Hepatoblastoma is an exceptionally rare malignancy in adults with just over 70 non-pediatric cases reported in literature. Recounted is a case of a 49-year-old female who presented with acute right upper quadrant abdominal pain, elevated serum alpha fetoprotein and a large liver mass on imaging. Hepatectomy was performed under clinical suspicion of hepatocellular carcinoma. Immunomorphologic characteristics of the tumor proved consistent with hepatoblastoma of mixed epithelial and mesenchymal type. Hepatocellular carcinoma remains to be the primary differential diagnosis for adult hepatoblastoma, however, distinguishing between these two neoplasms requires close histomorphologic assessment and immunohistochemical profiling as clinical, radiologic and gross pathologic findings typically overlap. Making this distinction is highly crucial in the timely initiation of surgical and chemotherapeutic interventions for this inherently aggressive and rapidly fatal disease.

Tubulocystic renal cell carcinoma (TC-RCC) is a recently recognized, rare but distinct malignant entity. Pathologists have endeavored to completely define its histomorphologic, immunohistochemical and molecular features. Recounted is a case where the diagnosis of TC-RCC was confounded by presence of papillary morphology. Immunohistochemical expression of alpha-methyl acyl-CoA-racemase and vimentin with corresponding negativity for CK7 and CD10, following distinctive gross and microscopic findings, confirmed a diagnosis of TC-RCC. This report demonstrates the strategic value of performing immunohistochemistry studies to establish a diagnosis of TC-RCC especially when unusual histologic features are encountered. Immunohistochemistry continues to be the most practical approach to diagnosis as molecular testing methods, such as next generation sequencing, remain unfeasible in the local setting. Cautious prognostication is required as accounts of recurrence and metastasis continue to emerge.
Carcinoma, Renal Cell ; Histology ; Immunohistochemistry ; Diagnosis ; Pathology, Surgical