Non-Epitheliotropic Cutaneous Lymphoma with Systemic Dissemination in a Dog

Background: Cutaneous lymphoma is a highly malignant neoplasm, which can originate in the epidermis or dermis, as well as be disseminated to other organs such as lung, heart, arm, liver and bone marrow. It comes in the form of nodes of various sizes, erythematous and alopecic, itching may or may not occur. The diagnosis is made by cytological and histopathological examination of the compromised tissue. However, it is important to perform complementary tests for clinical staging and prognostic characterization. The objective is to report a case of non-epitheliotropic cutaneous lymphoma with systemic dissemination in a dog.Case: A female mixed bred adult canine was attended at the Veterinary Hospital of the Federal University of Mato Grosso do Sul with a history of progressive weight loss and the presence of alopecic and non-pruritic subcutaneous nodules in the torso, nasal plane and pelvic limbs, starting 4 months ago. After approximately 20 days, the presence of rapidly evolving ulcerated nodules was noted. On physical examination, generalized lymphadenomegaly was observed and among the dermatological findings were multiple nodules of varying sizes with the presence of ulceration in the center of the lesions, alopecia, erythema and raised edges, in the region of the nasal sinus, pelvic and thoracic limbs, tail, thoracolumbar and abdominal region. The animal also presented right pelvic limb edema with painful sensibility to manipulation CBC and biochemical tests (albumin, alanine aminotransferase, creatinine, urea, alkaline phosphatase, globulins, total proteins and fractions) were performed, being observed as normocytic normochromic type anemia alteration (erythrocytes: 2.78 106/µL; hemoglobin: 6.8 g/µL; globular volume: 18.8%), leukopenia (4,000/mm³) with presence of metamyelocytes (120/mm³) and rods (1,080/mm³) and lymphopenia (80/mm³). Three samples of the nodules were collected for histopathological examination and a definitive diagnosis of cutaneous lymphoma was obtained. The material was then submitted to immunohistochemical examination, which showed that it was a non-epitheliotropic cutaneous lymphoma of T immunophenotype. Due to the compromised quality of life and unfavorable prognosis, the owner opted for euthanasia of the animal. In the necropsy examination, lymph nodes, subcutaneous tissue, skeletal muscle, heart, pericardial sac, tongue and multifocal infiltrate of neoplastic cells were observed, findings suggestive of multicentric lymphoma or infiltrations by dissemination of cutaneous lymphoma.Discussion: Non-epitheliotropic skin lymphomas exhibit rapid progression and infiltration into lymph nodes and subsequent systemic involvement. The diagnosis is based on clinical-dermatological signs, fine needle cytology, histopathological and immunohistochemical examination. Normocytic normochromic anemia is the most observed alteration in patients with lymphoma, followed by leukocytosis, leukopenia, thrombocytopenia, neutrophilia and leukoerythroblastic reactions.  Dogs with T-cell lymphoma have a worse prognosis for life span and disease-free intervals than those with B-cell lymphoma, so immunophenotyping is critical to determine prognosis. In the present report, histopathological and immunohistochemical examinations were decisive for the diagnosis of the present report, because the expression CD3 and the negativity for CD79a proved that the neoplasm is of T lymphocyte lineage. The definitive diagnosis was obtained by histopathology, however, immunohistochemistry determined the immunophenotype of the neoplasia as non-epitheliotropic T lymphocyte.

Squamous Cell Carcinoma in the Third Eyelid of a Dog

Background: Squamous cell carcinoma is a malignant neoplasm that originates from the keratinized stratified squamous epithelium and predominantly affect light-skinned animals. In dogs, breeds such as American Staffordshire Terriers, white or speckled Bull Terriers, and Beagles have a higher predisposition. Squamous cell carcinoma presents in the skin, at slightly pigmented or hairy sites, especially in digits, but also may occur in the nasal planum, oral mucosa, and rarely, in the eye. Considering that few reports have been published on eye neoplasms, the aim of this paper is to describe a dog with a lesion in the third eyelid of his right eye which was diagnosticated with squamous cell carcinoma. Case: A 10-year-old male American Staffordshire dog was admitted to the Veterinary Medical Teaching Hospital of the Veterinary Medicine and Zootechnics College, Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, Brazil with injury to the right eye. During the physical examination, there was also a non-adhered lump near the foreskin, measuring 1.5 cm in diameter. In addition, there was another lump in the third eyelid of the right eye, approximately 3 mm in diameter. Cytology of the dermal nodule was performed by fine-needle aspiration cytology; however, the sample was insufficient for cytological evaluation. Therefore, the animal was placed under general anesthesia for skin lump excision and for fine-needle aspiration cytology of the third eyelid nodule. The histopathological exam revealed high cellularity of epithelial cells, intense anisocytosis and pleomorphism, cytoplasmic basophilia and vacuolation, multiple evident nucleoli, and anisocariosis and coarse chromatin. These finds were compatible with squamous cell carcinoma, which was the same result suggested by fine-needle aspiration cytology of the third eyelid sample. Based on these results, the dog underwent a surgical procedure for enucleation and subsequent histopathological evaluation of the nodule in the third eyelid, which confirmed the squamous cell carcinoma diagnosis.Discussion: Squamous cell carcinoma is an extremely aggressive tumor with low metastatic potential, characterized by invasion of the dermis by proliferation of malignant epithelial cells from the prickly layer. It is most common in elderly animals, and American Staffordshires are among the breeds that are predisposed to develop this tumor. The clinical presentation is highly variable, depending on the tissue involved. In this case, the dermal nodule was an elevated area on the skin and the third eyelid nodule resembled an ulcerative mass. Cytological examination from the lesion located on the third eyelid, showed malignancies cytoplasmic changes frequently found in carcinomas such as anisocytosis, cytoplasmic basophilia, and cell pleomorphism. In addition, nuclear changes had also occurred, such as crass chromatin, multiple evident nucleoli, and multinucleated cells. A presumptive diagnosis was made based on cytology and was confirmed after biopsy and histopathological examination. Because it is uncommon in dogs, squamous cell carcinoma of the third eyelid may be misdiagnosed, delaying correct treatment, and accelerating the development of the tumor. Currently, various therapeutic approaches are available, such as surgical excision, electrosurgery, cryosurgery, radiation, and hyperthermia. The choice of treatment depends on the location and stage of the lesions. Surgical treatment should be aimed at removing sufficient tissue to leave surgical margins free of neoplastic cells

Non-Epitheliotropic Cutaneous Lymphoma with Systemic Dissemination in a Dog

Background: Cutaneous lymphoma is a highly malignant neoplasm, which can originate in the epidermis or dermis, as well as be disseminated to other organs such as lung, heart, arm, liver and bone marrow. It comes in the form of nodes of various sizes, erythematous and alopecic, itching may or may not occur. The diagnosis is made by cytological and histopathological examination of the compromised tissue. However, it is important to perform complementary tests for clinical staging and prognostic characterization. The objective is to report a case of non-epitheliotropic cutaneous lymphoma with systemic dissemination in a dog.Case: A female mixed bred adult canine was attended at the Veterinary Hospital of the Federal University of Mato Grosso do Sul with a history of progressive weight loss and the presence of alopecic and non-pruritic subcutaneous nodules in the torso, nasal plane and pelvic limbs, starting 4 months ago. After approximately 20 days, the presence of rapidly evolving ulcerated nodules was noted. On physical examination, generalized lymphadenomegaly was observed and among the dermatological findings were multiple nodules of varying sizes with the presence of ulceration in the center of the lesions, alopecia, erythema and raised edges, in the region of the nasal sinus, pelvic and thoracic limbs, tail, thoracolumbar and abdominal region. The animal also presented right pelvic limb edema with painful sensibility to manipulation CBC and biochemical tests (albumin, alanine aminotransferase, creatinine, urea, alkaline phosphatase, globulins, total proteins and fractions) were performed, being observed as normocytic normochromic type anemia alteration (erythrocytes: 2.78 106/µL; hemoglobin: 6.8 g/µL; globular volume: 18.8%), leukopenia (4,000/mm³) with presence of metamyelocytes (120/mm³) and rods (1,080/mm³) and lymphopenia (80/mm³). Three samples of the nodules were collected for histopathological examination and a definitive diagnosis of cutaneous lymphoma was obtained. The material was then submitted to immunohistochemical examination, which showed that it was a non-epitheliotropic cutaneous lymphoma of T immunophenotype. Due to the compromised quality of life and unfavorable prognosis, the owner opted for euthanasia of the animal. In the necropsy examination, lymph nodes, subcutaneous tissue, skeletal muscle, heart, pericardial sac, tongue and multifocal infiltrate of neoplastic cells were observed, findings suggestive of multicentric lymphoma or infiltrations by dissemination of cutaneous lymphoma.Discussion: Non-epitheliotropic skin lymphomas exhibit rapid progression and infiltration into lymph nodes and subsequent systemic involvement. The diagnosis is based on clinical-dermatological signs, fine needle cytology, histopathological and immunohistochemical examination. Normocytic normochromic anemia is the most observed alteration in patients with lymphoma, followed by leukocytosis, leukopenia, thrombocytopenia, neutrophilia and leukoerythroblastic reactions.  Dogs with T-cell lymphoma have a worse prognosis for life span and disease-free intervals than those with B-cell lymphoma, so immunophenotyping is critical to determine prognosis. In the present report, histopathological and immunohistochemical examinations were decisive for the diagnosis of the present report, because the expression CD3 and the negativity for CD79a proved that the neoplasm is of T lymphocyte lineage. The definitive diagnosis was obtained by histopathology, however, immunohistochemistry determined the immunophenotype of the neoplasia as non-epitheliotropic T lymphocyte.

Squamous Cell Carcinoma in the Third Eyelid of a Dog

Background: Squamous cell carcinoma is a malignant neoplasm that originates from the keratinized stratified squamous epithelium and predominantly affect light-skinned animals. In dogs, breeds such as American Staffordshire Terriers, white or speckled Bull Terriers, and Beagles have a higher predisposition. Squamous cell carcinoma presents in the skin, at slightly pigmented or hairy sites, especially in digits, but also may occur in the nasal planum, oral mucosa, and rarely, in the eye. Considering that few reports have been published on eye neoplasms, the aim of this paper is to describe a dog with a lesion in the third eyelid of his right eye which was diagnosticated with squamous cell carcinoma. Case: A 10-year-old male American Staffordshire dog was admitted to the Veterinary Medical Teaching Hospital of the Veterinary Medicine and Zootechnics College, Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, Brazil with injury to the right eye. During the physical examination, there was also a non-adhered lump near the foreskin, measuring 1.5 cm in diameter. In addition, there was another lump in the third eyelid of the right eye, approximately 3 mm in diameter. Cytology of the dermal nodule was performed by fine-needle aspiration cytology; however, the sample was insufficient for cytological evaluation. Therefore, the animal was placed under general anesthesia for skin lump excision and for fine-needle aspiration cytology of the third eyelid nodule. The histopathological exam revealed high cellularity of epithelial cells, intense anisocytosis and pleomorphism, cytoplasmic basophilia and vacuolation, multiple evident nucleoli, and anisocariosis and coarse chromatin. These finds were compatible with squamous cell carcinoma, which was the same result suggested by fine-needle aspiration cytology of the third eyelid sample. Based on these results, the dog underwent a surgical procedure for enucleation and subsequent histopathological evaluation of the nodule in the third eyelid, which confirmed the squamous cell carcinoma diagnosis.Discussion: Squamous cell carcinoma is an extremely aggressive tumor with low metastatic potential, characterized by invasion of the dermis by proliferation of malignant epithelial cells from the prickly layer. It is most common in elderly animals, and American Staffordshires are among the breeds that are predisposed to develop this tumor. The clinical presentation is highly variable, depending on the tissue involved. In this case, the dermal nodule was an elevated area on the skin and the third eyelid nodule resembled an ulcerative mass. Cytological examination from the lesion located on the third eyelid, showed malignancies cytoplasmic changes frequently found in carcinomas such as anisocytosis, cytoplasmic basophilia, and cell pleomorphism. In addition, nuclear changes had also occurred, such as crass chromatin, multiple evident nucleoli, and multinucleated cells. A presumptive diagnosis was made based on cytology and was confirmed after biopsy and histopathological examination. Because it is uncommon in dogs, squamous cell carcinoma of the third eyelid may be misdiagnosed, delaying correct treatment, and accelerating the development of the tumor. Currently, various therapeutic approaches are available, such as surgical excision, electrosurgery, cryosurgery, radiation, and hyperthermia. The choice of treatment depends on the location and stage of the lesions. Surgical treatment should be aimed at removing sufficient tissue to leave surgical margins free of neoplastic cells