Clinical diagnosis
Case 200
【Progress】
Case 1: He received surgical resection of pancreas tail whose histologic specimen revealed early pancreas cancer. He has been surviving and healthy for one year and a half.
Case 2: He was diagnosed advanced pancreatic cancer with no indication of surgical resection. Then, his main treatment was chemotherapy with GEM alone. Six months later, the effect of GEM on the tumor was progressive disease.
【Discussion】
The pancreas is anatomically categorized into head, body and tail: superior mesenteric vein is the border between head and body while inferior mesenteric vein, between body and tail. Following lung cancer, colon cancer and stomach cancer, pancreas cancer is the 4th place for cancer death numbers: approximate 36000/year in Japan. The nearly 40000 patients with pancreas cancer emerge every year (1). The five year survival rate is less than 10 % (2). Typical symptoms of pancreatic cancer are backpain, icterus, weight loss and diabetes. Prognosis is better for patients with pancreas head cancer than with pancreas body & tail cancer because head cancer is apt to be found earlier than body-tail cancer due to the earlier symptom emergence such as icterus (3, 4). Further, even if in the same stage of TNM, the survival is poorer in body-tail cancer than head cancer. Surgical pancreas resection is conducted in 15% of all patients with pancreas cancer (2-4). Gemcitabine is reported to extend life time longer than other anticancer drugs for nonresectable pancreas cancer which is becoming a standard chemotherapy (2). At any rate, it is crucial to find the localized pancreas cancer for elevating survival rate.
One of the current keys to overcome pancreatic cancer is to find the early- stage pancreatic cancer. The laboratory test with CEA (< 5.0 ng/dL) and CA19-9 (< 37 U/mL) might contribute to find localized pancreatic cancer. The survival rate is more favorable in pancreatic cancer patients with less than CEA less than 15 ng/dL and /or CA19-9 less than 370 U/mL (5, 6). Pancreatic cancer causes the higher values of CEA and CA19-9 with its advances. Abdominal ultrasound is useful for some slender people whose whole pancreas can be detectable but not for some obesity people. It is reported that dilatation of pancreatic duct on ultrasound is the crucial finding for early-stage pancreatic cancer. In Case1with CEA 29.6 ng/dL and CA19-9 251 U/mL, fortunately, abdominal ultrasound showed low echoic area in the pancreas tail, although no pancreatic dilatation was found. Meanwhile, in Case 2 with CEA 5.5 ng/dL and CA19-9 1402 U/mL, CT showed pancreatic body-tail cancer with peri-celiac and peri-SMA involvement, indicating to be unresectable.
Abdominal computed tomography (CT) is also useful to detect pancreatic duct dilatation and biliary duct dilatation. But abdominal non-enhanced CT is hard to detect early-stage pancreatic cancer itself simply because the density of pancreas cancer is almost the same as pancreatic parenchyma (Figs 1, 2). Further, detectability of the early-stage pancreatic cancer on dynamic CT with contrast medium is not always favorable: hard to detect on the delayed phase and on the portal phase, but possibly useful to detect it as low density on arterial phase (Figs 1, 2). In this situation, it is problematic to differentiate early-stage pancreas cancer from mass-forming pancreatitis. Meanwhile, the detectability for advanced pancreatic cancer is not so difficult irrespective of non-enhanced CT or enhanced CT with contrast medium (Figs 3, 4).
Abdominal MRI and MRCP is feasible to detect the early-stage pancreas cancer by demonstrating the dilatation of pancreatic duct and tumor itself. Further, MRI with diffusion weighted imaging is useful to differentiate early pancreas cancer (malignant lesion) from mass-forming pancreatitis (benign lesion).
【Summary】
We present two cases with pancreatic body-tail cancer: localized and advanced. Dynamic CT with contrast medium showed a lesion with low density area only on arterial phase but hard to identify it on portal and delayed phases. It is borne in mind that to find the localized pancreatic cancer with CEA less than 15 ng/dL and /or CA19-9 less than 370 U/mL on ultrasound, on arterial phase, on enhanced CT with contrast medium or abdominal MRI with diffusion WI. Pancreas cancer prognosis is the 4th place following lung cancer, colon cancer and stomach cancer. The 5-year survival is less than 10% and surgical resection rate is 15%, indicating most patients when discovered, too late for surgical indication.
【References】
1.Cancer statistic prediction in Japan 2019 https://ganjoho.jp/reg_stat/statistics/stat/short_pred.html
2.Okusaka T, et al. Clinical practice guidelines for pancreatic cancer 2019 from the Japan pancreas society: a synopsis. . 2020;49:326-335.
3.Birnbaum DJ, et al. Head and Body/Tail Pancreatic Carcinomas Are Not the Same Tumors. Cancers 2019; 11: 497
4.Artinyan A, et al. The anatomic location of pancreatic cancer is a prognostic factor for survival. HPB (Oxford). 2008; 10: 371–376.
5.Lundin J, et al. The Prognostic Value of Preoperative Serum Levels of CA 19-9 and CEA in Patients With Pancreatic Cancer. Br J Cancer 1994;69:515-9.
6.van Manen L, et al. Elevated CEA and CA19-9 Serum Levels Independently Predict Advanced Pancreatic Cancer at Diagnosis. Biomarkers 2020;25:186-193
2020.8.5