Malignant changes in a giant orbital keratoacanthoma developing over 25 years

Abstract

ABSTRACT.Purpose: To report a patient with a history over 25 years of a slowly growing, large, invasive crateriform tumour filling the anterior part of the orbit. Methods: A 61-year-old male presented with a large tumour of the left orbit. Exenteration was performed with subsequent histological analysis of the excised mass. Results:The main tumour showed the characteristic features of a keratoacanthoma. However, the posterior aspect of the tumour disclosed the morphology of a squamous cell carcinoma. Six months later, the patient presented with metastases to lymph nodes, lung and mediastinal tissue. A leukemoid reaction was diagnosed by fine needle biopsy. Conclusion:The giant variety of keratoacanthoma may fail to regress and can transform into a squamous cell carcinoma. In our patient, the development of a chronic lymphoid leukemia raises the possibility that it may be the underlying cause for the transformation of the posterior part of the keratoacanthoma into a frank squamous cell carcinoma.

Keratoacanthoma of the spectacle in a Boa constrictor

“…Amongst small animals KA seems to be uncommon in the dog and even more infrequently in the cat 15 . KA in humans is a well documented epithelial tumor with a predilection for the head 16,17 . To the authors’ knowledge keratoacanthoma has not been described in reptiles in general, or of the spectacle.…”

“…15 KA in humans is a well documented epithelial tumor with a predilection for the head. 16,17 To the authors' knowledge keratoacanthoma has not been described in reptiles in general, or of the spectacle.…”

Head and neck giant keratoacanthoma: a case report

“…The histopathological diagnosis of KA is further complicated by its histological similarities with the squamous cell carcinoma. 2,3,5 Histopathological features vary with the stage of evolution. 3 An early lesion is reported to increase rapidly, generating cell differentiation with a high proliferation index.…”

“…Keratoacanthoma (KA) is a rapid growth tumor characterized by its composition of well-differentiated keratinizing squamous cells, which originate from the pilosebaceous follicles, and its etiology is not identified. [1][2][3][4] It is commonly presented as a self-limiting lesion and has strong clinical and histopathological similarities with squamous cell carcinoma. 2,3,6 Head and neck KAs are common and account for around 70% of all KAs.…”

“…[1][2][3][4] It is commonly presented as a self-limiting lesion and has strong clinical and histopathological similarities with squamous cell carcinoma. 2,3,6 Head and neck KAs are common and account for around 70% of all KAs. 1,3 Classically, the lesion is presented as a domeshaped nodule with an ulcerated crater in its center.…”