Utility of Image Guided Fine Needle Aspiration in the Diagnosis of Ovarian Masses: A Cytohistopathological Correlation

Background: The incidence of ovarian masses has increased over the past two decades and is one of the leading causes of cancer-related deaths globally. Although histopathology remains the gold standard, in recent times, imageguided aspiration is being increasingly used as a rapid, inexpensive and efficient method for the pre-operative diagnosis of ovarian masses. The present study was performed to evaluate the efficacy of image guided FNAC in diagnosis of ovarian masses in comparison with histopathology and to assess the limitations of cytological interpretation. Methods: The study was conducted on 92 cases of ovarian masses which were evaluated by image guided FNAC. Sensitivity, specificity and diagnostic accuracy were calculated using histopathology as gold standard. Results: Cytological diagnosis was obtained in all the 92 patients with ovarian masses followed by histopathological examination. The cytological diagnosis was grouped into 2 categoriesBenign/Possibly Benign (60 cases) and Malignant/Suspicious of malignancy (32 cases). On cytohistological correlation it was found that a correct diagnosis was made in 86 cases, resulting in a diagnostic accuracy of 93.4%, sensitivity of 84.3 % and specificity of 98.3%. Conclusion: Image guided FNAC seems to be a relatively safe, simple, fast and cost-effective procedure where most ovarian malignancies can be correctly diagnosed with a high accuracy. Original Article *Corresponding author: Dr. Menka Khanna, Department of Pathology, SGRDIMSAR, Amritsar, India Phone: +91 9464986355 Email: [email protected] A-504 Diagnosis of Ovarian Masses by Image Guided FNAC Annals of Pathology and Laboratory Medicine, Vol. 03, No. 06, (Suppl) December, 2016 Introduction Ovarian neoplasms are a heterogenous group comprising of benign and malignant tumors of epithelial, stromal and germ cell origin. [1] The incidence of malignant ovarian masses has increased over the past two decades and is one of the leading causes of cancer-related deaths globally. The majority of ovarian masses are benign but almost two-thirds of malignant ovarian tumours present at an advanced stage. [2] Fine-needle aspiration cytology (FNAC) of these ovarian masses is offer the potential to decrease the need for surgical procedures in these women. The use of radiological techniques can ensure greater accuracy and reduction in false negativity in the assessment of tumors by increasing the yield of cytological specimens. Differing from blind procedure, ultrasound or CT guided FNAC can localize the most suspicious areas in tumor mass and therefore help in taking the sample from the most representative site. [3,4,5] Geier and Strecker have suggested that FNAC should be used for (1) recurrent and metastatic tumors, (2) suspected benign ovarian cysts and (3) when the patient›s condition is unsuitable for laprotomy. [6] However, till today, gynaecologists all over the world are hesitant to accept the role of FNAC on pelvic masses because of the controversial opinion about the potential risk of intraperitoneal tumor implantation, particularly of ovarian tumors, although the risk of carcinoma cell seeding within the abdominal cavity due to contamination by needles is overestimated and has not been documented. [7] Although histopathology remains the gold standard, in recent times, image-guided aspiration is being increasingly used as a rapid, inexpensive and efficient method for the pre-operative diagnosis of ovarian masses.[8 ]The present study was performed to evaluate the role of image guided FNAC in pre-operative cytological diagnosis of ovarian masses in comparison with histopathology and to assess the discrepancies and limitations of cytological diagnoses. Materials and Methods The study was conducted on 92 patients who presented with the ovarian masses diagnosed clinically or radiologically. Following the clinical examination, informed consent was taken from the patients. USG/CT guided FNAC was done using 22-23 gauge needle attached to a 20 ml syringe. Smears were prepared from the aspirate, fixed in 95% alcohol and stained with May Grumwald Giemsa and Hematoxylin and eosin stains. In the cases where cyst fluid was aspirated, it was subjected to cytocentrifugation and the sediment was stained by the similar methods. No major complications were observed in any of the patients. The cytological diagnosis was compared with histological diagnosis. Taking histological diagnosis as the gold standard, various statistical calculations were done. Result A total of 92 cases of ovarian mass lesions were evaluated on cytological smears. The most common presenting feature was lower abdominal pain (80.5%), followed by abdominal distension (50%), menstrual irregularity (27.7%) and weight loss (8.3%). The age of the patients range from 18 to 65 years, with maximum patients in 4th decade of life. USG / CT helped in the assessment of type of mass lesion (cystic/solid) along with its size, location and extent and thus augmented the cytological diagnosis. The cytological diagnoses were made as benign/possibly benign and malignant/suspicious of malignancy. Considering the histopathological diagnosis as gold standard, the cyto-histopathological correlation was done in these cases. On histopathology 60 cases were diagnosed as non malignant, out of which 8 cases were of non-neoplastic cysts and 52 cases were of benign ovarian tumors. Serous cystadenomas were the most common (27) benign ovarian tumor followed by mucinous cystadenoma (14) , mature teratoma (8) and fibroma (2).There was one case each of thecoma and sclerosing stromal tumor.( Table 1). A histopathological diagnosis of malignancy was given in 32 cases. Serous cystadenocarcinoma was the most common (16) histopathology diagnosis among malignant lesions followed by mucinous cystadenocarcinomas (5) and serous borderline tumor (3). There were 2 cases each of mucinous borderline tumor, dysgerminoma and granulosa cell tomor and one case each of immature teratoma and mixed germ cell tumor. (Table 2) Mature teratomas on histopathology show cyst lined by keratinising stratified squamous epithelium along with differentiated glandular epithelium,neuroglia and other elements.(Figure 1) However in immature teratoma islands of neuroepithelium were clearly identified. The sections in cystadenomas showed cysts lined by single layer of columnar epithelium which was ciliated in serous tumors, where as in borderline cases complex papillary structures lined by epithelium with stratification and nuclear atypia were seen; clear cut stromal invasion was identified in cystadenocarcinomas. (Figure 2) Sclerosing stromal tumor showed lobular arrangement with alternate hyper and hypocellular areas comprised of oval to spindle shaped cells with many dilated blood vessels in hypocellular areas. The sections in granulosa cell tumor showed sheets of oval to spindle cells with nuclear grooves and forming Call Exner bodies. (Figure3) FNAC from serous cystadenoma mostly yielded straw coloured fluid and the smears prepared