Dysontogenetic cysts, commonly referred as dermoid cysts or teratoid cysts, are hamartomas which may contain various derivatives of endoderm, mesoderm and ectoderm7. The majority of cases is reported in the midline of the body and especially in testes and ovaries. The most common site in the head and neck region is the lateral eyebrow, the so-called angular dermoid, and approximately 6.5% of the cases occur in the oral cavity. The teratoid cyst of the floor of the mouth is distinctly uncommon, with only a few cases reported, usually in the anterior portion8,14.
Three theories with regard to the origin of cysts in the floor of the mouth were found in literature. According to the 1st and most prevalent theory, these cysts originate from embryonic cells of the 1st and 2nd branchial arches during the 3rd/4th week of embryonic life. The 2nd theory explains the pathogenic mechanism of the acquired form, which may be due to the implantation of epithelial cells subsequent to accidental or surgical injury (traumatic causes, iatrogenic antecedents, or an occlusion of a sebaceous gland duct). Lastly, the 3rd theory maintains that these cysts are considered a variation of the cyst of the thyroglossal pore6. With regard to the etiology of dermoid and teratoid cysts in this site, there is much theory, but the most accepted is a possible sequestration of ectodermal tissue in the midline at the time of fusion of the first (mandibular) and second (hyoid) brachial arches2,10.
Histologically, the dermoid cyst differs from epidermoid cyst only in the presence of normal or dysmorphic adnexal appendages within its walls, usually sebaceous glands or abortive hair follicles. The teratoid cyst is considered if the cyst wall contains other elements, such as muscle or bone11. Surgical approaches for excision have been the treatment of choice for dermoid or teratoid cyst, including intraoral and extraoral skin incisions12. Most of the authors recommend conservative surgical removal, trying not to rupture the cyst, as the luminal contents may act as irritants to fibrovascular tissues, producing postoperative inflammation. Recurrence and malignant transformation of oral cysts are unlikely after treatment8,9.
This paper presents a case of teratoid cyst in a child with emphasis on the management and follow-up of six months.
Teratomas are composed of somatic cells from two or more germ layers (ectoderm, mesoderm or endoderm)8. Although the child's age being the most affected, in adults it occurs at different locations, such as mediastinum, sacrococcix, retroperitoneum and more often in the gonads7,13. Retroperitoneal teratomas in adults are rare, representing only 1-11% of all primary tumors in that anatomic region9, generally are benign and asymptomatic in the first stages. However when symptoms occur, they are typically due to their size, presenting with abdominal distension and a palpable mass12. Diagnosis can be made by ultrasound, that can identify solid or cystic components, computerized tomography and magnetic resonance imaging, which are both superior than ultrasound to evaluate tumoral extention and relation to adjacent organs2,4,5,12,13. Angiography can be used to detect and evaluate the blood supply. In this article, it is presented a case of a giant retroperitoneal treated with surgical resection.
A 42-year-old male was suffering from an insidious abdominal distention for the last 13 years, that was more remarkable in the initial three years. There was no fever, abdominal pain, or bowel complaints. He denied smoking or drinking abuse. There was not any kind of disease in patient's past or family medical history. He had been treated with spironolactone years before, with no previous investigation, and it was suspended by the occurrence of gynecomastia. On admission, he was clinically in good condition, and presenting an important abdominal distention without tenderness, and bowel sounds preserved. The rest of the examination was unremarkable. Admission laboratory tests showed no abnormalities. An abdominal computerized tomography revealed a mass occupying all regions in the abdominal cavity, showing no apparent origin. The patient underwent exploratory laparotomy that showed a mass weighing approximately 30 kilograms (Figure 1), whose origin was in the retroperitoneum completely displacing the left kidney to the right iliac fossa. The patient did well post-operatively and is currently assymptomatic and has been followed as an outpatient. Histopathological analisys demonstrated heterogeneous contents, with predominant cystic formations and other unctuous and soft components, and the diagnosis of mature teratoma was confirmed by microscopy (Figure 2).
Desenvolvido por Surya MKT