Diagnostic Pathology: Open Access
Open Access

Mature cystic teratoma is a common ovarian tumor accounting for 30%-45% cases [1]. The incidence of malignant transformation of mature cystic teratoma is 2% [2]. There may be malignant transformation includes squamous cell carcinoma, adenocarcinoma, melanoma, neuroendocrine tumor etc. in the setting of mature cystic teratoma. This malignant transformation is accompanied by complex chromosomal aberrations [3]. It is most commonly seen in postmenopausal women [4]. Although it carries poor prognosis there are no definitive clinical features, tumor markers and imaging methods making its preoperative diagnosis difficult. Most of the cases are thus diagnosed postoperatively [5]. We are presenting two cases of squamous cell carcinoma arising in mature cystic teratoma in postmenopausal women diagnosed postoperatively on histopathologic examination.

First case

A postmenopausal woman of age 47 years was presented to gynecological OPD with the complaints of pain lower abdomen for past 1 month. On clinical examination adnexal mass was felt on left side. Routine and specific examinations were carried out. On CECT, a cystic mass of size (13.8 × 11 × 9.8) cm suggestive of mature cystic teratoma was given as the diagnosis. TAH with BSO was done. Intraoperative findings showed left ovarian cyst with smooth external surface. The capsule was intact and no adhesions were present. Cut section showed-multiloculated cyst containing sebaceous material, hair and solid and papillary areas and diagnosis of Malignant ovarian tumor was suggested. Other structures were grossly unremarkable. The histopathologic examination confirmed the malignant nature of the cyst and diagnosis of squamous cell carcinoma arising in setting of mature cystic teratoma was given as shown in Figure 1.

Figure 1: Squamous cell carcinoma with adipose tissue in the ovary.

Second case

A woman of age 62 years was presented with the complaints of distension of abdomen from past 4-5 weeks. A mass of 24 weeks was felt. Routine and specific examinations were carried out. PAP smears showed inflammatory atrophic smear. On USG, diagnosis was solid cystic mass Dermoid Malignant tumor of size (17 × 16 × 12) cm was given with the advice of MRI for further characterization. TAH with BSO was done. The intraoperative findings showed left ovarian cyst with dense adhesion on posterior aspect and omentum. Cut section showed cyst containing sebaceous material and hair. The histopathologic examination of the sample was carried out and diagnosis of squamous cell carcinoma arising in the mature cystic teratoma was given as shown in Figures 2 and 3.

Figure 2: Squamous cell carcinoma along with epidermis.

Figure 3: High 40X view of squamous cell carcinoma.

Mature cystic teratoma is common ovarian tumor among young patients. It is also known as dermoid cyst. It is a germ cell tumor. Squamous cell carcinoma arising in mature cystic teratoma is extremely rare [6]. Other malignant transformations include adenocarcinoma and carcinoid tumors [7] can evolve from any germ layer [8]. It carries poor prognosis especially when diagnosed in advanced stage. Chemotherapy is required along with the surgery. Its preoperative diagnosis is difficult. Clinical features, tumor markers, CECT and MRI are not definitive for diagnosis. The diagnosis can be confirmed only on histopathologic examination. The malignancy can be suspected when mature cystic teratoma is arising in postmenopausal women [7,8]. The size of the cyst is larger than 9.9 cm [9]. Cut section of the cyst shows solid and cystic areas. The adhesions are seen during surgery. These features can be considered as risk factors for the malignant transformation. Takagi et al. have studied tumor markers and found CEA to be more useful than CA 125 and CA19-9 in malignant transformations [6].

The two cases presented here were also from postmenopausal age. The size of the cysts was greater than 9.9 cm. One of the case showed solid cystic areas while other showed adhesions with the posterior wall and omentum. The tumor marker can suggest the malignant transformation of mature cystic teratoma.

Although mature cystic teratoma is common but its malignant transformation into Squamous cell carcinoma, adenocarcinoma is extremely rare. It carries poor prognosis and need chemotherapy along with surgery. It has to be diagnosed early. Its preoperative diagnosis is difficult and can be confirmed on histopathology only so clinicians, radiologist and pathologist should be well aware of this entity.

There was no conflict of interest between the authors.