Sabato 27 ottobre 2012 - Pacini Editore

COmuNiCaziONi ORali
and hindgut origin: tumor-node-metastasis classification determines
clinical outcome. Cancer 2011;117:3332-41.
9 Couvelard A, Deschamps L, Ravaud P, et al. Heterogeneity of tumor
prognostic markers: a reproducibility study applied to liver metastases
of pancreatic endocrine tumors. Mod Pathol 2009;22:273-81.
Immunocytochemistry and BrAF mutation analysis
in thyroid lesions suspicious for malignancy
diagnosed on liquid- based cytology.
A new challenge
E.D. Rossi, M. Martini, P. Straccia, S. Capodimonti, T. Cenci,
C.P. Lombardi1 , A. Pontecorvi2 , L.M. Larocca, G. Fadda
Division of Anatomic Pathology and Histology 1 Division of Endocrine
Surgery, 2 Division of Endocrinology- Università Cattolica del Sacro Cuore,
“Agostino Gemelli” School of Medicine, Rome
Introduction. Follicular patterned lesions are a common finding
in general population for which a preoperative cytological diagnosis
in order to define a correct therapeutical management, is
crucial. Approximately 65-70% of fine needle cytologic biopsies
(FNC) are classified as benign as well as 5-10% are diagnosed
as malignant. The remaining 25-30% are included in the grey
zone of the indeterminate diagnoses where benign neoplasms
cannot be cytologically distinguished by the malignant ones. The
Suspicious for Malignancy (SM) category represents a cytologic
category in which the morphology alone is not able to define
conclusively the malignant nature of a defined lesion. The aim of
this study is the evaluation of the role of simultaneous analyses of
immunocytochemistry and BRAF mutation in predicting the outcome
of SM thyroid follicular lesions diagnosed on liquid based
cytology (LBC), and, hence, in adding further diagnostic details
which could guide a better clinical management. Immunocytochemistry
based on the use of an immunopanel (e.g. HBME-1
and Galectin 3) has shown a significant role in a better definition
of low and high risk follicular neoplasms. Activating mutations
in the V600E locus of BRAF-1 gene have been identified in about
29-69% of PTC and more than 80% of the tall cell variant (TCV)
whereas they have not been detected in benign lesions and in the
majority (80%) of the follicular variants of PTC (FVPC).
Materials and methods. From October 2010 through June 2011,
43 SM, processed by liquid based cytology (LBC), were studied
for the application of an immunopanel made up of HBME-1 and
Galectin- 3 and for the BRAF mutational analysis. The aspirated
material was processed with the ThinPrep 2000 technique (Hologic
Co, Marlborough MA). Immunocytochemistry, carried out
with the ABC peroxidase method and BRAF mutation analysis,
using the direct sequencing method, were performed on the residual
cells stored in the PreservCyt solution.
Results. Thirty one cases out of 43 (73%) underwent surgery and
were diagnosed respectively as: 5 benign lesions (BL, including
Follicular Adenoma), 17 papillary carcinomas, (PTC), 7 follicular
variants of papillary carcinoma (FVPC) and 2 tall cell variants
of PC (TCV). All BL resulted negative for the immunopanel
while all the malignant lesions resulted positive. All 12 cases that
expressed the BRAF mutation (39%) resulted histologically malignant
whereas all BL expressed BRAF wild type. A significant
association between BRAF mutation and cancer multifocality
was found (p < 0.0001, Odd Ratio, OR 0.003). The presence
of BRAF mutation was also significantly associated with nodal
involvement (p < 0.0001, OR 0.0061) and extracapsular invasion
(p = 0.0001, OR 0.011). A significant association between the
positive ICC panel and the malignant nature of the tumors was
assessed (p = 0.0007 OR 55).
Conclusions. Immunocytochemistry and BRAF gene mutation
analysis can be successfully carried out on LBC-processed material.
The simultaneous application of the two techniques on preoperative
cytology may help in identifying up of 39% carcinomas
among the category of SM supporting a more aggressive surgical
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decision. In this group a significant correlation with nodal involvement
and multifocality highlights the role of BRAF analysis
in discriminating tumours with a more aggressive behaviour from
those pursuing a favourable clinical course.
references
1 Rossi ED, et al. Cancer Cytopathol 2005;105:87-95.
2 Nikiforova MN, et al. Thyroid 2009;19:1351-61.
3 Nikiforov YE, et al. J.Clin Endocrinol Metab 2009;94:2092.
4 Fadda G, et al. Eur J Endocrinol 2011;165:447-53.
A case of hyalinizing trabecular tumor (HTT) of the
thyroid gland in patient with multinodular goiter
G. Crisman1 , A. Marinucci1 , A.R. Vitale2 , T. Curti2 , V. Ciuffetelli3
, S. Saltarelli3 , G. Calvisi3 , G. Coletti3 , P. Leocata1 1 Anatomia Patologica, Dipartimento di Scienze della Salute, Università
dell’Aquila, L’Aquila, Italia; 2 U.O.C. Anatomia Patologica, P.O. “SS
Filippo e Nicola”, Avezzano (AQ), Italia; 3 U.O.C. Anatomia Patologica
Ospedale Civile “San Salvatore”, L’Aquila, Italia
Background. First described by Carney in 1967, Hyalinizing
Trabecular Tumor (HTT) represents a rare neoplasm. This lesion
has been defined by the WHO Classification of Tumors
of Endocrine Organs as “a rare tumor of follicular cell origin
with a trabecular pattern of growth and marked intratrabecular
hyalinization”.
HTT is of follicular derivation with a characteristic architectural
and histological features, which can mimic that of a Meduallry
Carcinoma or of a Papillary Carcinoma of the thyroid.
Material and methods. We report on a case of a 58-year-old
presented with a thyroid hypercaptant area in a scintigraphic
evaluation performed as a follow-up evaluation for a previous
bladder carcinoma. An ultrasonographic examination of her thyroid
gland revealed the presence of a single, capsulated nodule
of 25 x 13 x 20 mm in-dimension sited in the left thyroid lobe.
The remaining glandular area showed multiple colloidal nodules,
varying in shape and size, compatible with a diagnosis of multinodular
goiter. No regional lymphadenopathy has been detected
and Fine-Needle Aspiration Cytology (FNAC) as been performed
for diagnostic purpose. Cytological examination revealed several
tireocytes, mainly palced in aggregates, presenting mild to moderate
nuclear atypia and pseudoinclusions. On the basis of these
cytologic findings, a Papillary Thy roid Carcinoma (PTC) was
suspected and patient underwent total thyroidectomy.
Reslts. Grossly, a capsulated, whitish nodule of 1,8 cm indiameter
of the left thyroid lobe was detected. Histopathological
features revealed a lesion mainly composed by oval-shaped
tireocytes with irregular nuclei and nuclear grooves and pseudoinclusions,
within a prominent hyalinizing trabecular pattern.
The remaining thyroid gland consisted of numerous moderately
sized thyroid follicles and some lymphoid follicles with germinal
centers. The tumor cells exhibited a positivity for Cytokeratin
AE1/AE3 and Tireoglobulin and a negativity for Galectin 3,
Fig. 1. Histological features of the lesion. a: well-circumscribed nodule
within the left lobe (H&E, 2x magnification). B: trabecular growth
pattern with inter and intratrabecular.hyaline deposition (H&E, 10x
magnification).