Sabato 27 ottobre 2012 - Pacini Editore

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monolayered sheets of cells with dense cytoplasm and pale
nuclei, macrophages and debris. Some cells showed atypia and
intranuclear vacuoles, These findings were consistent with papillary
thyroid carcinoma. FNAC of the masseter muscle showed,
instead, pleomorphic discohesive cells. They had a high nuclear/
cytoplasmic ratio. The nuclei were hyperchromatic and characteristically
showed large nucleoli. Brown to green melanin
pigment was also found. These findings were consistent with a
metastatic melanoma and the diagnosis was then confirmed by
immunocytochemical stainings for S100 and HMB45, which
were positive. The patient underwent dermatologic visit examination,
which revealed on the skin of the left leg a 1,8 cm sized,
black-colored nodule with irregular borders. The histological
finding of the skin biopsy revealed a T3bN0Mx, Stage IIB
(TNM7) malignant melanoma. A whole body PET-TC showed
metastatic lesions in the lungs. BRAF mutation was investigated
and discovered by both direct sequencing and mutant
allele-specific PCR amplification for the T to A substitution at
nucleotide 1799 (V600E).
Conclusions. Several recent studies have reported the association
between malignant melanoma and thyroid cancer. The mechanism
for this is unclear. Some authors have reported that TSH
is more likely to be expressed by dysplastic nevi than by benign
nevi, and the dysplastic nevi of melanoma patients have a higher
TSH expression than that of healthy individuals. Thus, TSH has
been implicated in the malignant transformation of melanocytes
to melanoma, and TSH stimulates the growth of melanoma cells.
On the other hand, it has been suggested that melanoma might induce
the thyroid dysfunction and this might lead to hypothyroidism
under the condition of low circulating thyroid hormone levels
and concomitantly elevated TSH levels, although an autoimmune
mechanism has also been suggested. Moreover, the rearrangement
of RET and the mutation of BRAF, which are known to be
the causes of papillary thyroid carcinoma, are observed in cutaneous
malignant melanoma. It seems that BRAF plays a key role
in the development of these two kinds of tumors. As the patients
with papillary thyroid carcinoma have a higher risk of malignant
melanoma and vice versa, continuous monitoring in these two
categories is required.
references
Chi Yeon Kim, Seung Hun Lee, Chee Won Oh. Cutaneous Malignant
Melanoma Associated with Papillary Thyroid Cancer. Ann Dermatol
2010;22:370-2.
Ellerhorst JA, Naderi AA, Johnson MK, et al. Expression of thyrotropinreleasing
hormone by human melanoma and nevi. Clin Cancer
Res 2004;10:5531-6.
Ellerhorst JA, Sendi-Naderi A, Johnson MK, et al. Human melanoma cells
express functional receptors for thyroid-stimulating hormone. Endocr
Relat Cancer 2006;13:1269-77.
CONGRESSO aNNualE di aNatOmia patOlOGiCa SiapEC – iap • fiRENzE, 25-27 OttOBRE 2012
Goggins W, Daniels GH, Tsao H. Elevation of thyroid cancer risk among
cutaneous melanoma survivors. Int J Cancer 2006;118:185-8.
Shah M, Orengo IF, Rosen T. High prevalence of hypothyroidism in male
patients with cutaneous melanoma. Dermatol Online J 2006;12:1.
Soares P, Trovisco V, Rocha AS, et al. BRAF mutations and RET/PTC
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nasosinusal melanoma a rare (?) disease and
potential diagnostic pitfall. 12 years of experience
V.G. Vellone1 , E. Marrucci1 , F. Bussu2 , M. Rigante2 , C. Parrilla2 ,
G. Paludetti2 , E.D. Rossi1 , G. Fadda1 , G. Rindi1 , G.F. Zannoni1 1 Istituto di Anatomia ed Istologia Patologica-Policlinico A. Gemelli, Università
Cattolica S. Cuore, Roma; 2 Istituto di Clinica Otorinolaringoiatrica-
Policlinico A. Gemelli, Università Cattolica S. Cuore, Roma
Background. Nasosinusal Melanoma represents almost 1% of all
melanoma. As melanomas arising in other sites they can have a
protean appearance often resulting in inaccurate diagnoses with
worrisome consequences in prognosis and treatment planning.
Materials and methods. The computerized archive of the Surgical
Pathology Service of Policlinico A. Gemelli (Rome) was
retrospectively reviewed for the period 2000-2012. We found 13
cases. In all the cases all the submitted material was included in
paraffin; from each block two 3 µm thick histological slides was
cut at different levels and routinely stained in hematoxylin eosin.
Additional slides from the most significant specimen were cut
and submitted for immunohistochemistry.
Results. The mean age of the was 71,5 ± 10,4 years. 4 patients
were male; 9 patient were female. In most cases the disease manifested
as large, bleeding polypoid mass resulting in 2-12 paraffin
blocks.In most of the patients (7 cases) 3 anatomic sites were
involved; in 3 cases two anatomic sites were involved, in the remaining
3 cases one anatomic site was involved. The histological
slides revealed a poorly differentiated epithelioid neoplasm often
with dischoesive features in 9 cases, the remaining 4 cases were
mixed neoplasm with epithelioid and spindle cells. Brown, intracellular
pigment suggestive for melanin was present in 5. cases,
necrosis was evident in 4 cases. The immunohistochemistry examination
revealed positivity for Melan A in 13/13 cases; HMB
45 in 11/11; for S100 in 12/13 cases, Vimentin in 7/7; MITF in
3/3; Tyrosinase in 1/3. None of the cases showed positivity for
AE1/AE3, Cromogranin, Synaptofisin or LCA,
Conclusions. Nasosinusinusal melanomas are not so rare in diagnostic
routine. They can be mistaken for different neoplasms
of epithelial, mesechimal or lymphoid origin representing a
potential diagnostic pitfall. An accurate histological exam with
an extensive immunohistochemistry panel is required for a final
correct diagnosis, in particular in the amelanotic cases.