European Journal of Cardiovascular Medicine

Ovarian teratomas are tumors that comprise elements originating from all the three germ cell layers of the ovary. This group encompasses mature cystic teratomas (MCTs), immature teratomas and monodermal teratomas (e.g., struma ovarii, carcinoid tumors). MCT constitutes the most common ovarian germ cell tumor accounting for 10-20% of all the ovarian neoplasms [1]. They are mostly unilateral and appear between 20 to 40 years of age [1]. Grossly they are commonly cystic with a mean diameter of 5-10 cm containing pultaceous material, hair and components such as cartilage, teeth and bone and histologically include derivatives from two or three germ cell layers [2]. Complications routinely encountered with dermoid cysts are torsion, rupture and infection [1]. Teratomas are infrequently malignant and exhibit aggressive growth of one or more of the histological elements. Squamous-cell carcinoma is the most frequently reported malignancy [3]. Risk factors for malignant change must be dealt cautiously when the patient age is older than 45years, tumor size larger than10 cm, and quick growth [3]. The current review represents a retrospective analysis of morphological spectrum and complications associated with ovarian teratomas in our institution over two years duration.

It is a retrospective 2-year study of all ovarian teratomas reported from January 2021 to December 2023 in Department of Pathology, in a tertiary care hospital in Visakhapatnam. Ethical clearance was obtained to carry out the study. The study comprised 59 cases of ovarian teratomas throughout the course of these two years. The pathological records include data on age, laterality, size, gross appearance, microscopic features and complications.

Statistical analysis:

SPSS software version 22 was used to summarize and analyze the data. The results are shown as percentages and were obtained using frequency distribution.

380 ovarian neoplasms were submitted for histopathological examination in 2 years from 2021 to 2023, out of which 360 were benign and 20 malignant. The most common benign lesion diagnosed was benign serous cystadenoma followed by mucinous cystadenoma, mature cystic teratomas and endometriotic cysts. The malignant tumors included were serous papillary cystadenocarcinomas, mucinous cystadenocarcinomas, endometriotic carcinomas, yolk sac tumors, dysgerminomas, immature teratomas and teratomas with 

malignant transformation. 59 cases of ovarian teratomas were recovered in the current investigation which explained 15.5% of the total ovarian neoplasms out of the 59 cases, 53 cases were mature cystic teratoma, 1 case of immature teratoma, 2 cases of monodermal teratoma and 3 cases of teratoma with malignant change. The age distribution ranged from 18 to 65 years with median of 32 years. Majority of the cases (35%) were of 25 - 45 years and only 12% were greater than 50 years of age. The most frequent presenting complaint in this study was an abdominal lump followed by pain. Few cases were asymptomatic and incidentally diagnosed. Among the 59 ovarian teratomas, there were 32 cases (54.2%) that were right sided followed by 22 (37.2%) left sided and 5 (8.4%) bilateral cases. Tumor size was less than 10 cm diameter in 81.3 %, 11-20 cm in 15.2% cases and >20 cm in 3.3 % cases. On cut section 45 cases (76.3 %) were completely cystic and unilocular and 23.7 % cases were multilocular and showed solid component and hemorrhagic areas. The content of the cyst was predominantly pultaceous material and hair in 55 cases with teeth in 8, mucinous fluid in 4, serous fluid in 2 cases and hemorrhagic fluid in 2 cases [Table 1]. Sections from Rokitansky protruberance contained the largest number of diversified structures. The teeth found were mostly molars followed by incisors and were found lying free in the cyst cavity or implanted in the wall.

Histologically, 57 mature teratomas contained both ectodermal and mesodermal derivatives with 20 cases also containing endodermal derivatives. The derivatives of 

ectoderm included skin with appendages, keratin and nervous tissue. Mesodermal derivatives included blood vessels, fibroadipose tissue, smooth muscle, skeletal muscle, teeth, lymphatic tissue, cartilage and bone. Salivary gland acini, thyroid, respiratory and intestinal epithelium represented endodermal derivatives [Table 2]. Two cases of struma ovarii [Figure 1a] with thyroid tissue formed part of the present study. Stratified squamous epithelium could not be identified in these 2 cases and no tissue other than thyroid could be recognized. Keratinized stratified squamous epithelium with skin appendages is the most frequent component in benign cystic teratomas accounting for 96.6%, followed by fibroadipose tissue (89.8%). Hyaline cartilage was observed both with and without areas of calcification, and our study revealed its incidence to be 45.7 %.

Eight cases were complicated, which comprised 5 cases of torsion and 3 were of malignant transformation. Among five percent of mature cystic teratoma had malignant change with two cases of Squamous Cell Carcinoma [Figure 1b] and one case of endometrioid carcinoma [Figure 1c]. All the three teratomas with malignant change measured more than 10 cm and contained a solid component.

Coexistent findings were two cases of serous cystadenoma, four cases of mucinous cystadenoma, three cases of yolk sac tumor and two cases of dysgerminoma. 

Table 1 - Gross features of mature cystic teratoma

Table 2 - Microscopic features of mature cystic teratoma

The most frequent ovarian tumors are ovarian teratomas, which contain both mature and immature tissues due to their origin from one or more of the three major germ cell layers. According to the “missed target theory”, totipotent primordial germ cells lead to the development of teratomas. Around five weeks of conception the cells migrate from the endodermal cells of the yolk sac to the gonadal ridges. Ovarian teratomas may occur, if any of these cells fail to reach their aimed destination [5]. The aim of this study is to analyze the morphological spectrum and complications associated with ovarian teratomas.

In this study, the rate of occurrence of ovarian teratomas was 15.5% amongst ovarian tumors which were on par with the results of Ruchi et al [1] and mumtaz et al [2], while Ahmad et al [4] displayed a result of 35.17% of ovarian teratomas in their study. The age distribution ranged from 18 to 65 years with median of 32 years. Majority of the cases (35%) were of 25 - 45 years and only 12% were greater than 50 years of age. These results were in line with the Ruchi et al [1], mumtaz et al [2]  and Hursitoglu et al [6] study. Abdominal lump and pain are the most common presenting symptom as backed by the findings of Amit et al [5]. Out of the teratomas reported in this study, 37.3% occurred on the left side and 54.2% on the right side. The left laterality is more common according to Mumtaz et al [2] However, on the contrary, Ismail RS reported right sided distribution of 72.2% and 55.4% against our findings [7]. Bilaterality rather less common with a documentation of 8.2 to 16.7% [8,9]and this coincides with the present study.

In this study both gross and microscopic evaluation of mature ovarian teratomas was done. The gross examination size, laterality, number of locules and its contents were analyzed, whereas histologically the features of various mature tissues were evaluated.

The dimensions of the tumor in the present study were less than 10 cm diameter and predominantly unilocular in majority of the cases which correlated with the analysis by Outwater et al and Jung et al [10,11]. Grossly majority of teratomas were cystic and 23.7% cases showed a solid component along with cystic component which is in correlation with the study done by Morillo et al [12]. No solid teratomas were not encountered in the present study.

In the study of Caruso et al[13] , ectodermal, mesodermal and endodermal provenience were 99.1%, 45.3% and 39.6% each, where as in our study the distribution of the three   derivatives  were  96.6%,  84.7%  and  13.5% 

respectively. The most frequent ectodermal derivatives in the present study were skin and its appendages which is consistent with the findings of other studies [13].

The mesodermal origin was found predominantly as fibroadipose tissue and cartilage in 84.7% and 28.8% of cases which is in correlation with the study by Ong HC et al [14]. However, Sah et al [15] reported 19.1 % bone and 39 % cartilage respectively in their study. The endodermal components in our study corresponded with Mumtaz et al

[2] study, included glandular structures (35.5%), respiratory epithelium (13.5%), GIT epithelium (8.4%) and thyroid (11.8%). One case of immature teratoma was diagnosed in 40-year-old female, the ovarian mass was partly cystic and predominantly solid with variegated appearance. Microscopically composed of an undifferentiated stroma found in association with immature neural epithelium and cartilage. Adjacent areas of cartilage, fat, muscle and respiratory epithelium were found.

In the present study, most prevalent complication was torsion accounting for 8.4 % cases, which was in consistence with the other studies [6,9,16]. Three cases showed malignant change, two were squamous cell carcinoma [Figure1b] and one case of endometrioid carcinoma [Figure 1c] on mature cystic teratoma. In contrast to the other studies [6,16,17], the frequency of malignant change was marginally higher, at 5%. The three cases included in the present study were postmenopausal women and studies show that the average age at which malignant change occurs was 53.5 years [18]. In all the three cases the tumors have dominant cystic component with distinct solid area. Malignant change in a mature teratoma may be successive changes of metaplasia, atypical hyperplasia, carcinoma in situ and invasive carcinoma. The plausibility of malignant change in mature cystic teratoma can be speculated by factors such as age, large tumor size (> 15 cm) and solid component.

Mature cystic teratomas are the most common form of ovarian germ cell tumors and occur predominantly in reproductive age group. Torsion is the most frequently encountered complication. It is imperative to take into account the potential for malignant transformation, especially in patients who are elderly and have large tumors.

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