Canine conjunctival mast cell tumors: a retrospective study

The purpose of this study was to determine if the presence of histopathologically tumor-free versus nontumor-free margins was prognostic for relapse or tumor-related death in dogs following surgical excision of single or multiple cutaneous mast cell tumors confined to the skin without evidence of metastasis to lymph nodes or other noncutaneous sites. Differences in tumor-related death or frequency of relapse between the two groups were not significant. Failure to achieve histopathological tumor-free margins frequently did not lead to local relapse. All tumor-related deaths occurred following local relapse. The lack of statistical support for an association between prognosis and histopathological tumor-free versus nontumor-free margins may be a result of small sample size.

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Use of different fixation times and application of two immunohistochemical methods for detection of KIT and Ki67 proteins in canine cutaneous mast cell tumors

Pesquisa Veterinária Brasileira ◽

10.1590/1678-5150-pvb-5843 ◽

2019 ◽

Vol 39 (1) ◽

pp. 52-60

Author(s):

Alex dos Santos ◽

Harlan H.L. Nascimento ◽

Mariana M. Flores ◽

Glaucia D. Kommers

Keyword(s):

Mast Cell ◽

Retrospective Study ◽

Prospective Study ◽

Biological Behavior ◽

Growth Fraction ◽

Fixation Time ◽

Mast Cell Tumors ◽

Grading Systems ◽

High Prevalence ◽

Cutaneous Mast Cell

ABSTRACT: Due to the high prevalence of mast cell tumors (MCTs) in the diagnostic routine, several factors, especially prognostic, have been sought to determine the biological behavior of these neoplasms. Immunohistochemistry (IHC) is one of the main tools utilized to biologically differentiate more aggressive tumors from less aggressive ones. However, some immunostainings are influenced by formalin fixation, interfering with the results. This is both a retrospective and prospective study of MCTs diagnosed in laboratory routine. A total of 25 samples, without knowledge about fixation time, were analyzed in the retrospective study, whereas 12 samples, with known fixation times, were assessed in the prospective study. Two histologic grading systems (Patnaik and Kiupel), special staining of toluidine blue, and IHC for KIT and Ki67 proteins were applied in both studies. Additionally, two amplification systems (biotinylated and non-biotinylated) for Ki67 protein and counting of the argyrophilic nucleolar organizing regions (AgNOR method) were tested in the prospective study. In the retrospective study, greater agreement between the evaluating pathologists was observed when the Kiupel system was used. IHC staining for KIT protein was effective in both studies, regardless of fixation time. IHC staining for Ki67 protein was highly sensitive to formaldehyde, and staining failure was observed in 56% of the cases in the retrospective study. In the prospective study, samples fixed for longer than 24 hours showed a reduction in the number of stained cells (altering the determination of the cell growth fraction) or showed absence of IHC staining in both amplification systems. The use of the AgNOR method to evaluate the rate of cell proliferation may be an alternative when the fixation time of the neoplasm is unknown or longer than 24 hours.

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Nonhematopoietic Gastrointestinal Neoplasia in Cats: A Retrospective Study of 44 Cases

Veterinary Pathology ◽

10.1177/030098588101800506 ◽

1981 ◽

Vol 18 (5) ◽

pp. 614-620 ◽

Cited By ~ 44

Author(s):

M. A. M. Turk ◽

A. M. Gallina ◽

T. S. Russell

Keyword(s):

Mast Cell ◽

Retrospective Study ◽

Undifferentiated Carcinoma ◽

The Other ◽

Gastrointestinal Neoplasms ◽

Tubular Adenocarcinoma ◽

Animal Disease ◽

Diagnostic Laboratory ◽

Mast Cell Tumors ◽

Chondroid Metaplasia

Gastrointestinal neoplasms other than lymphosarcomas and mast cell tumors were diagnosed in 44 cats during a 14-year period at the Washington Animal Disease Diagnostic Laboratory. All the tumors were malignant; 31 metastasized or recurred. One cat had fibrosarcoma; another, leiomyosarcoma. The other 42 cats had adenocarcinomas, which were subclassified into three histologic patterns: tubular adenocarcinoma; undifferentiated carcinoma; and mucinous adenocarcinoma. The cats averaged 10.6 years of age. There was no sex predisposition. Siamese cats had a higher frequency of adenocarcinomas than other breeds. Osseous and chondroid metaplasia occurred in nine adenocarcinomas.

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Expression of KIT Receptor in Feline Cutaneous Mast Cell Tumors

Veterinary Pathology ◽

10.1354/vp.08-vp-0084-r-fl ◽

2009 ◽

Vol 46 (5) ◽

pp. 878-883 ◽

Cited By ~ 20

Author(s):

C. Rodríguez-Cariño ◽

D. Fondevila ◽

J. Segalés ◽

R. M. Rabanal

Keyword(s):

Mast Cell ◽

Retrospective Study ◽

Toluidine Blue ◽

Cellular Location ◽

Mast Cell Tumors ◽

Kit Receptor ◽

Hematoxylin And Eosin ◽

Cutaneous Mast Cell ◽

Well Differentiated ◽

Diffuse Distribution

Twenty-seven feline cutaneous mast cell tumors (MCTs) were selected for this retrospective study. Samples were routinely processed and stained with hematoxylin and eosin (HE) and toluidine blue, and tumors were classified as well-differentiated (19/27), atypical or poorly granulate (7/27), and pleomorphic (1/27). Immunohistochemistry to detect KIT protein was performed on all samples. The immunoreactivity was recorded by distribution within the tumor, cellular location, and intensity. Well-differentiated MCTs were predominantly characterized by diffuse cytoplasmic (8/19) and membranous stain (7/19); a diffuse distribution of KIT positive cells was displayed in most of these tumors as well (15/19). Atypical MCTs showed diffuse distribution of labeled cells (4/7), and diffuse cytoplasm immunostaining was seen most (5/7). The pleomorphic MCT showed diffuse cytoplasmic KIT stain, with moderate labeling intensity, typically displaying focal distribution in deeper areas of the neoplasm. According to the results, there was no correlation between the type of MCTs and KIT expression, although the use of feline KIT immunohistochemistry could be useful to assess the mast cell origin.

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Immunohistochemical Expression of Vascular Endothelial Growth Factor as a Prognostic Marker for Canine Mast Cell Tumors

Topics in Companion Animal Medicine ◽

10.1016/j.tcam.2020.100506 ◽

2021 ◽

Vol 42 ◽

pp. 100506

Author(s):

Samanta Rios Melo ◽

Eric Vieira Januário ◽

Erika Zanuto ◽

Bruna de Castro Miranda ◽

Thais Rodrigues Macedo ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Mast Cell ◽

Growth Factor ◽

Prognostic Marker ◽

Vascular Endothelial ◽

Immunohistochemical Expression ◽

Mast Cell Tumors ◽

Endothelial Growth Factor

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Stereology in Grading and Prognosis of Canine Cutaneous Mast Cell Tumors

Veterinary Pathology ◽

10.1177/0300985820985138 ◽

2021 ◽

pp. 030098582098513

Author(s):

Mafalda Casanova ◽

Sandra Branco ◽

Inês Berenguer Veiga ◽

André Barros ◽

Pedro Faísca

Keyword(s):

Mast Cell ◽

Clinical Outcome ◽

Prognostic Value ◽

Histological Grade ◽

Intraobserver Variability ◽

Low Grade ◽

High Grade ◽

Mast Cell Tumors ◽

Cutaneous Mast Cell ◽

Grade Iii

Canine cutaneous mast cell tumors (ccMCTs) are currently graded according to Patnaik and Kiupel grading schemes. The qualitative and semiquantitative parameters applied in these schemes may lead to inter- and intraobserver variability. This study investigates the prognostic value of volume-weighted mean nuclear volume ([Formula: see text]), a stereological estimation that provides information about nuclear size and its variability. [Formula: see text] of 55 ccMCTs was estimated using the “point-sampled intercept” method and compared with histological grade and clinical outcome. The clinical history of dogs treated with surgical excision alone was available for 30 ccMCTs. Statistical differences in [Formula: see text] were found between grade II ([Formula: see text]= 115 ± 29 µm3) and grade III ccMCTs ([Formula: see text]= 197 ± 63 µm3), as well as between low-grade ([Formula: see text]= 113 ± 28 µm3) and high-grade ccMCTs ([Formula: see text]= 184 ± 63 µm3). An optimal cutoff value of [Formula: see text] ≥ 150 µm3 and [Formula: see text] ≥ 140 µm3 was determined for grade III and high-grade ccMCTs, respectively. In terms of prognosis, [Formula: see text] was not able to predict the clinical outcome in 42% of the cases; however, cases with [Formula: see text]<125 µm3 had a favorable outcome. These results indicate that, despite having limited prognostic value when used as a solitary parameter, [Formula: see text] is highly reproducible and is associated with histological grade as well as with benign behavior.

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