BACKGROUND: Mature cystic teratoma of the ovary is classified among the benign ovarian germ cell neoplasms, and its malignant transformation occurs very rarely (in about 2%). As a result of nonspecific signs and symptoms, preoperative diagnosis of theses malignancies is a challenge to clinicians, resulting in delayed diagnosis (in advanced stages) and poor outcomes.
METHODS: We report the case of a 43-year-old Iranian woman with progressive distension of the abdomen and hypogastric pain, who was diagnosed with squamous cell carcinoma transformation in a mature cystic teratoma of the ovary confirmed by histopathology examination. Total abdominal hysterectomy, bilateral salpingooophorectomy, and comprehensive staging surgery were performed for the patient, and she was scheduled for chemotherapy after the surgery. She responded well to the treatment and is currently continuing her chemotherapy process.
CONCLUSIONS: There are a great number of reports in the literature regarding mature cystic teratoma of the ovary transformation into malignancy, so these neoplasms must be considered as a possible differential diagnosis and should be evaluated in older individuals with abdominal pain and palpable mass, or those with considerable tumor diameter and raised serum tumor markers.

Non-seminomatous germ cell tumors with structural components from all three cellular lineages are called teratomas. We report a rare case of a primary right adrenal teratoma in a postmenopausal female, presenting with abdominal pain. Ultrasound revealed a complex cystic shadow in the perihepatic region superior to the upper pole of the right kidney, which was suggestive of a complex supra-renal space-sequence-occupying lesion. Computerized tomography revealed a large-sized mature single multilobulated complex cystic lesion in the right hypochondrial lumbar region arising from the right adrenal gland. A right-sided transperitoneal adrenalectomy was performed. The resected mass (18 × 13 × 10 cm) was well encapsulated. Cut surfaces showed cystic mass filled with necrotic gray-white pultaceous material, along with a solid white gelatinous area. Microscopic sections showed a tumor which displayed differentiation along various tissue lineages. After immunohistochemical examinations, the tumor was confirmed to be a mature cystic teratoma. Mature teratomas show a good prognosis, and surgical resection and follow-up remain the standard approach.

Mature cystic teratomas (MCTs) are the most common benign ovarian germ cell neoplasms in women of reproductive age. Rarely, somatic malignancies arise from MCTs, the most common being squamous cell carcinoma. Adenocarcinomas are less common and colorectal adenocarcinomas are extremely rare. We present a case of somatic adenocarcinoma of colorectal type which may pose challenges in diagnosis and treatment. A middle-aged female presented to the Emergency Department with lower abdominal pain. CT scan revealed an 11 cm sharply demarcated left pelvic mass. Laparoscopy showed a left ovarian mass with torsion, a smooth external surface, and thick brownish contents. An intraoperative evaluation was consistent with an adenocarcinoma. Permanent histopathology revealed adenocarcinoma of colorectal phenotype with necrosis. Additional evaluation of the cyst showed benign colonic epithelial lining. The immunohistochemistry (IHC) profile of positive CDX2 and CK20 and negative PAX8, CK7, ER, and PR suggested a colorectal-type somatic adenocarcinoma arising from the MCT and was staged as IA, after negative endoscopic findings. Due to their rarity and atypical symptoms, distinguishing metastatic tumors from MCT-derived somatic malignancies is a challenging process. CT scan and serum tumor markers can be helpful but are not definite. Thorough clinical evaluation and proper staging are necessary after pathologic evaluation. Extensive sampling and IHC can further characterize the origin of the tumor. Diligent sampling and a high index of suspicion in this case clinched the correct diagnosis and clinical management. The patient is being treated for stage IA ovarian cancer as opposed to stage IV metastatic colorectal cancer.

BACKGROUND: Teratomas originating from extra-gonadal account for 15 % of all teratomas, while retroperitoneal site being the least site for teratoma 1-11 %, extremely rare adrenal teratoma is less than 4 % of the retroperitoneal teratomas. Usually, patients are asymptomatic and the tumours are detected incidentally during imaging.
METHODS: A case of a 29 years old female, presented with intractable pain for four weeks. Computed tomography scan study of the abdomen showed an avascular septate cystic lesion measuring 11.6 × 11.4 14.5 cm (cranial-caudal x transverse x anterior-posterior) with central fat density and large punctate calcification in the right suprarenal region displacing the inferior vena-cava laterally, abutting the gall bladder, pancreas and duodenum. Impressions of right adrenal teratoma and less likely adrenal myelipoma were suggested. She remarkably improved one day post operation. During clinic visit a month later, she was completely recovered and resumed her daily activities.
CONCLUSIONS: In adults primary retroperitoneal mature cystic teratoma are uncommon, mostly are secondary tumours and very rare will occur in adrenal gland. Adrenal incidentaloma have been seldom reported mimicking primary mature cystic teratoma. Biochemical and Imaging studies are of great importance in diagnosing and showing relationship of the tumour and other organs. This work has been reported in line with the SCARE criteria (Agha et al., 2018 [1]).
CONCLUSIONS: Primary retroperitoneal tumours are rare and surgery is the main stay of treatment whether it be open or laparoscopic, the latter being best for small lesion for it offers early recovery and complete excision gives excellent prognosis of 100 %.

Acute appendicitis is one of the most common causes of right iliac fossa (RIF) pain in the younger population. However, multiple other pathologies presenting with RIF pain can mimic acute appendicitis. In the female gender, the differentials for RIF pain are broader. Multiple pathologies can present with similar symptomatology that can mimic acute appendicitis, leading to an incorrect diagnosis, unnecessary surgical interventions, and complications. In females of reproductive age, gynaecological causes can present similarly. Here, we present a case of an ovarian teratoma mimicking acute complicated appendicitis. A female of reproductive age presented to our hospital with RIF pain of six days, associated with fever, nausea, vomiting, and anorexia. A clinical diagnosis of acute complicated appendicitis was suspected, and further imaging was arranged to confirm the diagnosis. Imaging showed a normal appendix with a right adnexal mass separated from the ovary, representing a teratoma. She underwent elective surgery for the excision of teratoma after further investigations. Ovarian teratomas are not a common mimicker of appendicitis. One should consider possible gynaecological causes as a differential for RIF pain. Due to the wide variety of differentials, when in doubt, especially in the female gender, further imaging should be considered for confirmation of diagnosis.

Teratomas often occur in the gonads, while Extragonadal mature cystic teratomas are reported occasionally, with the most common site being the omentum. Teratoma in the Douglas sac is extremely rare. we report a rare case of mature cystic Teratoma in the Douglas sac in a 71-year-old woman who underwent laparoscopic surgery. A cyst with a diameter of approximately 6 cm from Douglas was found during surgery, and the mass was separated from both ovaries. Microscopically, the cyst was a mature cystic teratoma that did not originate from the ovary.

OBJECTIVE: To evaluate failure of initial operative therapy (incomplete tumor removal) of ovarian-sparing surgery for pediatric benign ovarian neoplasms.
METHODS: A retrospective review of patients up to 21 years of age who underwent ovarian-sparing surgery for a benign ovarian neoplasm from 2010 to 2016 at 8 pediatric hospitals was conducted. Failure of initial operative therapy is defined as a radiologically suspected or pathologically confirmed ipsilateral lesion with the same pathology as the primary neoplasm within 12 weeks of the initial operation.
RESULTS: Forty patients received imaging within 12 weeks of their primary operation. Sixteen (40%) patients had a radiologically identified ovarian abnormality ipsilateral to the primary lesion, and 5 patients were suspected to have the same lesion as their primary neoplasm. Three of the 5 patients (7.5%) underwent reoperation with pathologic confirmation of the same lesion, resulting in a pathologically confirmed failure of therapy rate of 7.5%. The other 2 patients had serial imaging that subsequently demonstrated no recurrence with lesion resolution. Age, race/ethnicity, laparoscopy vs laparotomy, presence of torsion, pathology, size of lesion, and surgeon specialty were not associated with failure of therapy.
CONCLUSIONS: In most patients who received imaging within 12 weeks of the primary operation for resection of a benign ovarian neoplasm, ovarian-sparing surgery was successful in complete tumor removal, with a low failure of therapy rate. Selected patients with suspected failure of therapy on initial imaging could be serially monitored to determine the need for repeat surgical intervention.

Mature Cystic Teratomas (MCT) of the ovary or Dermoid Cysts are common benign tumours found in 10-20% of women. However, 0.2-2% of those cysts underwent malignant transformation. Squamous Cell Carcinoma (SCC) is the most frequent histological type reported in the literature.As 2021, there are limited reports of malignant tumours arising from MCT with no guidelines related to the management of these atypical cases. Herein, we describe two cases of MCT that evolved into SCC with different stages and prognosis and we review the current literature to date highlighting the potential risk of malignant transformation of these considered benign cysts and the need for strong evidence protocols for staging and treatment of this atypical entity.IMPACT STATEMENTWhat is already known on this subject? Mature Cystic Teratomas are found in 10-20% of women. However, a malignant behavior is observed in 2% of cases.What do the results of this study add? Our paper will describe two cases of malignant transformation of dermoid cyst in an effort to highlight the possible malignant risk of this entity and the need for specific management guidelines.What are the implications of these findings for clinical practice and/or further research? The prognosis of this converted cyst is very poor. By elaborating a standard management protocol for this tumour and operating every large cyst (>10 cm) in postmenopausal women, we may prevent this event.

OBJECTIVE: To assess the preoperative imaging impression and surgeon diagnostic accuracy for pediatric ovarian mature cystic teratomas (MCTs) DESIGN: Retrospective review SETTING: Eleven pediatric hospitals PARTICIPANTS: Patients ages 2 to 21 who underwent surgical management of an ovarian neoplasm or adnexal torsion with an associated ovarian lesion INTERVENTION: None MAIN OUTCOME MEASURES: Preoperative imaging impression, surgeon diagnosis, tumor markers, and pathology RESULTS: Our cohort included 946 females. Final pathology identified 422 (45%) MCTs, 405 (43%) other benign pathologies, and 119 (12%) malignancies. Preoperative imaging impression for MCTs had a 70% sensitivity, 92% specificity, 88% positive predictive value (PPV), and 79% negative predictive value (NPV). For the preoperative surgeon diagnosis, sensitivity was 59%, specificity 96%, PPV 92%, and NPV 74%. Some measures of diagnostic accuracy were affected by the presence of torsion, size of the lesion on imaging, imaging modality, and surgeon specialty. Of the 352 masses preoperatively thought to be MCTs, 14 were malignancies (4%). Eleven patients with inaccurately diagnosed malignancies had tumor markers evaluated and 82% had at least 1 elevated tumor marker, compared with 49% of those with MCTs.
CONCLUSIONS: Diagnostic accuracy for the preoperative imaging impression and surgeon diagnosis is lower than expected for pediatric ovarian MCTs. For all ovarian neoplasms, preoperative risk assessment including a panel of tumor markers and a multidisciplinary review is recommended. This process could minimize the risk of misdiagnosis and improve operative planning to maximize the use of ovarian-sparing surgery for benign lesions and allow for appropriate resection and staging for lesions suspected to be malignant.

Dermoid cyst is a kind of mature cystic teratoma that contains only one germ layer. It usually occurs in the head and neck, retroperitoneal dermoid cysts are uncommon. Teratomas are characterized by mixed density and features like calcification or air-fluid level. Here, we present a case of 40-year-old female with a 12.1 cm × 10.0 cm retroperitoneal fatty mass which showed no calcification and few other specific characteristics of teratoma. Thin and uniform separations were observed. On PET-CT, it was adherent to several retroperitoneal organs like left adrenal gland and left kidney, and had a close relationship with several retroperitoneal vessels like aorta, superior mesenteric arteriovenous, left superior renal artery and inferior vena cava. On PET-CT, mild 18F-FDG uptake was observed. Based on the above imaging findings, a clinical diagnosis of liposarcoma was considered. After laparotomy and open surgery transit through a left vertical incision, the histopathologic examination revealed a retroperitoneal dermoid cyst. During a 2-month follow-up, the patient recovered well without discomfort and recurrence. Comparison between dermoid cyst and liposarcoma in imaging findings was performed. In dermoid cysts, there can be thin and uniform separations, rather than linear, localized and irregular high density in liposarcoma. The difference between dermoid cyst and mature cystic teratoma is yet to be clarified. A review of clinical and histopathological features of retroperitoneal dermoid cyst was also performed to enhance the level of the diagnosis and management.