Early diagnosis of pancreatic cancer: Shedding light on an unresolved challenge

Abstract

Diagnosing early-stage pancreatic cancer (PC) remains a clinical challenge. Hence, studying novel imaging aspects that could enhance the diagnostic accuracy of malignant pancreatic precursor lesions is imperative. This article aims to underscore the promising role of emerging imaging aspects that may facilitate the earlier diagnosis of PC, thereby improving its management and prognosis.

Key Words: Pancreatic cancer; Pancreatic intraepithelial neoplasm; High-grade pancreatic intraepithelial neoplasm; Pancreatic ducts; Cancer; Early diagnosis

Core Tip: The description and validation of novel imaging findings that could enhance the diagnosis of pancreatic cancer (PC) at early stages remain a challenge for radiologists. However, recent studies have suggested emerging radiological signs that may facilitate the early diagnosis of PC and its malignant precursor lesions.

TO THE EDITOR

In their recent article titled “High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings: A case report”, Furuya et al[1] reported and described the pre-operative diagnosis and surgical treatment of high-grade pancreatic intraepithelial neoplasia (PanIN) based on the evaluation of indirect imaging findings and their evolution over time. I commend this novel and intriguing report, which may contribute to emerging insights into imaging aspects relevant to the early diagnosis of pancreatic cancer (PC).

According to the Globocan observatory database, PC ranks as the fifth most common gastrointestinal malignancy and the seventh leading cause of global cancer deaths[2]. Nevertheless, current epidemiological studies over the past decade have consistently reported an increasing trend in both its incidence and mortality rates[3,4]. Given that many patients are diagnosed at advanced stages due to the absence of specific symptoms, the detection of PC heavily relies on imaging studies. However, despite continuous advancements in abdominal imaging techniques, accurately detecting PC at early stages remains challenging[5,6].

At present, approximately 50% of patients present with locally advanced or distant metastatic disease at the time of diagnosis, resulting in a 5-year survival rate ranging from 3% to 15%[7]. Notably, the poor survival rate observed in pancreatic PC is attributed not only to its extremely aggressive biological behavior but also to the challenges in achieving accurate diagnosis during the early stages[8,9]. Therefore, it is imperative to further investigate diagnostic findings that enable suspicion and detection of early-stage PC.

High-grade PanIN is a type of preneoplastic lesion originating from pancreatic ducts, characterized by low-papillary progression, and considered a potentially curable stage of PC[10]. However, the absence of specific imaging findings suggesting the diagnosis of high-grade PanIN complicates the detection of this intra-epithelial malignant lesion, which is primarily detectable only under a microscope. Consequently, the emergent description and development of indirect radiological features that may allow for the detection of high-grade PanIN could play a promising role in the early diagnosis of PC[11].

An observational and retrospective multicenter study conducted by the Japan Study Group on the Early Detection of Pancreatic Cancer[12] examined the clinical, imaging, and pathological features of 200 patients with early-stage PC. The study suggested that the evaluation of several findings on ultrasound, computed tomography (CT), and magnetic resonance imaging, such as main pancreatic duct (MPD) dilation, MPD stenosis, focal pancreatic parenchymal atrophy, and local fatty changes, could be useful for detecting early-stage PC.

Another interesting study recently published by Toshima et al[13] also aims to investigate indirect imaging findings that could be useful in detecting early-stage PC. In this study, the authors analyzed CT examinations conducted before the diagnosis of PC, revealing that 53.4% of patients with early-stage PC exhibited focal pancreatic abnormalities at least 1 year before diagnosis. These abnormalities included focal pancreatic atrophy, faint focal enhancement, and focal changes in the MPD. These findings may represent secondary structural changes in the ductal parenchyma underlying prolonged disease progression among malignant precursor lesions and progressive early tumoral desmoplasia.

In summary, the accurate diagnosis of PC in early stages remains a challenge for radiologists. Continuous research into emerging imaging aspects that could be useful for diagnosing early PC is imperative. In this context, the study published by Furuya et al[1] sheds light on this unresolved challenge, highlighting emerging aspects that could facilitate earlier diagnosis of PC, thereby improving management and prognosis.