Evaluation of adjuvant chemotherapy in feline injection site-associated sarcoma / Avaliação da quimioterapia no tratamento do sarcoma de aplicação felino

Feline Injection Site-Associated Sarcoma (FISS) is a neoplasm that implies in reduction of quality of life and overall survival in feline patients. A retrospective study of 13 cases of FISS was conducted to evaluate the efficacy of surgical treatment associated to chemotherapy with doxorubicin or carboplatin. Local recurrence occurred in all patients. Patients treated with surgery and chemotherapy presented a longer overall survival and disease-free interval when compared to those that solely received surgical treatment, although no statistical significance was observed (p= 0.3360 and 0.7506, respectively). Surgery remains as the main option for FISS treatment. Further prospective studies with larger samples are warranted to investigate the benefit of chemotherapy for this neoplasm.(AU)

O Sarcoma de Aplicação Felino (SAF) é uma neoplasia associada a redução na qualidade de vida e sobrevida global. O objetivo deste estudo foi avaliar a eficácia da quimioterapia associada à cirurgia no manejo do SAF. Estudo retrospectivo de 13 pacientes com SAF submetidos à cirurgia isolada ou associada a quimioterapia com carboplatina ou doxorrubicina. Recorrência local ocorreu em todos os pacientes. Pacientes tratados com cirurgia e quimioterapia apresentaram maior sobrevida global e intervalo livre de doença quando comparados àqueles que receberam apenas tratamento cirúrgico, mas não foi observada diferença estatística (p=0,3360 e 0,7506, respectivamente). A cirurgia continua sendo a principal opção para o tratamento do SAF. Estudos prospectivos são necessários para investigação do real benefício da quimioterapia para esta neoplasia.(AU)

Fine-needle aspiration cytology and immunocytochemistry of soft-tissue tumors and osteo/chondrosarcomas of the head and neck.

The purpose of the study was to present the clinical and cytological findings of 28 cases of malignant or borderline mesenchymal tumors of the head and neck, of which 22 originated from soft tissue and 6 were found in bone or cartilage. The basic procedures employed involved a cytologic review and subclassification of fine-needle aspiration (FNA) smears from the tumors, which were diagnosed as: pleomorphic sarcomas (5 poorly differentiated, 1 angiosarcoma, and 1 epithelioid sarcoma), spindle-cell sarcomas (2 leiomyosarcomas, 2 malignant mesenchymal tumors, and 1 malignant schwannoma), myxoid sarcomas (2 liposarcomas and 1 high-grade tumor), round-cell tumors (1 malignant histiocytic tumor and 1 chloroma), osteosarcomas (3), chondrosarcomas (3), and borderline tumors (2 pleomorphic lipoma, 1 myxolipoma, 1 cranial fasciitis, and 1 fibromatosis). Histological correlation and problems in subtyping on both cytologic and histological material are discussed. It is concluded that FNA cytology can be used with high accuracy to diagnose musculoskeletal tumors in rare sites such as the head and neck.

A novel role for the peritrophic matrix in protecting Leishmania from the hydrolytic activities of the sand fly midgut.

The role of the peritrophic matrix (PM) in the development of Leishmania major infections in a natural vector, Phlebotomus papatasi, was investigated by addition of exogenous chitinase to the bloodmeal, which completely blocked PM formation. Surprisingly, the absence of the PM was associated with the loss of midgut infections. The chitinase was not directly toxic to the parasite, nor were midgut infections lost due to premature expulsion of the bloodmeal. Most parasites were killed in chitinase-treated flies within the first 4 h after feeding. Substantial early killing was also observed in control flies, suggesting that the lack of PM exacerbates lethal conditions which normally exist in the blood-fed midgut. Early parasite mortality was reversed by soybean trypsin inhibitor. Allosamadin, a specific inhibitor of chitinase, led to a thickening of the PM, and also prevented the early parasite mortality seen in infected flies. Susceptibility to gut proteases was extremely high in transitional-stage parasites, while amastigotes and fully transformed promastigotes were relatively resistant. A novel role for the PM in promoting parasite survival is suggested, in which the PM creates a barrier to the rapid diffusion of digestive enzymes, and limits the exposure of parasites to these enzymes during the time when they are especially vulnerable to proteolytic damage.