Sacrococcygeal teratoma with malignant transformation in an adult female: CT and MRI findings

Abstract

Abstract. This report describes a case of sacrococcygeal teratoma with adenocarcinomatous transformation in a 45-year-old woman. This is an infrequent location for teratoma in adults and malignant transformation has rarely been described. Prognosis depends on complete excision. Clinical manifestations, imaging aspects and histological findings of this case are presented. CT and MRI adequately document the mixed cystic and solid nature of the tumour, its extension and relations with adjacent structures, allowing accurate pre-operative planning.Sacrococcygeal teratoma is the most common solid neoplasm in neonates, with an estimated prevalence of 1 in 35 000-40 000 live births. They can be diagnosed prenatally by fetal ultrasound and 50-70% are found during the first few days of life. 80% are diagnosed by the sixth month and fewer than 10% beyond the age of 2 years [1,2]. Reported cases of sacrococcygeal teratomas in adults are rare. Treatment consists of complete surgical resection. Long-term survival is possible for malignant tumours, but incomplete surgical removal carries a poor prognosis. If the tumour invades adjacent structures, neoadjuvant pre-operative combination chemotherapy should be given [7].We report an unusual case of a 45-year-old woman with intestinal and urinary obstructive symptoms due to a large sacrococcygeal teratoma with adenocarcinomatous transformation. CT and MRI appropriately demonstrated the combined cystic and solid nature of the tumour, its extension and relations with adjacent structures, allowing accurate pre-operative planning. Case reportA 45-year-old woman with a 1-year history of gradually increasing lower back and pelvic pain, presented with constipation, dysuria and urinary frequency that had progressively developed over 2 months. There was an obstetrical history of dystocic forceps deliveries at ages 21 and 27. On gynaecological and rectal examination a large palpable mass was found in the right pelvis, posterior to the rectum. Neurological examination was unremarkable. Alpha-fetoprotein, carcinoembryonic antigen and human chorionic gonadotropin levels were normal. On pelvic CT (Figure 1) a regularly marginated thin walled cystic mass measuring 15 cm611.5 cm610.5 cm was identified, anterior to the sacrum and coccyx and extending inferiorly into the left ischiorectal fossa, compressing the urinary bladder and sigmoid colon and anteriorly displacing the rectum and vagina. Its content had homogeneous density near to that of water (10 Hounsfield Units), with a discrete amount of floating fat. At the coccyx bone level, a contrast enhancing 2.5 cm solid nodule was also evident as vegetation from the posterior wall. No evidence of bone destruction or invasion of the adjacent structures was found. Hysterectomy, bilateral adnexectomy and biopsies of the tumour were performed at laparotomy. Histopathological evaluation showed the wall of the cystic portion to be composed of a fibrous capsule with an inner lining of respiratory epithelium and areas of squamous epithelium. The described ...

Adenocarcinoma Within a Paracoccygeal Teratoma in an Adult: Report of a Case

“…Some patients present with recurrent pilonidal cyst infections or chronic fistulas. 11,19,20 Our patient presented with a painful growing paracoccygeal mass, causing skin ulceration. On examination, a rectal mass is usually palpable.…”

“…6 Computed tomography and MRI are important for characterization of the mass and evaluation of its extension, and its relationship to other structures. 19,21 The only effective treatment for PCT is early and complete excision. This operation is performed through a posterior approach, with the patient in the jackknife position, and the coccyx should be excised along with the neoplasm, since microscopic nests of neoplastic cells are commonly found in or immediately adjacent to the bone.…”

Somatic malignant transformation in a sacrococcygeal teratoma in a child and the use of F18FDG PET imaging

“…Teratomas have the potential for malignant transformation in which one of the components histologically resembles a somatic malignancy [7][8][9]. This type of transformation rarely occurs and has only previously been reported in adults [10]. We report a somatic malignant transformation within a SCT in a 6-year-old female.…”

Sacrococcygeal teratoma in an adolescent.

“…The other components included scant residual simple mucinous epithelium, respiratory tract wall of ciliated pseudostratified columnar epithelium, a muscular layer with JBR-BTR, 2012, 95: 322-324. are common in infants. Most adult SCTs are cystic, and only 1 to 2% are malignant (2,3,5).…”