Clinical Analysis of Early-Stage Pancreatic Cancer and Proposal for a New Diagnostic Algorithm: A Multicenter Observational Study

Abstract

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is challenging but essential for improving its poor prognosis. We established a multicenter study to clarify the clinicopathological features, and to propose new algorithm for early diagnosis of PDAC. Ninety-six patients with stage 0 and IA PDAC were enrolled from 13 high-volume centers. Overall, 70% of the patients were asymptomatic. The serum pancreatic enzyme levels were abnormal in half of the patients. The sensitivity of endoscopic ultrasonography (EUS) for detecting small PDAC was superior to computed tomography and magnetic resonance imaging (MRI) (82%, 58%, and 38%, respectively). Indirect imaging findings were useful to detect early-stage PDAC; especially, main pancreatic duct stenosis on MRI had the highest positive rate of 86% in stage 0 patients. For preoperative pathological diagnosis, the sensitivity of endoscopic retrograde cholangiopancreatography (ERCP)-associated pancreatic juice cytology was 84%. Among the stage IA patients, EUS-guided fine-needle aspiration revealed adenocarcinoma in 93% patients. For early diagnosis of PDAC, it is essential to identify asymptomatic patients and ensure close examinations of indirect imaging findings and standardization of preoperative pathological diagnosis. Therefore, a new diagnostic algorithm based on tumor size and imaging findings should be developed.

Clinical features and prognostic impact of asymptomatic pancreatic cancer

“…In asymptomatic patients with PDAC, CT initially detected abnormalities in 37.1%, US in 34.6%, and blood test results in 16.1%, which in total accounted for 87.8% of all cases. These figures are similar to those of previous studies from Japan 11 , 25 , but different from those reported in Western countries, where asymptomatic cases have been found mainly using CT 9 , 26 . Bruzoni et al 26 reported that 89% of pancreatic incidentalomas were detected using CT.…”

Analysis of Progression Time in Pancreatic Cancer including Carcinoma In Situ Based on Magnetic Resonance Cholangiopancreatography Findings

“…Previous studies have reported very low numbers of patients with PC and pancreatic calcification (0-5.3%) [22][23][24]; therefore, caution is needed when diagnosing patients with MPD stenosis without pancreatic calcification or tumor lesions. In this regard, recent studies have reported that an assessment of partial pancreatic parenchymal atrophy around small PCs is very useful for the diagnosis of small PCs [23][24][25][26][27][28]. Indeed, partial parenchymal atrophy was detected in our study patients with 14 mm and 36 mm lesions (Cases 5 and 9 in Supplementary Table S1) on the initial CT; therefore, the presence of partial pancreatic parenchymal atrophy could be a significant finding suggestive of PC.…”

Diagnostic Strategy of Early Stage Pancreatic Cancer via Clinical Predictor Assessment: Clinical Indicators, Risk Factors and Imaging Findings

“…Most of the factors mentioned above are mainly analyzed in patients with advanced PDAC, but the data on early stage PDAC are insufficient [ 15 , 26 ]. In this study, a more effective method for early stage PDAC detection was considered, and new categories of clinical indicators and risk factors were compared in patients with and without early stage PDAC.…”

“…On the other hand, risk factors included sporadic family history of pancreatic cancer, familial pancreatic cancer, hereditary pancreatic cancer syndrome/hereditary pancreatitis, DM, chronic pancreatitis, heavy alcohol consumption, smoking history, and obesity [ 5 , 21 , 22 , 23 , 24 ]. Imaging findings included the tumor itself and indirect imaging findings (MPD dilation, pancreatic cyst, and IPMN) [ 11 , 14 , 16 , 17 , 25 , 26 , 27 , 28 , 29 ].…”

“…These factors have been suggested as suggestive of early stage PDAC detection in many guidelines and reviews [5,11,14,21,22,24]. These three new categories and previously reported percentage of each factor in patients with stage 0-Ⅰ PDAC is shown in Figure 1 and Table 1 [15,26]. In each category, each factor, the presence or absence of factors, and the number of factors were evaluated.…”