Evidence of a dual histogenetic pathway of sacrococcygeal teratomas

Abstract

Aims Sacrococcygeal teratomas are rare tumours that occur most frequently in neonates, although adult cases also occur. The molecular pathogenesis of these tumours and their long‐term prognosis is uncertain. We investigated the i(12p) status of a large number of primary sacrococcygeal teratomas in both children and adults, including cases with malignant germ cell tumour elements. Methods and results Fifty‐four sacrococcygeal teratoma specimens from 52 patients were identified, and available follow‐up information was obtained. Fluorescence in‐situ hybridization analysis was performed to identify isochromosome 12p [i(12p)] abnormalities on paraffin blocks of the tumours. Among the 48 paediatric patients, there were 44 teratomas and four tumours with combined teratoma and yolk sac tumour (one of whom also had primitive neuroectodermal tumour). The teratomas included 37 mature teratomas and 11 immature teratomas (four grade 1, two grade 2, and five grade 3). The 44 teratomas lacking a yolk sac tumour component were all negative for i(12p). The four tumours with a yolk sac tumour component were all positive for i(12p). The four adult cases all lacked non‐teratomatous germ cell tumour components, immature elements, and i(12p). Follow‐up information was available for 32 patients. Two patients with teratoma had recurrence, but were alive with no evidence of disease after long‐term follow‐up. One patient with combined teratoma and yolk sac tumour had recurrence 7 months after resection. The other patients were alive with no evidence of disease at last follow‐up. Conclusions Our data suggest that paediatric sacrococcygeal teratomas should be considered as two distinct groups with divergent histogenetic pathways. The prognosis of these tumours is excellent, despite rare recurrence.

Clinicopathologic Features and Chromosome 12p Status of Pediatric Sacrococcygeal Teratomas: A Multi-institutional Analysis

“…[30][31][32] However, the presence of chromosome 12p gains, such as i(12p), is not well defined in pediatric extragonadal teratomas. [13][14][15] In our series, chromosome 12p gains were consistently absent in all SCTs regardless of patient age, gender, SCT type, and presence of immature or nonteratomatous elements. Two patients with associated nonteratomatous components received chemotherapy; a 6-year-old child with residual mature teratoma and medulloepithelioma received chemotherapy before surgery and another 11-month female patient with yolk sac tumor and positive margins received with chemotherapy postoperatively.…”

“…7,17,18 There is no specific grading system for SCTs defined by the World Health Organization, but large series have reported using the Norris criteria to classify these rare tumors, possibly due to their similarity (in clinical behavior) with ovarian teratomas. 7,10,11,14 In our series, 2 of the 5 (40%) SCTs with nonteratomatous components developed in neonates and the other 3 (60%) were seen in older, prepubertal patients (11 months old, 1 year old, and 6 years old). Prompt and complete surgical resection is the cornerstone of management for mature and immature SCTs.…”

“…11,12 The cytogenetic characteristics of pediatric patients with SCTs are not as well studied and have been described in only a few case series. [13][14][15] In this retrospective study, we evaluated the clinicopathologic features and chromosome 12p status of pediatric patients with SCTs using the institutional databases of 2 tertiary US academic medical centers.…”

A unique uterine cervical “teratocarcinosarcoma”: a case report

“…This suggests that this tumor is germ cell derived. In the pure mature or immature teratoma, there is the presence of i(12p) and 12p amplification in non-teratoma germ cell components in ovarian or sacrococcygeal tissues [16, 17]. However, this case showed neither i(12p) nor 12p amplification.…”

Acromegaly and Cushing's syndrome caused by a neuroendocrine tumor arising within a sacrococcygeal teratoma

“…Most present in utero or in infancy with rectal or bladder obstruction, or rarely weakness, pain, or paralysis . A recent study suggests that sacrococcygeal teratomas can be divided into two distinct histological groups, with the presence of i(12)p associated with the presence of germ cell tumor components . Treatment is usually surgical with complete resection or, if the teratoma is part of a mixed‐germ cell tumor, adjuvant platinum‐based chemotherapy may be considered.…”