due to intracytoplasmic accumulation of glycogen, mucin, or lipid. Artifacts of tissue processing and degenerative phenomenon may also be responsible for the clear cell appearance of proliferating cells. Awareness of the histopathologic findings as well as histochemical and immunohistochemical techniques are crucial to the accurate diagnosis. This review details the histopathologic features of clear cell cutaneous proliferations, classifying them according their type of differentiation and paying special attention to the histopathologic differential diagnosis among them.

Squamous cell carcinoma with clear cell differentiation in an equine eyelid

A 15-y-old Miniature horse mare had a 6-mo history of an ulcerated mass on the right lower eyelid. An incisional biopsy and a subsequent excisional biopsy were submitted to the Michigan State University Veterinary Diagnostic Laboratory for microscopic evaluation. Histologically, the incisional biopsy was composed of sheets of large neoplastic vacuolated polygonal cells. A few regions contained poorly differentiated neoplastic round-to-basaloid cells that rimmed the sheets of highly vacuolated polygonal cells. Both vacuolated and basaloid cells exhibited strong perimembranous and cytoplasmic immunoreactivity for E-cadherin and cytokeratin 5/6, respectively. Vacuolated polygonal cells were histochemically negative for periodic acid-Schiff, mucicarmine, and oil red O, consistent with a diagnosis of poorly differentiated carcinoma. Within the excisional biopsy specimen, there were anastomosing cords and nests of neoplastic squamous epithelial cells that merged with sheets of similar vacuolated polygonal cells. These findings are consistent with a squamous cell carcinoma with clear cell differentiation. In addition, in the adjacent dermis, there was solar elastosis suggestive of ultraviolet (UV) damage. A clear cell variant of squamous cell carcinoma is a rare entity in humans that previously has not been described in animals, to our knowledge, and is often associated with chronic UV exposure.

Lobulated Bowen's Disease with a Clear Cell Change

Bowen's disease usually manifests as a slowly enlarging erythematous scaly patch or plaque. An uncommon variant of Bowen's disease showing a verrucous appearance has been reported and a distinct variant with a prominent clear cell change on histopathology, in addition to a verrucous surface change, was also reported. We describe novel form of Bowen's disease having a cerebriform appearance and showing histopathologically a significant clear cell change and propose that the clinical term "lobulated Bowen's disease" would be compatible for the description of this unique clinical variant. From a histopathological point of view, the precise definition and etiopathogenesis of the clear cell change in Bowen's disease should be elucidated.