Sarcomatoid carcinoma of the pancreas with rare long-term survival: a case report

Abstract

Background: Sarcomatoid carcinoma of the pancreas (SCP) tends to have similar or even worse prognosis than that of conventional pancreatic ductal adenocarcinoma. The clinical and pathological features of SCP remain poorly characterized owing to its rarity.

Case presentation: A 58-year-old man was admitted to our hospital with the chief complaints of upper abdominal pain and weight loss. Abdominal contrast computed tomography revealed a 5-cm low-density mass in the pancreatic body. Magnetic resonance cholangiopancreatography revealed an obstruction of the main pancreatic duct and a dilation of the distal main pancreatic duct. Based on the clinicoradiological findings, pancreatic body cancer was suspected, and the distal pancreatectomy was performed. A pathological examination revealed that the tumor was composed of an area of invasive ductal adenocarcinoma and an area of sarcomatous spindle-shaped cells; the latter component predominated. The spindle cells were immunohistochemically positive for both cytokeratin and vimentin, and thus, a pathological diagnosis of SCP was made. In addition, immunohistochemical analysis suggested the sarcomatous component might be derived from the adenocarcinoma component via the process of epithelial-mesenchymal transition. After the operation, the patient received 6 months of chemotherapy with gemcitabine. At 10 years after the operation, the patient is alive with no recurrence.

Conclusions: The current case study presented a SCP patient with long-term survival after the operation. It was worth noting that the sarcomatous component of the tumor pathologically showed lower MIB-1 labeling index compared with those in previously reported SCP cases, which might account for the long-term survival of the patient.

Keywords: Epithelial-mesenchymal transition; Long-term survival; Pancreatic cancer; Sarcomatoid carcinoma.

Fig. 1

Contrast-enhanced CT scan (early phase) showed a low-density mass measuring 5 cm in diameter in the pancreatic body (arrows) (a). Contrast-enhanced CT scan (late phase) (b). MRI showed a tumor in the pancreatic body showing low intensity on T1-weighted images (c) and relatively high intensity on T2-weighted images (d). MRCP revealed a dilation of the distal main pancreatic duct (arrows) (e)

Fig. 2

Pathological findings. An ill-defined infiltrative tumor was grossly observed in the pancreatic body (a). Histologically, the tumor was composed an area of adenocarcinoma (b) and sarcomatous spindle cells (c). A transition was observed between the adenocarcinoma component and the sarcomatous component (d). The lumen of the main pancreatic duct (MPD) within the tumor was covered by high-grade pancreatic intraepithelial neoplasia (e). Arrowheads indicate retention cysts

Fig. 3

Immunohistochemical findings. The adenocarcinoma component was reactive to an antibody against cytokeratin (AE1/AE3). The sarcomatous component was reactive to antibodies against both cytokeratin and vimentin

Fig. 4

Immunostaining of Ki67. The MIB-1 labeling index was 38% in the adenocarcinoma component and 11% in the sarcomatous component

Fig. 5

Immunohistochemical expression of EMT-related molecules. The expression of pSmad2/3 was observed in the nuclei of both the adenocarcinoma and sarcomatous components, whereas Snail and fibronectin were preferentially expressed in the sarcomatous component