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

Catarino, A.

Cunha, Teresa Margarida

Monteiro, M.

Tomé, V.

British Journal of Radiology

English

Repositório Comum

Case reportSacrococcygeal teratoma with malignant transformationin an adult female: CT and MRI findings1M MONTEIRO, MD, 1T M CUNHA, MD, 2A CATARINO, MD and 3V TOME´, MDDepartamentos de 1Imagiologia, 2Patologia Morfolo´gica e 3Oncologia Me´dica, Instituto Portugueˆs deOncologia de Francisco Gentil (I.P.O.F.G.) Centro Regional de Lisboa, R. Prof. Lima Basto, 1099-023Lisboa Codex, PortugalAbstract. This report describes a case of sacrococcygeal teratoma with adenocarcinomatoustransformation in a 45-year-old woman. This is an infrequent location for teratoma in adults andmalignant transformation has rarely been described. Prognosis depends on complete excision.Clinical manifestations, imaging aspects and histological findings of this case are presented. CTand MRI adequately document the mixed cystic and solid nature of the tumour, its extension andrelations with adjacent structures, allowing accurate pre-operative planning.Sacrococcygeal teratoma is the most commonsolid neoplasm in neonates, with an estimatedprevalence of 1 in 35 000–40 000 live births. Theycan be diagnosed prenatally by fetal ultrasound and50–70% are found during the first few days of life.80% are diagnosed by the sixth month and fewerthan 10% beyond the age of 2 years [1, 2]. Reportedcases of sacrococcygeal teratomas in adults are rare.Reviews of the literature by Head et al [3], Ahmedand Pollock [4], Ng et al [5] and Bull et al [6] founda total of 88 reported cases, with only 16 describedas malignant or with malignant transformation.Treatment consists of complete surgical resec-tion. Long-term survival is possible for malignanttumours, but incomplete surgical removal carriesa poor prognosis. If the tumour invades adjacentstructures, neoadjuvant pre-operative combina-tion chemotherapy should be given [7].We report an unusual case of a 45-year-oldwoman with intestinal and urinary obstructivesymptoms due to a large sacrococcygeal teratomawith adenocarcinomatous transformation. CTand MRI appropriately demonstrated the com-bined cystic and solid nature of the tumour, itsextension and relations with adjacent structures,allowing accurate pre-operative planning.Case reportA 45-year-old woman with a 1-year history ofgradually increasing lower back and pelvic pain,presented with constipation, dysuria and urinaryfrequency that had progressively developed over2 months. There was an obstetrical history ofdystocic forceps deliveries at ages 21 and 27.On gynaecological and rectal examination a largepalpable mass was found in the right pelvis,posterior to the rectum. Neurological examinationwas unremarkable. Alpha-fetoprotein, carcino-embryonic antigen and human chorionic gonado-tropin levels were normal. On pelvic CT(Figure 1) a regularly marginated thin walledcystic mass measuring 15 cm611.5 cm610.5 cmwas identified, anterior to the sacrum and coccyxand extending inferiorly into the left ischiorectalfossa, compressing the urinary bladder andsigmoid colon and anteriorly displacing therectum and vagina. Its content had homogeneousdensity near to that of water (10 HounsfieldUnits), with a discrete amount of floating fat.At the coccyx bone level, a contrast enhancing2.5 cm solid nodule was also evident as vegetationfrom the posterior wall. No evidence of bonedestruction or invasion of the adjacent structureswas found. Hysterectomy, bilateral adnexectomyand biopsies of the tumour were performed atlaparotomy. Histopathological evaluation showedthe wall of the cystic portion to be composed of afibrous capsule with an inner lining of respiratoryepithelium and areas of squamous epithelium.The described solid nodule was an adenocarci-noma. These findings were concordant withmalignant transformation in a sacrococcygealteratoma, and the patient was referred to ourinstitution for further evaluation and treatment.Subsequent MRI, for better pre-excisionalevaluation, showed two distinct, well circum-scribed, thin walled cystic components withReceived 28 June 2001 and in revised form 11 January2002, accepted 21 January 2002.Address correspondence to Ma Margarida Monteiro,Servic¸o de Radiologia, Hospital da Forc¸a Ae´rea,Azinhaga dos Ulmeiros, 1600-777 Lisboa, Portugal.E-mail: hfa.imagiologia@emfa.ptThe British Journal of Radiology, 75 (2002), 620–623 E 2002 The British Institute of Radiology620 The British Journal of Radiology, July 2002homogeneous high protein and serous fluidcontents, respectively (Figure 2). There was adiscrete lamella of fat at the right periphery ofthe inferior cyst. Separating the cysts, a masscorresponding to the solid nodule on CTwas evident after administration of gadolinium(Figure 3). Coronal and sagittal planes (Figure 4)displayed the tumour’s hourglass shape, with therectosigmoidal transition seen tightly compressedbetween the two cystic components. Midlinesagittal images clearly illustrated the solid com-ponents close relation with the anterior surface ofb.3b.2b.1Figure 2. MRI reveals two indepen-dent cystic portions. Axial scansshow (a) a right-sided superior and(b) a left-sided inferior cyst withhomogeneous contents. The supe-rior cyst shows hyperintense signalon both (a.1) T1 and (a.2) T2weighted images, compatible withhigh protein fluid. The inferior cystshows (b.1) hypointense signal onT1 and (b.2) hyperintense signalon T2 weighted images, indicatingserous fluid. (b.1) Only the discretelamella of hyperintense signal, visi-ble at the right periphery of theinferior cyst (arrowhead) corres-ponds to pure fat content, as it is com-pletely suppressed on a fat saturatedsequence (b.3). a.1 and b.1, T1weighted images (TR, 426 ms; TE,8.0 ms); a.2 and b.2, T2 weighted turbospin echo images (TR, 5404 ms; TE,120 ms); b.3, fat saturated T1 weightedimage (TR, 680 ms; TE, 8.0 ms).Figure 3. Axial T1 weighted (TR, 426 ms; TE,8.0 ms) scan. (a) Without contrast the adenocarcino-matous nodule has hypointense signal, indistinguish-able from the content of the inferior cyst. (b) Aftergadolinium administration the nodule becomes dis-tinctively hyperintense.Figure 4. (a) Coronal and (b) midline sagittal T2weighted turbo spin echo MR images (TR, 6859 ms;TE, 150 ms). The tumour has an hourglass appear-ance with the rectosigmoidal transition tightly com-pressed between the cystic components. The solidcomponent at the isthmus (arrowhead) is seen inclose relation with the anterior surface of the coccyx.No evidence of invasion of the surrounding structureswas seen in any of the planes.(a) (b) (c)Figure 1. CT scans show (a) a thinwalled cystic mass with homoge-neous hypodense content anterior tothe sacrum, compressing the urinarybladder and anteriorly displacingthe rectum and vagina. A discreteamount of floating fat can be seenanteriorly (arrowhead). (b) At aninferior level a contrast enhancingsolid nodule is seen, apparently vege-tating from the posterior wall, inclose relation with the coccyx. Thereis no evidence of bone destruction.(c) The mass extends inferiorly intothe left ischiorectal fossa.Case report: Sacrococcygeal teratoma with malignant transformation621The British Journal of Radiology, July 2002the coccyx. As on CT, there was no evidence ofinvasion of the rectal or bladder wall, surroundingfat, pelvic floor muscles or osseous structures inany of the planes, nor was regional lymph nodeenlargement seen.The patient was re-operated on, with completeexcision of the tumour. On gross examinationthe surgical specimen looked like a biloculatedcyst filled with sebum, haemorrhagic material of anecrotic appearance and serous fluid, separated bya firm heterogeneous solid nodule.Microscopically, the wall of the cyst was linedwith mature stratified squamous keratinizingepithelium. Areas of respiratory epithelium werealso present. The solid region was composed ofirregular nests of neoplastic glands with morpho-logical features of a moderately differentiatedadenocarcinoma, infiltrating the surroundingstroma with desmoplastic features (Figure 5),hence confirming the diagnosis of adenocarcino-matous transformation in a mature teratoma. Softtissue margins were negative for tumour, whichwas found confined to the limits of the surgicalspecimen. No angioinvasion was identified.The patient underwent post-operative adjuvantcombination chemotherapy with three cycles ofbleomicin (30 mg, day 1 and day 8), etopo-side (100 mg m22, days 1–5) and cisplatinum(20 mg m22, days 1–5). There was no evidenceof recurrence by the twelfth month of follow-up.DiscussionTeratomas are composed of tissues that arestrange to the anatomic site of appearance anddisposed in a disorganized fashion. They derivefrom embryonic pluripotent cells and may havevarious degrees of maturation, according to whichthey are classified as mature, immature, andmalignant (malignant tissue of germ cell origin)[1, 2]. Teratomas with malignant transformationcontain malignant cells derived from maturetissues. Pluripotent cells are normally present inthe gonads, and may also be found in abnormalsequestered midline embryonic rests. Accordingly,teratomas are found with decreasing frequency inthe ovaries and testis, mediastinum, retroperito-neal space, sacrococcygeal zone, pineal and otherintracranial locations [5]. Sacrococcygeal terato-mas are thought to originate from multipotentialcells in Henson’s node, which migrates caudally torest in the coccyx [8]. They may grow postero-inferiorly into the gluteal area and/or antero-superiorly into the abdominopelvic cavity [9]. Thereis a tendency among the paediatric populationtoward malignant transformation of sacrococcy-geal teratomas with increasing age. However, incase reports concerning adult patients, benigntumours predominate [5]. Exclusively presacraltumours present later than those with an externalcomponent, and have a higher prevalence ofmalignant transformation. They can present withchronic fistula, low back pain or obstructivesymptoms of the gastrointestinal or genitourinarytracts. In the reported case the sacrococcygealteratoma might have been the cause of thedystocic forceps deliveries. Conventional studiesperformed with contrast material may demon-strate extrinsic narrowing with anterior displace-ment of the rectum, lateral displacement of therectosigmoid colon and compression of theurinary bladder against the anterior abdominalwall, caused by a space occupying presacrallesion. CT and MRI are the most importantinvestigations for characterization of the mass,evaluation of its intrapelvic extension and rela-tionship to other structures. Most commonly,teratomas appear as a complex mass with roughlyequal amounts of solid heterogeneous and cysticareas with or without septations. They alsofrequently present as thick walled cystic masses,sometimes multiloculated, that may contain fat,calcified elements and/or small solid nodules, asin the reported case. Predominantly solid massesare uncommon [2]. The reported case, with twocystic components, a solid nodule and a smallamount of fat, was suggestive of the secondFigure 5. Photomicrographs (haematoxylin-eosin stain,original magnification (a) 640; (b) 620) show (a)the wall of the cyst composed of fibrous tissue withan inner lining of mature squamous epithelium andrespiratory epithelium, and (b) irregular nests ofmoderately differentiated adenocarcinomatous glandsinfiltrating the surrounding stroma.M Monteiro, T M Cunha, A Catarino and V Tome´622 The British Journal of Radiology, July 2002described pattern of teratoma. Complex, pre-dominantly solid tumours are more likely to bemalignant and significant areas of necrosis withinthe tumour, or poor definition of adjacent soft-tissue planes, are signs suggestive of malignancy.Invasion of adjacent structures, rather than simpledisplacement, sacral destruction and secondaryfindings such as locoregional lymph node anddistant metastases are clearly indicative of malig-nancy [1, 2]. Nevertheless, imaging features alonedo not allow definite differentiation betweenbenign teratomas and those with malignanttransformation. In the absence of aspects sug-gestive of malignancy, benignity must not beassumed.Differential diagnosis of sacrococcygeal massesvaries with their nature. In the adult, presacro-coccygeal simple cystic lesions may correspond toanterior meningocele, rectal or anal duplicationcyst or anal gland cyst. In the appropriate clinicalcontext they may also represent abnormal collec-tions like seroma or urinoma. In the presence of amultiloculated cystic lesion, a tail gut cyst (retro-rectal cystic hamartoma) must be considered.Denser and more complex lesions may representchronic retrorectal abscess, pilonidal or dermoidcyst, soft tissue or bone tumours. With destruc-tive or invasive imaging features, a malignantnature must be considered including sarcomatoustumours, chordoma or metastases. Osteomyelitisof the sacrum may also cause osseous destructionwith associated soft tissue mass. Sacrococcygealteratoma should be included in the differentialdiagnosis, whatever the nature of the lesion [1, 7].CT is the most sensitive method of demonstrat-ing calcification/ossification, which may be visiblein over 50% of malignant tumours [1], and theintegrity of adjacent cortical bone. Fat–fluid orfluid–debris levels may appear with complex cystcontents. MRI better depicts cystic elements,the contents of which might be inferred fromsignal intensity patterns on different sequences.Fat components can be identified by either CT orMRI. CT and MRI are complementary in theevaluation of sacrococcygeal column anomaliessuch as spinal dysraphism, sacral agenesis,pressure erosion and remodelling that can beassociated with sacrococcygeal teratomas.The treatment for all sacrococcygeal teratomasconsists of early and complete surgical excisionwith coccygectomy. This bone may contain anidus of pluripotent cells that increase recurrencerates to 37% when not excised [1, 5, 10]. Surgicalapproach depends on size and topographiclocation of the tumour [10–13]. Owing to itsdirect multiplanar imaging capacities, MRI allowsa better topographic evaluation of the tumourthat is important for accurate pre-operativeplanning. Solid teratomas may be very vascular,causing important intraoperative haemorrhage[11, 14]. Pre-operative angiography may be con-sidered for previous blood supply evaluation andembolisation in larger tumours [1, 8]. If completeresection is accomplished, benign teratomas havea good prognosis and long-term survival is pos-sible with malignant tumours. Because malignanttransformation is rare there has been no standardrecommendation for the use of chemotherapy orradiation and the best treatment plan seems tobe referral to an oncology centre, where indivi-dualized multimodality therapy can be achieved[6, 12].References1. Keslar PJ, Buck JL, Suarez ES. Germ cell tumorsof the sacrococcygeal region: radiologic-pathologiccorrelation. Radiographics 1994;14:607–20.2. Wells RG, Sty JR. Imaging of sacrococcygeal germcell tumors. Radiographics 1990;10:701–13.3. Head H, Gerstein J, Muir R. Presacral teratomain the adult. Am Surg 1975;41:240–8.4. Ahmed HA, Pollock DJ. Malignant sacrococcygealteratoma in the adult. Histopathology 1985;9:359–63.5. Ng EW, Porcu P, Loehrer PJ. Sacrococcygealteratoma in adults: case reports and a review ofthe literature. Cancer 1999;86:1198–202.6. Bull J Jr, Yeh KA, McDonnell D, Caudell P, DavisJ. Mature presacral teratoma in an adult male: acase report. Am Surg 1999;65:586–91.7. Green DM, Tarbell NJ, Schamberger RC. Solidtumors of childhood—germ cell tumors. In: DeVitaJT Jr, Hellman S, Rosenberg SA, editors. Cancer:principles & practice of oncology. Philadelphia, PA:Lippincott-Raven, 1997:2118–20.8. Audet IM, Goldhahn RT Jr, Dent TL. Adultsacrococcygeal teratomas. Am Surg 2000;66:61–5.9. Altman RP, Randolph JG, Lilly JR. Sacrococcygealteratoma: American Academy of Pediatrics surgicalsection survey. J Pediatr Surg 1973;9:389–98.10. Mahour GH. Sacrococcygeal teratomas. CA CancerJ Clin 1988;38:362–7.11. Localio SA, Eng K, Ranson JHC. Abdominosacralapproach for retrorectal tumors. Ann Surg1980;191:555–60.12. Lopes A, Pearson S, Roberts J, et al. Case report:immature presacral teratoma in an adult female.Gynecol Oncol 1990;38:135–7.13. Lee R, Symmonds R. Presacral tumors in thefemale clinical presentation, surgical managementand results. Obstet Gynecol 1988;71:216–21.14. Miles RM, Stewart GS. Sacrococcygeal teratomasin adults. Ann Surg 1974;179:676–83.Case report: Sacrococcygeal teratoma with malignant transformation623The British Journal of Radiology, July 2002

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

https://comum.rcaap.pt/bitstream/10400.26/15481/1/Sacrococcygeal%20teratoma%20with%20malignant%20transformation%20in%20an%20adult%20female%20CT%20and%20MRI%20findings.pdf

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

Abstract

Similar works

Full text

Available Versions

Repositório Comum