the aim of this article is to emphasize on a rare occurrence with its clinicopathological features and differential diagnoses in view of the recent literature .
a 22 year - old woman presented with an acute onset of lower abdominal pain of 2 days duration . on bimanual pelvic examination , a right adnexal mass was palpated .
ultrasonography revealed a right ovarian solid mass measuring 4.5  cm    3.8  cm    3  cm with a low - resistant vascular flow pattern on doppler examination .
an adnexal mass , identified on ultra - sound , was explored through a lower midline incision which revealed a solid hemorrhagic mass in the right ovary .
macroscopically , the outer surface of the mass was smooth and glistening with a grayish white to purplish tint .
1 ) due to multioculated cystic spaces filled with frank blood . microscopically , most of the ovary was replaced by numerous dilated thin walled vascular channels , of variable size and configuration ( fig .
thrombi were noted but there was no necrosis . a follicle cyst and a corpus luteum were also present . the diagnosis of primary ovarian haemangioma , a benign vascular tumor was made .
immunohistochemistry , revealed cd 31 & cd 34 positivity of the cells lining the lumina , confirming their vascular nature ( fig .
haemangiomas are benign vascular tumors arising from failure in vascular formation , particularly in the canalizing process , forming abnormal vascular channels .
the difference between these two types relate to the size of the blood vessels formed .
vascular tumors of the female genital tract , especially those of the ovary , are very rare .
cyclic changes in the female genital organs during the reproductive period and the asymptomatic nature and small size of the neoplasm have been attributed to explain its rarity of occurrence .
although the exact number of ovarian haemangiomas is disputed , the number of well documented cases seems to be 50 or more but does not exceed 60 .
large lesions tend to present clinically as adnexal mass , frequently associated with lower abdominal pain , nausea and vomiting , due to torsion or abdominal distension because of the mass itself .
only a few of the ovarian haemangiomas have been reported to be associated with massive ascites and elevated serum ca-125 levels clinically mimicking an ovarian carcinoma .
preoperative doppler examination of such a lesion may show a low - resistant vascular flow pattern , supporting malignant neoplasia of the ovary .
pseudo - meigs syndrome , stromal luteinization , stromal hyperplasia , and thrombocytopenia have also been reported as complications of ovarian haemangioma .
the decreased platelet count is regarded as one of the manifestations of kasabach and merritt syndrome , particularly in bilateral cases associated with diffuse abdominopelvic haemangiomatosis .
coexistence of non - ovarian neoplasms such as endometrial carcinoma , cervical carcinoma , rectosigmoid carcinoma , and tubal carcinoma has also been reported .
although the etiology remains unknown , these lesions have been considered either hamartomatous malformations or true neoplasms in which pregnancy , other hormonal effects , or infection have been implicated as factors , enhancing the growth .
it has been suggested that the hyperestrogenism caused by pre - existing stromal luteinization of ovaries may stimulate the development of an ovarian haemangioma due to the growth stimulatory effects of estrogens on vessels and expression of estrogen receptors by haemangiomas .
according to another hypothesis , the presence of an expansile ovarian hemangioma induces stromal luteinization by mass effect .
these luteinized stromal cells produce androgens , which are subsequently converted to estrogens in adipose tissue , potentially causing unopposed estrogenic stimulation to the endometrium which may present as postmenopausal or dysfunctional uterine bleeding , aching breasts , advanced male type hair loss , and elevated androgen and estradiol levels .
macroscopically , ovarian haemangiomas are usually small with size ranging from 5  mm to 24  cm in its greatest diameter .
although they may be encountered in any part of the ovary , the medulla and hilum appear to be the most common sites .
histologically , they demonstrate either a cavernous , capillary , or mixed type with the cavernous type predominating , as in the present case , in contrast to haemangiomas in other parts of the body .
microscopically , they are composed of dilated , blood - filled , generally thin - walled vessels ranging from small to large size , lined by a single layer of flattened endothelial cells .
the vessels may be haphazardly located or display a roughly lobular arrangement in a variable amount of connective tissue stroma in which inflammation , hemorrhage and hemosiderin deposits , can be detected .
extensive punctate calcification in cavernous haemangioma was reported by kim et al.the present tumor was devoid of calcification probably because of early presentation and surgery . sometimes both preoperative findings and intra - operative structures can be confusing .
thus to avoid unnecessary radical surgery for a benign neoplasm , haemangioma should be kept in mind as a differential diagnosis of an ovarian mass before surgery .
while the clinical differential diagnoses of ovarian haemangiomas include tubo - ovarian mass , twisted ovarian cyst , and chocolate cyst , the main pathological differential diagnoses are those of vascular proliferations , lymphangioma , and monodermal teratoma composed of a prominent vascular component .
haemangioma in the ovary must be differentiated from proliferations of dilated blood vessels of the ovarian hilar region . to define the lesion as a true hemangioma
, a mass of vascular channels with minimal amounts of stroma should form a reasonably circumscribed lesion distinct from the remainder of the ovary .
one of the main characteristics of these vessels is that they may be calcified or have thickened walls and narrowed lumina due to medial deposition of a hyaline , amyloid - like material .
lymphangioma , which was considered in the differential diagnosis of this case because of a similar morphological appearance , was excluded due to the absence of pale eosinophilic homogeneous material within the vascular channels .
one of the controversial issues regarding the differential diagnosis involves distinguishing a monodermalteratoma having an angiomatous component from a pure haemangioma .
although vascular elements are not generally a component of ovarian teratomas , bilateral ovarian teratomas with a large hemangiomatosis component have been reported in which the lesions were distinguished from a pure hemangioma by the presence of a focus of respiratory epithelium .
haemangiomas of the ovary are very rare neoplasms with a wide age range and incidental discovery during operation or autopsy .
the risk of kasabach and merritt coagulopathy has to be considered in larger tumors , thus necessitating correct diagnosis and definitive surgical treatment .
there is no conflict of interest related to the work among the authors in this study.\
the source of funding was institutional funds of drs tribedi & roy diagnostics laboratory , kolkata .
written informed consent was obtained from the patient for publication of this case report and accompanying images .
bm , ss ; arq & sr performed the histological examination and prepared the manuscript .
arq & sr have supervised all the work and final correction of the manuscript done by them .
 introductionhaemangioma of ovary is a rare tumour.presentation of casewe report an ovarian haemangioma which presented as an acute abdomen due to an adnexal mass.discussionwe report an ovarian haemangioma which presented as an acute abdomen due to an adnexal mass . 
 haemangiomas have been reported in other organs but ovarian haemangioma is a rare tumor , usually asymptomatic and presenting as an incidental finding . 
 large lesions tend to present clinically with pain . 
 a few cases have been described in the literature.conclusionconsidering their rare occurrence such tumors are a diagnostic challenge . 
Introduction
Case report
Discussion
Conclusion
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