Sabato 27 ottobre 2012 - Pacini Editore

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Methods. In this study we examined a series of 192 colorectal
carcinomas surgically resected from January 2003 to
June 2010. Histological evaluation was done using standard
histologic sections stained with hematoxylin and eosin. The
tumors were widely sampled, with a number of tissue blocks
of approximately one per cm in largest tumor diameter. A
carcinoma was classified as micropapillary when micropapillary
tufts lacking true fibrovascular cores and surrounded by
empty lacunar spaces represented at least 5% of the tumor area
in histologic sections.
Results. 29 of the 192 tumors (15.1%) were classified as MPC.
In most cases the MP component represented < 30% of the
tumor volume. MP carcinomas were observed more often in
males than females (19.8% vs. 8.6%, P = 0.04). In contrast patient’s
age was not significantly related with the presence of MP
features. A highly significant relationship was evident between
MP component and tumor site. A MP component was present
in 27.9% of tumors located in the rectum, in 20% of tumors of
the left colon (descending and sigmoid colon) and in 7.1% of
tumors arising in the proximal colon (right and transverse colon)
(P = 0.003). MPCs were more often in advanced stages (III
and IV) compared to conventional adenocarcinomas (72.4% vs.
34.4%, P < 0.001). In addition, MPCs showed a more advanced
pT category (P = 0.03), more frequent involvement of the serosa
(41.4% vs. 21.5%, P = 0.03) and a much greater propensity
to lymph node metastasis (69.0% vs. 31.9%, P < 0.001) than
conventional adenocarcinomas. 48.3% of MPCs showed 4 or
more lymph node metastases, while only 15.3% of common
adenocarcinomas were classified as pN2. The frequency of distant
metastases at diagnosis was higher in the MPCs (17.2% vs.
9.8%), but the difference did not reach statistical significance.
Tumors with a MP component also showed more frequently
an infiltrative pattern of growth (47.4% vs. 13.8%, P = 0.002)
and extramural venous invasion (37.9% vs. 16.6%, P = 0.01).
Finally in our study 24 of the 29 MPCs (82.8%) were classified
as poorly differentiated (high grade), while only 22.1% of conventional
carcinomas were high grade (P < 0.001).
Conclusions. The results we obtained confirm the characteristics
of pathological aggressiveness of the MPCs reported in
literature and highlight the high propensity to lymph node metastasis
of these tumors. The prognostic significance of the MP
histotype has been evaluated only in a limited number of studies.
Given the association between MP component and lymph
node metastasis, distant metastasis and other pathological
parameters of aggressiveness, it is expected that this histological
type is characterized by a generally poor prognosis, with
survival rates lower than those observed in common adenocarcinomas
and mucinous adenocarcinomas. Further studies
are certainly necessary to verify if the MP histology represents
a prognostic factor more important and reproducible than the
degree of differentiation and to define the biomolecular and
genetic basis of this tumour type.
references
1 Verdù M, et al. Clinicopathological and molecular characterization of
colorectal micropapillary carcinoma. Mod Pathol 2011;24:729-38.
2 Xu F, et al. Micropapillary component in colorectal carcinoma is
associated with lymph node metastasis in T1 and T2 stages and
decreased survival time in TNM stages I and II. Am J Surg Pathol
2009;33:1287-92.
3 Kim M-J, et al. Invasive colorectal micropapillary carcinoma: an
aggressive variant of adenocarcinoma. Hum Pathol 2006;37:809-15.
4 Haupt B, et al. Colorectal adenocarcinoma with micropapillary
pattern and its association with lymph node metastasis. Mod Pathol
2007;20:729-33.
Sakamoto K. Primary invasive micropapilklary carcinoma of the colon.
Histopathology 2005;47:479-84.
CONGRESSO aNNualE di aNatOmia patOlOGiCa SiapEC – iap • fiRENzE, 25-27 OttOBRE 2012
Usefulness of anti-TCrGD antibody in gluten
sensitivity diagnosis on formalin-fixed paraffinembedded
biopsies
S. Lonardi1 , V. Villanacci1 , A. Lanzini2 , F. Lanzarotto2 , L. Lorenzi1
, U. Volta3 , F. Facchetti1 1 2 Department of Pathology, Gastroenterology Unit, Spedali Civili-University
of Brescia, 3 Department of Clinical Medicine, St Orsola-Malpighi
Hospital-University of Bologna, Bologna, Italy
Introduction. Small bowel intraepithelial lymphocytosis (IL) may
depend from different causes, including Gluten Sensitive Enteropathy
(GSE). 1 Demonstration of increased number of duodenal
T-cell receptor gamma-delta (TCRGD) positive intraepithelial
lymphocytes (IELs) has been used to support GSE diagnosis on
frozen material. 2-3 We have evaluated an anti-TCRGD antibody on
formalin-fixed paraffin embedded (FFPE) small bowel biopsies.
Material and methods. Anti-CD3 (clone SP7, 1:100) and anti-
TCRGD (TCR CgM1, clone g3.20, 1:400) from Thermo Scientific,
Fremont, CA) were applied by immunohistochemistry on 59 FFPE
biopsies from 18 cases of celiac disease (CD) with mild/severe atrophy,
19 cases of IL in CD patients on Gluten Free Diet (IL-GFD),
14 cases of IL (6/14 with abnormal serology for GSE), and 8 controls
(CTR) with mild duodenitis and negative CD serology and genotyping.
Sections were digitalized with Aperio Scanscope (Nikon)
and IELs/100 epithelial cells (EC) were counted in six high power
fields. For statistic analysis the Mann-Whitney test was applied.
Results. CD3+ IELs were significantly higher in CD (mean±SD
52.0±15.3) (Figure 1A), IL-GFD (43.6±18.3) and IL (46.3±16.6)
(Figure 2A) compared to CTR (24.1±7.6) (p = 0.0004, p = 0.0019
and p = 0.0006, respectively) (Figure 3A)
Fig. 1. immunohistochemistry for Cd3 (a) and tCRGd (B) in Cd; original
magnification: 200x.
Fig. 2. immunohistochemistry for Cd3 (a) and tCRGd (B) in il with
abnormal serology; original magnification: 200x.
Fig. 3. Cd3+ and tCRGd+cells/100 EC in Cd, il-Gfd, il were significantly
different compared to CtR (a-B). p-value in a: * Cd vs CtR p = 0.0004,
** il-Gfd vs CtR p = 0.0019, *** il vs CtR p = 0.0006. p-value in B: * Cd
vs CtR p < 0.0001, ** il-Gfd vs CtR p = 0.0004, *** il vs CtR p = 0.0046.