Periodic ultrasonography checkup for the early detection of pancreatic cancer: preliminary report

Clinical Features and Prognostic Impact of Pancreatic Ductal Adenocarcinoma without Dilatation of the Main Pancreatic Duct: A Single-Center Retrospective Analysis

The presence of main pancreatic duct (MPD) dilatation is important for diagnosing pancreatic ductal adenocarcinomas (PDACs). However, we occasionally encounter PDAC cases without MPD dilatation. The objectives of this study were to compare the clinical findings and prognosis of pathologically diagnosed PDAC cases with and without MPD dilatation and to extract factors related to the prognosis of PDAC. The 281 patients pathologically diagnosed with PDAC were divided into two groups: the dilatation group (n = 215), consisting of patients with MPD dilatation of 3 mm or more, and the non-dilatation group (n = 66), consisting of patients with MPD dilatation less than 3 mm. We found that the non-dilatation group had more cancers in the pancreatic tail, more advanced disease stage, lower resectability, and worse prognoses than the dilatation group. Clinical stage and history of surgery or chemotherapy were identified as significant prognostic factors for PDAC, while tumor location was not. Endoscopic ultrasonography (EUS), diffusion-weighted magnetic resonance imaging (DW-MRI), and contrast-enhanced computed tomography had a high tumor detection rate for PDAC even in the non-dilatation group. Construction of a diagnostic system centered on EUS and DW-MRI is necessary for the early diagnosis of PDAC without MPD dilatation, which can improve its prognosis.

Main pancreatic duct dilatation and pancreatic cysts in relatives and spouses of patients with pancreatic cancer

Although main pancreatic duct dilatation and pancreatic cysts are risk factors for developing pancreatic cancer, limited data exist regarding these findings in relatives and spouses of pancreatic cancer patients. The frequency of these findings was examined using long-term follow-up data and transabdominal ultrasonography focusing on the pancreas. We prospectively enrolled 184 relatives and spouses of pancreatic cancer patients and performed special pancreatic ultrasonography to detect main pancreatic duct dilatation and pancreatic cysts. First-degree relatives (148 participants) of patients with pancreatic cancer were significantly younger than the spouses (36 participants; 41 vs. 65 years old). The frequency of ultrasonographic findings was significantly different between the relative (8.8%) and spouse (33.3%) groups. Main pancreatic duct dilatation and pancreatic cysts were observed in seven (4.7%) and seven (4.7%) participants in the relative group, and in nine (25.0%) and five (13.9%) participants in the spouse group, respectively. On multivariate analysis, age was an independent risk factor for the ultrasonographic findings. The frequency of ultrasonographic findings was significantly higher in spouses than in first-degree relatives of patients with pancreatic cancer and was strongly influenced by the age gap between the groups. Main pancreatic duct dilatation was frequently observed, especially in the spouse group.

Pancreatic Tumorigenesis: Precursors, Genetic Risk Factors and Screening

Pancreatic cancer (PC) is a highly malignant and aggressive tumor. Despite medical advancement, the silent nature of PC results in only 20% of all cases considered resectable at the time of diagnosis. It is projected to become the second leading cause in 2030. Most pancreatic cancer cases are diagnosed in the advanced stages. Such cases are typically unresectable and are associated with a 5-year survival of less than 10%. Although there is no guideline consensus regarding recommendations for screening for pancreatic cancer, early detection has been associated with better outcomes. In addition to continued utilization of imaging and conventional tumor markers, clinicians should be aware of novel testing modalities that may be effective for early detection of pancreatic cancer in individuals with high-risk factors. The pathogenesis of PC is not well understood; however, various modifiable and non-modifiable factors have been implicated in pancreatic oncogenesis. PC detection in the earlier stages is associated with better outcomes; nevertheless, most oncological societies do not recommend universal screening as it may result in a high false-positive rate. Therefore, targeted screening for high-risk individuals represents a reasonable option. In this review, we aimed to summarize the pathogenesis, genetic risk factors, high-risk population, and screening modalities for PC.

Deep learning radiomics based on contrast-enhanced ultrasound images for assisted diagnosis of pancreatic ductal adenocarcinoma and chronic pancreatitis

BACKGROUND

Accurate and non-invasive diagnosis of pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP) can avoid unnecessary puncture and surgery. This study aimed to develop a deep learning radiomics (DLR) model based on contrast-enhanced ultrasound (CEUS) images to assist radiologists in identifying PDAC and CP.

METHODS

Patients with PDAC or CP were retrospectively enrolled from three hospitals. Detailed clinicopathological data were collected for each patient. Diagnoses were confirmed pathologically using biopsy or surgery in all patients. We developed an end-to-end DLR model for diagnosing PDAC and CP using CEUS images. To verify the clinical application value of the DLR model, two rounds of reader studies were performed.

RESULTS

A total of 558 patients with pancreatic lesions were enrolled and were split into the training cohort (n=351), internal validation cohort (n=109), and external validation cohorts 1 (n=50) and 2 (n=48). The DLR model achieved an area under curve (AUC) of 0.986 (95% CI 0.975-0.994), 0.978 (95% CI 0.950-0.996), 0.967 (95% CI 0.917-1.000), and 0.953 (95% CI 0.877-1.000) in the training, internal validation, and external validation cohorts 1 and 2, respectively. The sensitivity and specificity of the DLR model were higher than or comparable to the diagnoses of the five radiologists in the three validation cohorts. With the aid of the DLR model, the diagnostic sensitivity of all radiologists was further improved at the expense of a small or no decrease in specificity in the three validation cohorts.

CONCLUSIONS

The findings of this study suggest that our DLR model can be used as an effective tool to assist radiologists in the diagnosis of PDAC and CP.

Predictive Factors for Pancreatic Cancer and Its Early Detection Using Special Pancreatic Ultrasonography in High-Risk Individuals

Because pancreatic cancer has a dismal prognosis, a strategy for early diagnosis is required. This study aimed to identify predictive factors of neoplastic progression in patients at high risk for pancreatic cancer and examined the efficiency of surveillance using transabdominal special ultrasonography focusing on the pancreas (special pancreatic US). Patients with slight main pancreatic duct (MPD) dilatation (≥2.5 mm) and/or pancreatic cysts (≥5 mm) were enrolled in a prospective surveillance study with special pancreatic US in a Japanese cancer referral center. A total of 498 patients undergoing surveillance for ≥3 years were included. During the median follow-up of 5.9 years, neoplastic progression developed in 11 patients (2.2%), including 9 patients who underwent pancreatectomy. Eight patients (72.7%) were diagnosed with stage 0/I disease, with an overall survival duration of 8.8 years. Findings of both MPD dilatation and pancreatic cysts at initial surveillance, MPD growth (≥0.2 mm/year) and cyst growth (≥2 mm/year) during surveillance were identified as independent risk factors for neoplastic progression. In summary, surveillance with special pancreatic US for high-risk individuals contributed to earlier detection of neoplastic progression, leading to a favorable prognosis. During surveillance, attention should be paid to MPD growth as well as to cyst growth.

How Does Ultrasound Manage Pancreatic Diseases? Ultrasound Findings and Scanning Maneuvers

As ultrasound (US) is simple and less invasive than other imaging modalities, this technique is widely used for mass screening. However, visualizing the entire pancreas due to complicated anatomy, obesity and overlying gas can be difficult. US plays a key role in the diagnosis of pancreatic carcinoma (PC), of which tumors smaller than 10 mm (TS1a) and pancreatic carcinoma <i>in situ</i> are expected to have good prognosis. To detect these forms of PC, main pancreatic duct (MPD) dilatation (3 mm or more) and pancreatic cysts (5 mm or larger) are US findings of high-risk individuals (HRIs), and these subjects should be observed periodically. Scanning maneuvers are also important for both screening for PC and follow-up of HRIs. As lesions in the groove area and ventral pancreas do not affect the MPD or extrahepatic bile duct, we should pay attention to these areas. Visualization of the tail is also challenging due to gas and stool in the alimentary tract. As the position of the pancreas changes depending on the body posture, and several different body positions should be employed, such as the right lateral decubitus, sitting, and upright positions, rather than only applying strong compression with the transducer. In cases with poor visualization, the liquid-filled stomach method is highly recommended.

Effectiveness of Contrast-Enhanced Ultrasonography for the Characterization of Small and Early Stage Pancreatic Adenocarcinoma

The purpose of this retrospective study is to evaluate the effectiveness of contrast-enhanced ultrasonography for the characterization of small and early stage pancreatic adenocarcinoma. Contrast-enhanced ultrasonography and contrast-enhanced computed tomography (CT) were performed in 200 cases, with pancreatic hypoechoic regions detected with ultrasonography. Assuming that hypo-enhancement was indicative of pancreatic adenocarcinoma, the sensitivity of each imaging modality was calculated. The sensitivities of contrast-enhanced ultrasonography and contrast-enhanced CT to characterize adenocarcinoma were 97.0% and 77.0% (p < 0.0001) for all 100 adenocarcinoma cases, 100% and 76.7% (p = 0.0016) for 43 small (≤20 mm) cancers, 100% and 58.3% (p = 0.0253) for 12 smaller (≤10 mm) cancers and 100% and 72.2% (p = 0.0016) for 36 stage IA cancers, respectively. The sensitivity of contrast-enhanced ultrasonography was sufficiently high and significantly superior to that of contrast-enhanced CT. Contrast-enhanced ultrasonography is a sensitive tool for selecting highly possible pancreatic adenocarcinoma lesions without overlooking early stage tiny adenocarcinomas among a large number of hypoechoic lesions detected with ultrasonography.

Ultrasound diagnosis of pancreatic solid tumors

INTRODUCTION

Advances and widespread use of various diagnostic imaging modalities have dramatically improved our ability to visualize and diagnose pancreatic diseases. In particular, ultrasonography in pancreatic diseases plays an important role from screening to diagnosis as a simple and safe examination method.

METHODS

The basic scanning method of transabdominal pancreatic ultrasonography, characterization, and differential diagnosis by ultrasonography including contrast-enhanced ultrasonography (CEUS) for solid pancreatic tumors are reviewed with reference to various papers.

RESULTS

In recent years, the ability to visualize and diagnose pancreatic mass lesions has been dramatically improved with advances in ultrasound equipment. In particular, CEUS using an ultrasound contrast agent has made it possible to evaluate hemodynamics in organs or lesions as well as in the flow signal of arterial blood vessels, and it has played an important role not only in diagnosis of the presence of a lesion but also in the qualitative diagnosis. The enhancement behavior and pattern with CEUS of pancreatic solid tumors is shown in text and Fig. 9. Moreover, the flow chart for diagnosing pancreatic solid tumors with CEUS classifying the enhancement behavior and pattern for pancreatic solid tumors on CEUS is shown (Fig. 10). In meta-analyses, the pooled sensitivity in the differential diagnosis of pancreatic adenocarcinomas and other pancreatic focal masses with CEUS was 86-90%, and the pooled specificity was 75-88%.

CONCLUSION

CEUS is a minimally invasive and useful diagnostic method that can be used to make a simple and quick qualitative diagnosis of pancreatic diseases. CEUS provides a lot of information important for diagnosis, and has led to changes in the conventional diagnostic systems in pancreatic diseases.

The Role of Transabdominal Ultrasound in the Diagnosis of Early Stage Pancreatic Cancer: Review and Single-Center Experience

Pancreatic cancer (PC) is the fourth leading cause of cancer-related death with a 5-year survival rate less than 10%. In the absence of effective screening methods, such as blood markers, most clinical diagnoses of PC are made at an advanced stage. However, early stage PC is associated with a more favorable five-year survival rate of 85.8% for stage 0, and 68.7% for stage IA. Transabdominal ultrasound (US) is frequently used as a first-line diagnostic tool in the clinical setting and a preferred modality for routine medical evaluations for asymptomatic individuals. Recently published Japanese data show that most PCs diagnosed in early stage had US findings, such as dilated main pancreatic ducts or pancreas cysts. For surveillance of high-risk individuals, such as those with an intraductal papillary mucinous neoplasm (IPMN), US is an ideal modality in terms of its non-invasive and cost-effective nature. However, the diagnostic performance of ultrasound varies greatly by the operator’s experience and the patient’s condition. This article reviews the present situation of early diagnosis of pancreatic cancer by US, along with tips for improving visualization of the pancreas.

A case of stage IA pancreatic ductal adenocarcinoma accompanied with focal pancreatitis demonstrated by contrast-enhanced ultrasonography

A patient with slight dilatation of the main pancreatic duct was followed-up with ultrasonography every 6 months as a high-risk case of pancreatic cancer. Twelve years later, a faint hypoechoic area 13 mm in diameter was first detected on the body of the pancreas. Contrast-enhanced ultrasonography revealed a well-demarcated hypoenhanced area 8 mm in diameter and a hyperenhanced area with an unclear margin. The former was suspected to be a small pancreatic cancer lesion, and the latter to be focal pancreatitis accompanying cancer. However, contrast-enhanced dynamic CT did not suggest any tumor, diagnosis of adenocarcinoma was confirmed with pancreatic juice cytology through endoscopic retrograde pancreatography. Surgical resection was performed, and the lesion was pathologically diagnosed as invasive ductal carcinoma as follows: pTS1 (1.0 cm), infiltrative type (pT1), stage IA. When comparing the images from contrast-enhanced ultrasonography with the pathological findings, the hypoenhanced area corresponded to ductal adenocarcinoma, and the hyperenhanced area to focal pancreatitis. Contrast-enhanced ultrasonography was able to reveal detailed information on the focal lesion in the pancreas, and it was effective for the early diagnosis of pancreatic cancer.

Evaluating the ability to detect pancreatic lesions using a special ultrasonography examination focusing on the pancreas

PURPOSE

The ability to detect pancreatic cysts was compared between special ultrasonography (US) examination focusing on the pancreas (special pancreatic US) and routine upper abdominal ultrasonography to objectively assess the ability of the former to detect cysts.

SUBJECTS AND METHODS

Of 3704 patients who underwent special pancreatic US at our hospital, 186 underwent routine upper abdominal US within six months, had pancreatic cysts, and underwent magnetic resonance imaging (MRI). In these patients, 447 cysts measuring ≥5mm were detected via MRI, which was used as the gold standard. The ability and sensitivity of the US modalities to detect each cyst was determined.

RESULTS

The sensitivity of special pancreatic US was 92.2% (95% confidence interval [CI], 89.7%-94.7%) and that of routine upper abdominal US was 70.2% (95% CI, 66.0%-74.5%). McNemar test (Stata Version 13.1) revealed a significant difference in the cyst (≥5mm) detection sensitivity between the two modalities (p<0.001). An analysis stratified by patients similarly revealed a significant difference between the two modalities (p<0.001). The cyst detection sensitivity was also analyzed in various parts of the pancreas. The sensitivity of special pancreatic US was 88.7% for the uncinate process and inferior head, 97.5% for the head, 97.1% for the body, 89.0% for the body-tail, and 66.7% for the tail, whereas that of routine upper abdominal US was 74.2% for the uncinate process, 69.5% for the head, 81.0% for the body, 67.0% for the body-tail, and 26.7% for the tail. The McNemar test revealed significant differences in the sensitivity of the two modalities for all pancreatic parts (p<0.001-0.016).

CONCLUSION

Compared with routine upper abdominal US, special pancreatic US had higher sensitivity in detecting pancreatic cysts.

Pancreatic intraepithelial neoplasia-3 with localized acute pancreatitis in the main pancreatic duct

Pancreatic intraepithelial neoplasia (PanIN) is one of the most important issues for the early detection of pancreatic ductal adenocarcinoma. In particular, PanIN-3 is recognized as a precancerous lesion, e.g., carcinoma in situ, high-grade dysplasia, and severe dysplasia. We report a rare, completely resected case of PanIN-3 in the main pancreatic duct (MPD) detected from localized pancreatitis. A 63-year-old man developed upper abdominal pain with hyperamylasemia. He underwent distal pancreatectomy soon after recovery because an abnormal narrow segment, suggesting PanIN, was identified in the pancreatic body by endoscopic retrograde cholangiopancreatography. Histopathological findings revealed a PanIN-3 located in the MPD that could be resected completely. This finding suggests that if unidentified localized pancreatitis develops, we should carefully examine the fine structural changes in the MPD.

Altered plasma apolipoprotein modifications in patients with pancreatic cancer: protein characterization and multi-institutional validation

Background

Among the more common human malignancies, invasive ductal carcinoma of the pancreas has the worst prognosis. The poor outcome seems to be attributable to difficulty in early detection.

Methods

We compared the plasma protein profiles of 112 pancreatic cancer patients with those of 103 sex- and age-matched healthy controls (Cohort 1) using a newly developed matrix-assisted laser desorption/ionization (oMALDI) QqTOF (quadrupole time-of-flight) mass spectrometry (MS) system.

Results

We found that hemi-truncated apolipoprotein AII dimer (ApoAII-2; 17252 m/z), unglycosylated apolipoprotein CIII (ApoCIII-0; 8766 m/z), and their summed value were significantly decreased in the pancreatic cancer patients [P = 1.36×10⁻²¹, P = 4.35×10⁻¹⁴, and P = 1.83×10⁻²⁴ (Mann-Whitney U-test); area-under-curve values of 0.877, 0.798, and 0.903, respectively]. The significance was further validated in a total of 1099 plasma/serum samples, consisting of 2 retrospective cohorts [Cohort 2 (n = 103) and Cohort 3 (n = 163)] and a prospective cohort [Cohort 4 (n = 833)] collected from 8 medical institutions in Japan and Germany.

Conclusions

We have constructed a robust quantitative MS profiling system and used it to validate alterations of modified apolipoproteins in multiple cohorts of patients with pancreatic cancer.

Pancreatic cancer screening employing noncontrast magnetic resonance imaging combined with ultrasonography

PURPOSE

We have conducted an initial evaluation on the potential of combining noncontrast magnetic resonance imaging (MRI) and ultrasonography (US) to screen for pancreatic cancer.

MATERIALS AND METHODS

An independent ethics committee approved this study. A total of 2511 patients who underwent US were enrolled. Among them, noncontrast MRI was performed in patients in whom the entire pancreas was difficult to depict or in those with US-suspected pancreatic lesions. In total, using 1.5-T MRI, T1- and T2-weighted imaging, magnetic resonance cholangiopancreatography, and diffusion-weighted imaging, we acquired a variety of images. The efficacy of US and MRI in screening for pancreatic lesions, including pancreatic cancer, was evaluated.

RESULTS

Of 2511 patients, 184 underwent MRI, and the pancreas was demonstrated in all of them. Among the 2511, five pancreatic cancers were detected by MRI combined with US (detection rate 0.20%). Of the five pancreatic cancers, three were detected by US (detection rate 0.12%) and two by MRI. Four of the five pancreatic cancers were resectable.

CONCLUSION

By combining noncontrast MRI with US, pancreatic cancer can be detected with high accuracy. Other pancreatic lesions that require follow-up, including intraductal papillary mucinous neoplasms, can also be detected. Thus, pancreatic cancer screening with a combination of US and MRI is suggested.

Slight dilatation of the main pancreatic duct and presence of pancreatic cysts as predictive signs of pancreatic cancer: a prospective study

PURPOSE

To prospectively determine whether slight dilatation of the main pancreatic duct and pancreatic cysts detected at ultrasonography (US) are predictive signs of pancreatic cancer.

MATERIALS AND METHODS

The research protocol was approved by the institutional review board, and written informed consent was obtained from all participants. One thousand fifty-eight subjects (age range, 36-80 years; mean, 61.8 years) with various kinds of abnormal US findings in the pancreas were enrolled from 1999 to 2002, after exclusion of pancreatic neoplasm and other malignant diseases. The endpoint was the subsequent development of pancreatic cancer, and the outcome was determined at the end of December 2007. To identify independent predictive variables for the subsequent development of pancreatic cancer, various baseline characteristics were examined by using a Cox regression model and a Cox proportional hazards model. The cumulative incidence of pancreatic cancer was estimated by using the Kaplan-Meyer method.

RESULTS

During the mean follow-up of 75.5 months (+/- 17.3[standard deviation]), pancreatic cancer subsequently developed in 12 of 1058 subjects. The risk of pancreatic cancer was significantly elevated in subjects with slight dilatation (> or = 2.5 mm) of the main pancreatic duct or presence of cyst (s) (> or = 5 mm). The respective hazard ratios were 6.38 (P = .018) and 6.23 (P = .003). For subjects with both findings, the 5-year cumulative risk of pancreatic cancer was 5.62% (95% confidence interval: .37%, 13.03%), and the age-and sex-adjusted hazard ratio compared with the risk in the absence of these findings was 27.50 (P = .002).

CONCLUSION

Main pancreatic duct dilatation (> or = 2.5 mm) and presence of a pancreatic cyst (> or = 5 mm) were both strong independent predictors of the subsequent development of pancreatic cancer. (c) RSNA, 2010.

Early detection of pancreatic cancer: the Japanese approach

Pancreatic cancer is the fifth leading cause of cancer-related deaths in Japan. Small pancreatic cancers have some abnormal findings on ultrasonography, and diagnosis with endosonography is useful. Positron emission tomography and contrast-enhanced ultrasonography are expected to serve as new modalities for the early detection of pancreatic cancer. The identification of high-risk individuals is necessary to perform efficient screening. Intraductal papillary mucinous neoplasms and chronic pancreatitis are important risk factors for pancreatic cancer.