Sabato 27 ottobre 2012 - Pacini Editore

304
GEnITALE MASCHILE E FEMMInILE
Myxoid leiomyosarcoma of the uterus
A. Barone1 , M.R. Ambrosio1 , B.J. Rocca1 , M.A.G.M. Butorano1 ,
M.G. Mastrogiulio1 , A. Ambrosio2 , S. Mannucci1 , R. Santopietro1 1 Department of Human Pathology and Oncology, Pathological Anatomy
Section, University of Siena, Italy; 2 University “Magna Graecia” of Catanzaro,
Italy
Background. Uterine sarcomas are rare tumours that account for
only 3% of all uterine neoplasms and less than 1% of all female
genital tract cancers. The three most common types of uterine
sarcomas are malignant mixed mesoderm sarcomas, leiomyosarcomas,
and endometrial stromal sarcomas. One third of uterine
sarcomas are leiomyosarcomas, of which myxoid leiomyosarcomas
(MLMS) are an extremely rare variant which is a diagnostic
challenge, because of the relatively bland appearance of the cells
and the hypocellular nature of the proliferation. Infact, the usual
diagnostic criteria for classification of uterine smooth muscle
tumours, such as prominent nuclear pleiomorphism and high mitotic
index (> 10 mitotic figures per 10 high-power fields-HPF),
are often absent, and the presence of tumour cell necrosis is quite
difficult to ascertain in myxoid leiomyosarcomas. The presence
of two of these findings is sufficient for diagnosis of typical
leyiomiosarcoma, but not for its epithelioid and myxoid variants.
Only 30 cases of MLMS have been reported to date. We describe
a further case.
Materials and methods. A 66-year-old woman who reached
the menopausal status 15 years ago, presented to the Gynaecologic
Unit of Siena University Hospital with a 4-month history
of progressive abdominal enlargement, dyspepsia, abdominal
pain and uterine bleeding. Thirty years before, the patient had
undergone right ovariectomy for cystic endometriosis. At pelvic
examination, a massive, ill-defined, symmetric, soft and slightly
tender mass was detected extending from the lower abdomen to
the xiphoid. The uterus and left adnexa were not palpable. Ultrasonography
(US) and computer tomography revealed an enlarged
uterus with a huge abdominal mass and a hypoechoic lesion of
40 mm of the left ovary. Laboratory values were within reference
range. The clinical diagnosis was uterine leiomyoma. The patient
underwent total hysterectomy, left salpingo-oophorectomy and
right ooforectomy. Surgical specimens were formalin-fixed and
paraffin embedded. From each block, 4-µm thick sections were
obtained for histology and immunohistochemistry. The following
antibodies were checked: Cytocheratin AE1/AE3, EMA, Vimentin,
Desmin, Caldesmon, Smooth Muscle Actin (SMA), Estrogen
and Progesterone receptors, Ki-67.
Results. Macroscopically, the uterus was deformed by a huge
mass growing from the fundus, infiltrating the miometrium
and the serous covering; the mass measured 11.5x7x3cm and
was gelatinous. The cut surface was variegated, ranging from
brownish to amber yellow. Only small solid areas were present.
Microscopically, the tumor was strikingly myxomatous, with
large necrotic and hemorrhagic areas. Spindle-shaped cells were
seen in the copious mucoid matrix, showing nuclear atypia and
cellular pleomorphic areas. The tumor invaded endothelium-lined
vascular spaces; the infiltrating borders were jagged and irregular
with projections into the myometrium. The mitotic count was 20
mitoses per 10 HPFs. The tumor invaded surrounding tissues and
the uterine cervix. Immunohistochemically the neoplasm was
positive for antibodies against SMA, EMA, Vimentin, and Cal-
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desmon. Desmin as well as Progesterone and Estrogen receptors
were negative. Proliferative index (Ki-67) was about 80%. On the
basis of these features, a diagnosis of myxoid leiomyosarcoma
was made.
Conclusions. Myxoid leiomyosarcoma of the uterus is an
extremely uncommon and aggressive neoplasm, with a poor
prognosis despite its bland cytology and histology. It presents
problems in diagnosis and management to be faced by pathologists,
gynaecologists and oncologists. It may show little atypia,
well-circumscribed borders, absence of necrosis and relatively
low mitotic index which are opposite findings to those characterizing
the usual uterine leiomyosarcomas. On the contrary, when
MLMS present infiltrating borders and vascular invasion, as in
our case, it has to be considered a variant with aggressive behaviour.
Myxoid inflammatory myofibroblastic tumours (IMTs) are
the most important lesions to exclude in the differential diagnosis.
IMTs, which rarely occur in the uterus, may display significant
myxoid change and increased mitotic activity. The relatively
young age of many patients with IMT, the presence of an inflammatory
(lymphoplasmacytic) infiltrate and immunoreactivity
with ALK1 are useful in distinguishing this entity from myxoid
leiomyosarcoma. An oedematous, hydropic change that develops
in some leiomyomas could be confused with myxoid change,
particularly when it is found in large areas. Hydropic change is
patchy and appears eosinophilic, in contrast to the basophilic appearance
of the myxoid areas in myxoid leiomyosarcomas. Also
endometrial stromal tumours may be characterized by myxoid
changes. However, typical endometrial stromal cells and prominent
vascularity are evident somewhere in the lesion. A positive
immunostain for CD 10 confirms the diagnosis of endometrial
stromal tumour. Surgery remains the appropriate treatment. However,
in spite of an aggressive surgical approach and local and
systemic control, recurrences and metastasis are frequent.
references
Burch DM, Tavassoli FA. Myxoid leiomyosarcoma of the uterus. Histopathology
2011;59:1144-55.
Toki N, Kashimura M, Hasegawa T, et al. Acta Cytologica 2000;44:415-9.
Vigone A, Giana M, Surico D, et al. Massive myxoid leiomyosarcoma of
the uterus. Int J Gynecol Cancer 2005;15:564-7.
Leiomyomatosis peritonealis disseminata:
report of a case
A. Barone1 , M.R. Ambrosio1 , B.J. Rocca1 , M.A-G.M. Butorano1 ,
A. Ambrosio2 , M.G. Mastrogiulio1 , L. Barbagli1 , R. Santopietro1 1 Department of Human Pathology and Oncology, Pathological Anatomy
Section, University of Siena, Italy; 2 University “Magna Graecia” of Catanzaro,
Italy
Background. Leiomyomatosis peritonealis disseminata (LPD)
is a rare benign disease of unknown etiology of women in the
reproductive age. It is characterized by multiple smooth muscle
tumors of varying sizes on the omentum and peritoneal surfaces.
A possible origin from submesothelial multipotential cells has
been suggested, although it is not clear if the stimulus to smooth
cell differentiation is hormonal, genetic or combined hormonal
and genetic. The condition is associated with high levels of exogenous
and endogenous female gonadal steroids (e.g. pregnancy,
prolonged exposure to oral contraceptives and/or combined hormonal
replacement therapy, granulosa cell tumours of the ovary),
indicating that oestrogens and progestins play an important role
in the pathogenesis of LPD as they do in leiomyomata uteri. Most
LPD cases are clinically benign, but in some instances they may