Aggressive squamous cell carcinoma of the cranium of a dog

Abstract

Background The authors report a case of keratinized squamous cell carcinoma (SCC) in a 14-year-old dog with extensive cranial bone invasion. To our knowledge, this is the first description of such a case of cranial keratinized SCC with aggressive generalized osteolysis described in a dog. Case presentation The 14-year-old dog was referred for radiological examination with suspicion of head trauma with clinical signs of head deformation, exophthalmos and nasal discharge. The skull radiographs showed a large osteolytic defect of the frontal bone and parietal bone in the region of the external sagittal crest. Findings from the skull CT scan included generalized osteolysis in the region of parietal bone, frontal bones, maxilla on the right side and the nasal bone including the dorsal nasal concha. In the area of bone loss, new soft tissue formation with multifocal foci of mineralization was visible. The ultrasound examination revealed hypoechogenic changes with hyperechoic foci consistent with mineralization and poor vascularization. The brain and ocular structures were without visible changes. Fine needle aspiration cytology (FNAC) was performed, and squamous cell carcinoma was suspected. After 3 months, the re-presented to the clinic. The dog became progressively listless, his appetite was decreased, and he became acutely blind. Follow-up skull CT scan revealed significant osteolysis, which affected a significant aspect of the cranium. All bone defects had been replaced by new 3.5 cm-thick soft tissue formations with multifocal small 1–2 mm areas of mineralization. There was no evidence of metastasis. Histological examination confirmed the suspicion of squamous cell carcinoma. Conclusions This paper is the first report of cranial SCC in a dog causing extensive bone osteolysis. The lesions in this dog originated from the frontal and parietal bones including frontal sinuses. There are variants of tumors that arise from squamous epithelium or resemble SCC in the skull. These examples include adenosquamous carcinoma and proliferating trichilemmal tumours. In addition, there is possible malignant transformation caused by papilloma viruses. In the veterinary literature, there is only one similar description of adenosquamous carcinoma in a cat with similar clinical manifestations. It is justified to suspect a process of neoplastic epithelial origin in all cases of aggressive and extensive skull bone lysis. This issue should be subject to further investigation.

Recurrent Squamous Cell Carcinoma of the Submandibular Region after Surgery in a Dog: A Case Report

“…The same year saw reports on cutaneous cases in mixed-breed dogs, American pit bulls, boxers, and English pointers (Dos Anjos et al, 2019). From 2020 to 2021, there were reports of SCC in the cranium and oral cavity (Simčič et al, 2020;Łojszczyk et al, 2021). In the current case study, SCC was near the left submandibular region of a dog, which is rarely found.…”

“…As previously reported, SCC is commonly found in dogs with an average age of 8.8 years (Willcox et al, 2019). In addition, some previous reports found an average age of 10 years (Lascelles et al, 2000), but the condition can be found from 4 months to 14 years of age (Łojszczyk et al, 2021;Sharma et al, 2021). The effect of gender on cases of SCC is unclear.…”

“…Furthermore, SCC has been reported in other species, including cats, horses, and chinchillas (Thomson, 2007;Morrison et al, 2019;Szabo et al, 2019). The predisposing factors that cause SCC include exposure to ultraviolet light, contact with chemical carcinogens, chronic inflammation, and viral infection (Munday et al, 2017;Łojszczyk et al, 2021). In addition, previous studies found that the papillomavirus causes immunosuppression and induces epithelial malignant progression (Munday et al, 2017).…”

“…Squamous cell carcinoma (SCC) originates from squamous epithelium, and is a malignant tumor (Willcox et al, 2019). This type of tumor in dogs has been reported in several organs, such as the cranium, cornea, rostral nasal septum, and oral cavity, while it has also occurred cutaneously (Dos Anjos et al, 2019;Simčič et al, 2020;Łojszczyk et al, 2021). Furthermore, SCC has been reported in other species, including cats, horses, and chinchillas (Thomson, 2007;Morrison et al, 2019;Szabo et al, 2019).…”

Cerebral meningioma associated with extensive calvarium osteolysis and presumed intratumoral carcinoma metastasis in a cat

“…Although the meningioma most likely induced the skull osteolysis reported here, it is important to mention the presence of the presumed adenocarcinomatous metastasis in this case, which might also have played a role in the lytic process. Indeed, other tumour types or pathological conditions inducing skull osteolysis have been reported in dogs and cats, such as squamous cell carcinoma, 14 choroid plexus carcinoma, 15 glioma, 16 pulmonary adenosquamous carcinoma metastases, 17 skull osteomyelitis 18 and intra cranial epidural tuberculoma. 19 In human medicine, osteolysis associated with intracranial meningiomas is a very rare finding and might be related to type 2 matrix metalloproteinase (MMP) expression.…”