1999 Volume 38 Issue 6 Pages 540-546
Background: Since adenocarcinoma with hepatoid transformation is relatively rare, there have been few case reports with cytological analysis of the tumor in the literature. We report the cytological features of an autopsy case of welldifferentiated tubular adenocarcinoma of the sigmoid colon showing hepatoid differentiation in metastatic lesions.Case: A 60-year-old man received sigmoidectomy for sigmoid colon cancer 4 years ago. Histopathological examination of the primary tumor revealed well-differentiated tubular adenocarcinoma without hepatoid differentiation. Two years after initial surgery, a metastatic lesion developed in the liver and was resected. Histopathological diagnosis was tubular adenocarcinoma. He was admitted to Kumamoto University Hospital because of tumor metastasis in the thoracic wall 3 years after initial surgical treatment. At admission, laboratory examination revealed an extremely high elevation of serum α-fetoprotein (AFP) levels. After admission, intensive chemotherapy was performed; however, the patient died of respiratory failure with multiple pulmonary metastases.At autopsy, multiple cancer metastases were found in the thoracic wall, lungs, bone, mediastinal lymph nodes, liver, and spleen. Imprint cytology revealed two different types of malignant cells; one was high columnar cancer cells with enlarged nucleoli, suggesting the features of well-differentiated adenocatcinoma, and the other was composed of cancer cells resembling the cytological features of hepatocellular carcinoma with loose clusters or a solid-sheet arrangement and with light-green-positive hyaline globules in the cytoplasm. Histopathologically, the metastatic lesions were composed of two different types of cells; The major component was medullarly-grown cancer cells with hepatoid cell characteristics, and the minor was well-differentiated tubular adenocarcinoma. Immunohistochemically, the primary carcinoma of the sigmoid colon was only positive for carcinoembryonic antigen (CEA), while the major component of the cancer cells in the metastatic lesions were positive for AFP, CEA, neuron-specific enolase, chromogranin A, human chorionic gonadotropin, α-1-antitrypsin, α-1-antichymotrypsin, transthyretin and keratin.Conclution: Cytological characteristics of cancer cells in the metastatic lesion are useful for making an accurate cytological diagnosis of adenocarcinoma with hepatoid differentiation.
