Open Journal of Veterinary Medicine, 2012, 2, 216-224
http://dx.doi.org/10.4236/ojvm.2012.24034 Published Online December 2012 (http://www.SciRP.org/journal/ojvm)
Evaluation of Collection and Distribution of Samples for
Histological, Stereological Analysis and Cell Culture of
Canine Mast Cell Tumors
*
Samanta Rios Melo, Thaís Andrade Costa-Casagrande, Julia Maria Matera
Department of Surgery, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
Email: samymelo@usp.br
Received September 5, 2012; revised November 1, 2012; accepted November 12, 2012
ABSTRACT
Objective: To collect high quality, representative tissue material from tumors and manage its distribution to different
laboratories. Design: Prospective controlled study. Animals: Thirty-six dogs with mast cell tumors. Procedures: The
samples were submitted for the following analyses: stereology; histopathology; cell culture; breakdown for cytogenetic
analysis of chromosomes (based on the Boxer breed published genome); Cell lysis for Real Time PCR and quantifica-
tion of gene expression of CX 43, 32 and E-cadherin in canine mast cells. Results: Cytogenetic chromosome analysis,
90.9% of the samples were considered to be of good quality. For gene expression quantification of CX 43, 32 and
E-cadherin in canine mast cell tumors (MCT), 95.5% of samples were considered to be of good quality. Conclusions
and Clinical Relevance: We seek to assess the importance of surgical collection and post-surgical tissue preparation on
laboratory testing by collecting surgical material appropriately to allow accurate diagnosis and reliable clinical progno-
sis and minimize errors caused by inadequate preparation of samples.
Keywords: Mast Cell Tumor; Oncologic Surgery; Canine; Tumor Collection; Stereological Analysis
1. Introduction
Mast cell tumors are common neoplasia in small animals.
This type of neoplasm occurs in several species, includ-
ing humans, but the major incidence is in canines and
felines [1-3]. Mast cell tumors in the dog most commonly
develop in the skin. These tumors usually have a variable
appearance. In the predominant formation, the mast cell
looks similar to a normal cell and is relatively easy to
diagnose. Several approaches have been used to define
prognosis for mast cell tumors and for other types of ca-
nine and feline tumors. Clinical reports, surgical resec-
tion [1,4,5] and histological analyses of the tissue, as well
as assessment of kinetic parameters such as Ki-67 pro-
tein [6,7], BrdU [7], PCNA [8], AgNOR [9]-Argyrophilic
nucleolar organiser region, DNA ploidy[10], intratumoral
vascular density [11], p53 [12,13], c-KIT [14,15], nu-
clear morphometry [16], tumor profundity[17], and tu-
mor localization [18]. The most common method used
for determining the prognosis of a mast cell tumor is his-
tological gradation [19]. The histological evaluation is
also needed for the classification of the tumor and to ac-
cess surgical margins.
The diagnosis of mast cell tumors and other tumors
depends on the pathologist’s access to the material col-
lected from the surgeon. Most cancer diagnoses are de-
termined using cytological (fine need aspiration) and
histological (excisional biopsy) evaluations. Consequently,
mistakes in the pathological evaluation can lead to inap-
propriate treatment choices [20,21]. Several methods
exist for studying mistakes in anatomopathological evalu-
ation of the samples submitted for analysis. Sampling
mistakes are most commonly related to the preparation of
the samples (inappropriate storage of the samples, lack of
anatomical references for the fragments, and insufficient
samples from small tumors) [20-22].
The officially released percentage of error is known to
vary significantly, ranging from 1% to 43% (averaging
between 1% and 5%) in human medicine [22]. Failures
are known to originate from the surgeon or his/her team
upon transfer of the material for histopathology. In the
literature, no studies in human or veterinary medicine
have quantified the percentage of error in the histopa-
thological analysis that results from inappropriate prepa-
ration of the samples.
Excisional biopsy is used to provide useful informa-
tion and has diagnostic and prognostic roles in several
types of human and canine tumors.. Some care must be
*
Supported by Fundação de Amparo a Pesquisa do Estado de São
Paulo (FAPESP). Presented as an abstract at the 30th Annual Con-
ference of the Veterinary Cancer Society, San Diego—USA, 2010.
Copyright © 2012 SciRes. OJVM