Residency Program - Case of the Month

Answer:

Anaplastic carcinoma of the pancreas.

The tumor exhibits a biphasic morphology that includes giant cell/multinucleated tumor cells and spindle shaped cells; therefore, this case is subclassified as giant and spindle cell carcinoma type of anaplastic carcinoma of pancreas.

Discussion:

Anaplastic carcinoma is a rare and aggressive tumor with an incidence of 2.1% to 6.8%. Most anaplastic carcinomas are of ductal origin and usually occur at the body or tail of the pancreas. A number of terms have been used to describe variants of undifferentiated carcinoma of the pancreas, including pleomorphic carcinoma, pleomorphic giant cell carcinoma, sarcomatoid carcinoma, spindle cell carcinoma, anaplastic carcinoma, undifferentiated carcinoma and osteoclastic or pleomorphic giant cell tumors. Histologicaly three subtypes have been described for these entity:  spindle cell carcinoma, pleomorphic carcinoma, and round cell carcinoma. Anaplastic carcinoma of the pancreas may have osteoclast like giant cells. These cells are positive for CD68 and lysozyme and negative for epithelial markers. Anaplastic carcinomas of the pancreas with osteoclast like giant cells are very rare and only comprise less than 1% of the pancreatic malignancies.

The pathogenesis of anaplastic carcinoma is unclear. A recent study suggests these neoplasm is of ductal origin and it should be considered an anaplastic variant of pancreatic ductal adenocarcinoma.  Imaging by CT or MRI  is helpful in diagnosing this neoplasm and shows some unique features. In contrast to the uniformly hypoechogenic appearance of typical pancreatic adenocarcinoma, undifferentiated carcinoma of the pancreas tends to be markedly heterogeneous with both well demarcated hyper and hypoechoic areas, closely located within the same lesion.
The prognosis of anaplastic carcinoma of the pancreas is worse than that of poorly differentiated ductal adenocarcinoma of the pancreas. In a study of 35 cases, 29 patients died and the average survival was  5.2 months. The 3-year survival rate of patients with anaplastic carcinoma is less than 3%, with a life expectancy of 10 to 20 months.

No consensus has been made for an optimal chemotherapy.

References:

1. Mitsuyoshi Okazaki, et. al. , A case report of anaplastic carcinoma of the pancreas with remarkable intraductal tumor growth into the main pancreatic duct, World J Gastroenterol 2014 January 21; 20(3): 852-856
   
   
2. Michimasa Fujiogi, Anaplastic Carcinoma of the Pancreas Mimicking Submucosal Gastric Tumor: A Case Report of a Rare Tumor, Hindawi Publishing Corporation Case Reports in Medicine Volume 2013, Article ID 523237
   
   
3. Manpreet K Chadha, Anaplastic Pancreatic Carcinoma.  A Case Report and Review of Literature, JOP. J Pancreas (Online) 2004; 5(6):512-515.