J Clin Pathol: first published as 10.1136/jcp.33.11.1058 on 1 November 1980. Downloaded from J Clin Pathol 1980;33:1058-1063 Mixed hepatoblastoma in the adult: case report and review of the literature RP HONAN AND MT HAQQANI From the Department of Pathology, Walton Hospital, Rice Lane, Liverpool L9 JAE, UK SUMMARY A case of mixed hepatoblastoma in a woman is described. A survey of the English literature reveals 13 cases acceptable as mixed hepatoblastoma; these have been described and published under a variety of names. Difficulties in nomenclature and the histology of these cases are discussed. Diagnosis depends on the identification of both malignant mesenchymal and malignant epithelial elements. The former include myxoid connective tissue resembling primitive mesenchyme and areas resembling adult fibrosarcoma. Mature fibrous tissue with calcification and bone for- mation may be seen. Epithelial areas show tissue resembling fetal liver, poorly differentiated epithelial cells, and/or areas of adenocarcinoma. The current view on histogenesis is also given. Most hepatoblastomas occur in children under the mixedtumour,6carcino-osteochondromyxosarcoma,5 copyright. age of 2 years.' Hepatoblastoma in adults is ex- and rhabdomyosarcohepatoma.7 tremely rare, and the prognosis is much worse than in the mixed hepatoblastoma of childhood. Case report The literature of mixed hepatoblastoma in adults has until recently been confused, and the true inci- CLINICAL PRESENTATION dence of the tumour obscured, owing to the various A Chinese woman aged 27 had been resident in names used by different authors to describe their England for eight years. She gave a history of cases. The commonest pseudonym is 'mixed malig- 18 months' intermittent right-sided chest pain http://jcp.bmj.com/ nant tumour',2-4 an ambivalent term which merely and upper abdominal discomfort. She had pre- denotes the presence in one tumour of tissues viously been well. There was pyrexia, a right-sided derived from more than one germ layer. Study of the pleural effusion, and a smooth, tender, markedly histology in these cases shows that many of them enlarged liver. Laboratory findings included: Hb 11 fulfill the criteria for a diagnosis of mixed hepato- g/dl (microcytic, hypochromic blood film), white cell blastoma. Sometimes, indeed, the authors admit that count 12-5 x 109/1 (neutrophil polymorphs 90%). only an origin from embryonic cells can satisfactorily Biochemistry, including liver function tests, was on September 26, 2021 by guest. Protected explain their histogenesis. Presumably there is a essentially normal. Blood cultures and screening for reluctance to use the suffix 'blastoma' in cases tuberculosis were negative. occurring in elderly patients, although there are no A diagnosis of hepatic amoebic abscess was essential histological differences between these thought most likely. Metronidazole was started. tumours and hepatoblastoma of infancy. It should, Faecal parasites were repeatedly negative, but however, be stated that not all cases described as serology showed a weakly positive fluorescent 'mixed tumour' represent hepatoblastoma. This is antibody test for Entamoeba histolytica (titre 1/16). made clear when surveying Milman's cases,5 An abdominal x-ray confirmed hepatomegaly, and collected from a review of the earlier literature. True an opacity overlying the right kidney was noted. hepatic teratoma, for example, may occur. Other Two years previously an abdominal x-ray had names under which mixed hepatoblastoma of the shown a raised right diaphragm and a probable adult has masqueraded include hepatic embryonic small right pleural effusion. The patient's condition gradually deteriorated. In view of the failure to Received for publication 25 March 1980 respond to treatment a diagnosis of neoplasm was 1058 J Clin Pathol: first published as 10.1136/jcp.33.11.1058 on 1 November 1980. Downloaded from Mixed hepatoblastoma in the adult: case report and review of the literature 1059 There were extensive areas of calcification and necrosis. The elevation of the diaphragm resulted in compression of the pericardium, causing death by cardiac tamponade. The right lung contained many subpleural, soft white secondary deposits, up to 2 cm in diameter. There were no metastases to the peritoneum, and all the other organs appeared normal for age. Histology of liver tumour The tumour has a variegated appearance with a predominance of mesenchymal elements, which vary from primitive to mature, mixed with primitive and poorly or well differentiated epithelial cells. The . i..fI N .. a II .s A 0 1 2 3 4 5 inches cells of the epithelial tissue vary in size and have dark, densely hyperchromatic polygonal, round, or oval nuclei and as Fig. 1 Large uninodular tumour showing areas of abundant cytoplasm arranged haemorrhage and necrosis well demarcatedfrom the cords or trabeculae separated by thin fibrous septa adjacent congested liver. indistinguishable from primary hepatocellular carci- noma (Fig. 2). Sometimes there is a poorly differ- seriously considered. At laparotomy there was a entiated acinar appearance (Fig. 3); occasionally massive primary liver tumour, from which a wedge clefts separating groups of small and primitive cells biopsy was taken. The patient died the same day. resembling fetal liver can be seen. The acinar structures (Fig. 3) probably represent ductular POSTMORTEM FINDINGS differentiation. In the cellular areas, the mesenchymal copyright. The liver was markedly enlarged (weight 4510 g). elements take the form of spindle-shaped cells with There was a huge, uninodular tumour (Fig. 1), elongated tapering nuclei, which show marked approximately 25 cm in diameter, arising in the pleomorphism with multinucleate forms and in- superior aspect of the right lobe and extending creased mitotic activity. In some areas there are upwards, pushing the diaphragm high into the interlacing bundles of spindle cells reminiscent of thoracic cavity. It appeared well demarcated, by fibrosarcoma (Fig. 4). No rhabdomyoblasts were a pseudocapsule, from the remaining liver, which found. was no congested but showed evidence of cirrhosis. In many areas, however, particularly in the http://jcp.bmj.com/ on September 26, 2021 by guest. Protected Fig. 2 Trabeculae of well goN*^^4>~~ w diffierentiated epithelial cells , ^ ; separated by thin fibrous septa x8 tf indistinguishable from t4 tp"tOw*>hepatocellular carcinoma. sf 9__ v Haematoxylin and eosin ~X! * +|v ......... ,}.|x 125. J Clin Pathol: first published as 10.1136/jcp.33.11.1058 on 1 November 1980. Downloaded from 1060 Honan and Haqqani Fig. 3 Poorly differentiated acinar appearance. H and E x 125. calcified region, the morphology is different, with mesenchymal elements show areas resembling fibro- poorly cellular, hyalinised fibrous tissue showing sarcoma, spindle-shaped cells with tapering nuclei, widespread calcification with prominent osseous marked pleomorphism, and multinucleated cells. copyright. differentiation (Fig. 5). Nowhere was there evidence In addition, there is dense fibrous tissue and bone. of osteosarcoma, nor was any cartilage found. The epithelial elements show well differentiated Sections from the pulmonary metastases show poorly hepatocellular carcinoma-like areas, poorly differ- differentiated epithelial cells, again showing cleft entiated acinar appearance, or sheets of undifferen- formation between adjacent cell groups and tiated cells. The combination of mesenchymal and occasional acini, together with malignant mesenchy- epithelial elements enable the diagnosis of mixed mal tissue. hepatoblastoma to be made. To summarise the histology, the malignant http://jcp.bmj.com/ on September 26, 2021 by guest. Protected S2- Fig. 4 Malignant ; If> mesenchymal tissue showing pleomorphic spindle-shaped cells andfibrosarcoma-like areas. Hand E x 125. J Clin Pathol: first published as 10.1136/jcp.33.11.1058 on 1 November 1980. Downloaded from Mixed hepatoblastoma in the adult: case report and review of the literature 1061 literature where the criteria for a diagnosis of adult mixed hepatoblastoma appear to have been fulfilled. The first two cases are from Milman's review of 'mixed tumours' of the liver.5 Descriptions are brief, and illustrations were not available, but it seems clear that mesenchymal and epithelial tissues were shown in a malignant uninodular tumour, both cases being without extrahepatic metastases. Many other cases of 'mixed tumour' were reviewed by Milman, but details are scanty and in general point to some other alternative diagnosis such as malig- nant teratoma or carcinosarcoma. Cases 3, 4, and 6-12 are clearcut, being fully described and illustrated. Cases 2 and 6 show the tumour occurring in cirrhosis. Here the diagnosis must be made with care to exclude carcinosarcoma. Case 8 is unusual in that the malig- nant tissues were all adult in type; primitive embryonic elements were not seen. However, the very diversity of elements present makes it difficult to postulate any other histological origin than the Fig. 5 Prominent osseous differentiation surrounded by primitive hepatic blastema, or 'rest' cells derived dense fibrous tissue. H and E x 150. therefrom. Areas of dense, mature, poorly cellular, fibrous Literature review, histological features, and tissue showing necrosis and dystrophic calcification histogenesis of adult mixed hepatoblastoma were prominent in Ludwig's cases and in our tumour. Osteoid may also be seen.313 Extensive calcification copyright. Willis8 has divided hepatoblastoma into embryonic