Sumeyye TOYGA(1), Evrim EGEDEN(2), Gulay YUZBASIOGLU OZTURK(3), Funda YILDIRIM(3), Zuleyha AKGUN(4)
(1)Istanbul University-Cerrahpasa, Faculty of Veterinary Medicine, Graduate School of Educa?on, Department of Pathology, Buyukcekmece, 34500, Istanbul, Turkey. (2)Ada Veterinary Clinic, Besiktas, 34330 Istanbul, Turkey.
(3)Istanbul University-Cerrahpasa Faculty of Veterinary Medicine, Department of Pathology, Buyukcekmece, 34500 Istanbul, Turkey.
(4)Istanbul Bilgi University, Department of Radiation Oncology, Sisli, 34060, Istanbul, Turkey.
E-Mail: toygasumeyye@gmail.com
INTRODUCTION
Nasal lymphoma is the most common nasal tumor in cats. Cats with nasal lymphoma show respiratory clinical signs, including runny nose, epistaxis, dyspnea, facial deformities, anorexia, and buphthalmia. Histopathology, as well as immunohistochemical methods, plays an important role in the diagnosis of nasal lymphoma. Histopathologically, nasal lymphoma in cats is usually high grade, and cases of feline nasal lymphoma are generally reported to be B-cell lymphoma. Radiotherapy, chemotherapy, and their combination are used as a treatment for feline nasal lymphoma tumors. The surgical method is not preferred because it is difficult to reach the area anatomically. In general, nasal lymphoma cases are sensitive to radiotherapy, and there are studies on a favorable prognosis and average survival time in cases treated with radiotherapy. In this case report, it is aimed to specify the clinicopathological features of feline nasal lymphoma tumor, to contribute to the current literature knowledge with diagnostic histomorphological and immunohistochemical distinction and combined therapy of radiotherapy and chemotherapy.
MATERIAL-METHOD
The case is a 7-year-old female tricolor cat with a mass in the nasal region. Physical examination revealed hyperplasic neoplasia from the right maxillary region to the frontal region, including the nasal cavity, and associated deformation (FIGURE 1A).
Figure 1.A Hyperplasic neoplasia and related deformation were observed from the right maxillary region to the frontal region including the nasal cavity.
Monocytosis and severe anemia were detected in the complete blood count and serum biochemical analysis (IDEXX Catalyst Dx® Biochemical Analyzer, IDEXX ProCyte® Hematology Analyzer). The blood group of the patient whose medical treatment was started was determined (Alvedia Quick test CT). Medical treatment for blood values was applied for premedication. With the improvement of the clinical findings, a biopsy sample was taken under general anesthesia. After the samples were fixed in 10% formaldehyde solution, they were subjected to routine tissue follow-up processes, embedded in paraffin blocks, tissue sections taken with a thickness of 4-5 μm were stained with Hematoxylin & Eosin (H&E) and examined histopathologically. Extra sections were taken on poly-L lysin-coated slides and immunohistochemically marked with vimentin, cytokeratin, CD79A, CD3, and PCNA antibodies using the Streptavidin-Biotin method. The case with a diagnosis of B-cell nasal lymphoma was scanned under general anesthesia with Computed Tomography (CT) for metastasis investigation and target volume determination, for radiotherapy planning.
FINDINGS CLINICAL AND RADIOGRAPHIC FINDINGS
In the clinical examination of the case, hyperemic areas were observed in places where a neoplastic mass reaching from the right maxilla to the frontal sinus formed facial deformation and formed pseudopigmentation in the region (FIGURE 1B).
In the clinical examination of the case, hyperemic areas were observed in places where a neoplastic mass reaching from the right maxilla to the frontal sinus formed facial deformation and formed pseudopigmentation in the region (FIGURE 1B).
Figure 1.B
Hyperemic areas where it forms pseudo pigmentation
Figure 1.C Image after the first radiotherapy session
It was determined that the nasal cavity was much larger than normal and its regular appearance had completely changed, and the mass in the nasal cavity caused dyspnea and stertor symptoms. Medical treatment was initiated in the intensive care unit for the patient, who had lethargy due to rapid weight loss due to anorexia and severe anemia accompanied by monocytosis in the hematological examination. After a histopathological diagnosis was made, a CT scan was performed to calculate the lesion borders, and target volume for radiotherapy and to control metastasis.
HISTOPATHOLOGICAL FINDINGS
The neoplasm was composed of densely packed sheets and rows of neoplastic cells supported by a thin fibrovascular stroma. The neoplastic cells were large with a moderate amount of eosinophilic cytoplasm and indistinct cell borders. The nuclei were round to ovoid in shape, vesicular, and contained centrally located prominent nucleoli (FIGURE 2A and 2B).
Figure 2. Histopathology of nasal lymphoma. H&E. (A). Celularluy dense neoplasm composed of densely packed sheets and rows of large, round to ovoid shaped neoplastic cells with indistinct cell borders and eosinophilic cytoplasm. 100X Bar=100 μm (B). Neoplastic cells have round to ovoid shaped vesicular nuclei with prominent nucleolus (arrowheads). Atypical mitotic figures (arrows). 600x Bar=20 μm
Marked anisocytosis and anisokaryosis were present with several mitotic figures. Immunohistochemically diffuse and strong expression of CD79A (FIGURE 3A) and vimentin (FIGURE 3B) were seen in neoplastic cells. CD3 and cytokeratin expression were remarkably negative. The tumor was diagnosed as diffuse large B cell lymphoma according to morphological findings and immunohistochemical profile.
Figure 3. Immunohistochemistry of nasal lymphoma. 200X Bar= 20 μm (A) Strong and diffuse expression of vimentin. (B) Diffuse CD79 expression in neoplsatic cell cytoplasms.
TREATMENT
45 cc blood transfusion from a suitable donor was applied to our patient with B blood group, whose clinical findings were severe. Medical treatment for blood values was applied for premedication. After the improvement of his general condition and hematological values with treatment, a radiotherapy protocol was created based on the literature for the patient who underwent a CT scan. Radiotherapy sessions consisted of twelve fractions of 300 cGy on Mondays, Wednesdays, and Fridays[3]. The target volume was determined by images obtained from the patient’s computed tomography. The planning target volume included a 3 cm margin around the clinical target volume. Radiation was given as VMAT technique with 6MV beams on a Truebeam STX (Varian Medical Systems) machine. Immobilization was performed with a thermoplastic mask under anesthesia (FIGURE 4).
45 cc blood transfusion from a suitable donor was applied to our patient with B blood group, whose clinical findings were severe. Medical treatment for blood values was applied for premedication. After the improvement of his general condition and hematological values with treatment, a radiotherapy protocol was created based on the literature for the patient who underwent a CT scan. Radiotherapy sessions consisted of twelve fractions of 300 cGy on Mondays, Wednesdays, and Fridays[3]. The target volume was determined by images obtained from the patient’s computed tomography. The planning target volume included a 3 cm margin around the clinical target volume. Radiation was given as VMAT technique with 6MV beams on a Truebeam STX (Varian Medical Systems) machine. Immobilization was performed with a thermoplastic mask under anesthesia (FIGURE 4).
After the radiotherapy sessions were over, the neoplastic mass also regressed and the clinical course of the case was positive, but the treatment was continued with chemotherapy for the possibility of recurrence of the malignant neoplasia. Chemotherapy protocol CHOP depot steroid was administered over a period of 34 weeks (FIGURE 5). Complete blood count was done within 24 hours before chemotherapy applications. If the patient had neutropenia (Neutrophil count ≤ 2.000 cells/μl), Thrombocytopenia (Platelet count ≤ 50,000 cells/μl), and digestive system problems due to previous chemotherapy, the chemotherapy session was postponed for 3-7 days and complete blood count was performed again.
DISCUSSION-CONCLUSION
Information on the classification and treatment of highly malignant and common nasal lymphoma cases in cats is still limited. This situation makes it difficult to establish the most effective treatment against these neoplasms today. We think that chemotherapy and radiotherapy, which are known treatment methods, are effective for lymphoma in cats, but the combined radiochemotherapy protocol is an optimized method that will reduce the possibility of possible recurrence due to both its well-tolerated and progressive character of cat nasal tumors. We believe that our case diagnosed with B-cell high-grade nasal lymphoma, whose clinical symptoms have decreased since the beginning of the treatment and whose quality of life has increased, can contribute to the science of veterinary oncology by achieving a 455-day remission in the combined treatment of radiotherapy and chemotherapy.REFERENCE [1] Valli V, Bienzle D, Meuten D. Tumours of the hemolymphatic system. In: Meuten D, ed. Tumours in Domestic Animals. Ames, IA: John Wiley; 2017: 203–210. [2] Nakazawa M, Tomiyasu H, Suzuki K, Asada H, Fujiwara-Igarashi A, Goto-Koshino Y, Ohmi A, Ohno K, Fujita M, Tsujimoto H. Efficacy of chemotherapy and palliative hypofractionated radiotherapy for cats with nasal lymphoma. J. Vet. Med. Sci. 83(3): 456–460, 2021
Information on the classification and treatment of highly malignant and common nasal lymphoma cases in cats is still limited. This situation makes it difficult to establish the most effective treatment against these neoplasms today. We think that chemotherapy and radiotherapy, which are known treatment methods, are effective for lymphoma in cats, but the combined radiochemotherapy protocol is an optimized method that will reduce the possibility of possible recurrence due to both its well-tolerated and progressive character of cat nasal tumors. We believe that our case diagnosed with B-cell high-grade nasal lymphoma, whose clinical symptoms have decreased since the beginning of the treatment and whose quality of life has increased, can contribute to the science of veterinary oncology by achieving a 455-day remission in the combined treatment of radiotherapy and chemotherapy.REFERENCE [1] Valli V, Bienzle D, Meuten D. Tumours of the hemolymphatic system. In: Meuten D, ed. Tumours in Domestic Animals. Ames, IA: John Wiley; 2017: 203–210. [2] Nakazawa M, Tomiyasu H, Suzuki K, Asada H, Fujiwara-Igarashi A, Goto-Koshino Y, Ohmi A, Ohno K, Fujita M, Tsujimoto H. Efficacy of chemotherapy and palliative hypofractionated radiotherapy for cats with nasal lymphoma. J. Vet. Med. Sci. 83(3): 456–460, 2021
[3] Cunha S, Corgozinho K, Ferreria A. Treatment of Two Cats with Advanced Nasal Lymphoma with Orthovoltage Radiation Therapy and Systemic Chemotherapy. Acta Scientiae Veterinariae, 2016. 44(Suppl 1): 180.
