Rare extragonadal teratomas in children: complete tumor excision as a reliable and essential procedure for significant survival. Clinical experience and review of the literature

Abstract

Background: Extragonadal teratomas are rare tumors in neonates and infants and can sometimes show unusual, distinctive feature such as an unusual location, a clinical sometimes acute, presentation and a "fetiform" histotype of the lesion. We have extrapolated, from our entire experience of teratomas, 4 unusual cases, mostly operated as emergencies; 2 of them were treated just after birth. Aim of this paper is to report the clinical and pathological findings, to evaluate the surgical approach and the long-term biological behaviour in these cases, in the light of survival and current insights reported in the literature.

Material and methods: The Authors reviewed the most significant (Tables I and II) clinical, laboratory, radiologic, and pathologic findings, surgical procedures, early and long-term results in 4 children, 1 male and 3 females (M/F ratio: 1/3), suffering from extragonadal teratomas, located in the temporo-zygomatic region of the head (Case n. 1, Fig. 1), retroperitoneal space (Case n. 2, Fig. 2) ,liver (Case n. 3, Figg. 3-5), kidney (Case n. 4, Fig. 6, 7), respectively. Of the 4 patients, 2 were treated neonatally (1 T. of the head, 1 retroperitoneal T.) A prenatal diagnosis had already been made in 2 of the 4 patients, between the 2nd and 3rd trimester of pregnancy, All the infants were born by scheduled caesarean section in a tertiary care hospital and were the immediately referred to thew N.I.C.Us. Because of a mostly acute clinical presentation, the 4 patients were then referred to the surgical unit at different ages: 7 days, 28 days, 7 months, and 4 years respectively. The initial clinical presentation (Table II) was consistent with the site of the mass and/or its side effects. The 2 newborns (Case 1 and 2) both with a prenatally diagnosed mass located at the temporozygomatic region and in the abdominal cavite respectively, already displayed, at birth a mass with a tendency to further growth. The symptoms and signs described to the primary care physician by the parents of the 2 patients suffering from intra-abdominal tumours (Cases n. 3, 4) were: swelling of the epigastrium and left hypochondrium due to a progressively growing hard mass, without impairment of the general, conditions in case n.3 (teratoma of the liver),while recurrent abdominal pain lasting for the 5 months was described in case n.4(retroperitoneal teratoma), followed by the development of an evident hard mass occupying the entire abdomen. In this case the symptoms suddenly worsened, with acute pain extending to the entire abdomen, high fever (>39° C), polypnea, anemia, deterioration of the general conditions and a rapid further enlargement of the mass. Antibiotic therapy was ansuccessful. The young child underwent a radiologic investigation (Fig. 6) that showed a large calcified mass in the left retroperitoneal space, associated with pleural effusion, In all the patients except for the Case n. 3, emergency surgical management was required and, in accordance with recommended practice, the procedure was complete exeresis.

Results (table i): All the 4 patients had an uneventful postoperative course. Clinical surveillance and tests of AFP and other markers were scheduled every 6 months for the first years and annually thereafter. At the current date they are alive, disease-free and have not suffered any recurrence with a follow-up as reported in Table I, of 7 years in case n. 2; 23 years in case n. 1; 42 years in case n. 3 and 36 years in case n. 4.

Conclusions: Some extragonadal teratomas of childhood of may rarely arise in the solid organs (liver, kidney), in the retroperitoneal space or the cranio-facial region, and also show unique histotype childhood characteristics ("fetiform") which distinguish them from more common cases. Being congenital tumours, prenatal diagnosis by US scan is extremely important in order to organize proper perinatal care in appropriate facilities where it is possible to define the diagnosis and carry out emergency surgery. An emergency procedure is frequently dictated both by complications related to the mass eddect and by the need to define the histology of the whole mass rather than just small biopsy specimens, Some teratomatas can hide more or less extensive islands of immaturity signs of malignant transformation that are clinically evident. It should be remembered that high serum levels of alpha-fetoprotein and calcficationof the imaging study, that are usually pathognomonic elements for fiagnosis, nay be lacking in abdominal lesions. Moreover, some additional specific diagnostic problems can be faced by either the radiologist (differential diagnosis from acquired or congenital cystic lesions, identification of the primary site of origin in the liver kidney or retroperitoneal space). Or the histopathologist (exclusion of renal metastasis of a primary gonadal teratomas of a glomerular and tubular differentiation a Wilm's tumour). The prognosis is generally benign, although the AIEOP guideline pointed out that high levels of circulating markers, including AFP, in children affected by mature or immature teratomas, could indicate rhe presence of micro-foci of YST, marking them out as at high risk. The UKCCSG II and the SFOP indicates AFP values exceeding 10,000 ng/ml as the threshold identifying a group of patients with a severe prognosis. The treatment indicated is early, complete exeresis, followed by a careful, exstensive, microscopic examination, associated, if necessary, with adjuvant chemotherapy. Finally, to improve the prognosis, close, long-term clinical, laboratory and imaging surveillance is necessary, at shorter intervals during the first 5 years after the exeresis and annually thereafter.