Pancreatic adenocarcinoma is an uncommon type of cancer, which accounts for no more than 3.2% of all new cancer cases based on the latest SEER data. However, it is a highly aggressive tumor, ranking very high as a cause of cancer-related deaths. It is the fourth leading cause of cancer death among men and women . The overall 5-year survival rate is no more than 8.2% and is barely 2% for patients with advanced disease at presentation. These low survival rates are due to the aggressive nature of the tumor in most patient present with advanced stage disease who have little, if any, chance of cure despite aggressive treatment. Chances for improved survival depend on achieving complete surgical resection, although this cannot be performed in more than 80% of the cases who already have advanced or metastatic disease at presentation . Given the low incidence of this malignancy and the complexity of management, particularly related to the morbidity and mortality from the challenging surgical resection, the National Cancer Network Guidelines for Pancreatic Adenocarcinoma recommends that decisions about management, and whether surgical resection can be pursued, should involve multidisciplinary consultation at high-volume centers with an emphasis on the use of appropriate imaging studies . Bilimoria et al. have shown that patients who underwent surgical resection at low-volume centers are more likely to have margin-positive resections leading to poor survival rates that are comparable to patients who did not undergo resection . For these reasons, most patients diagnosed with pancreatic adenocarcinoma in smaller hospitals or imaging centers are referred to a tertiary center with a dedicated oncology program that deals with a high volume of patients with pancreatic cancer.
Unlike many other cancers, cross-sectional imaging remains the primary modality to accurately diagnose the stage of pancreatic cancer, particularly the relationship of the tumor to the peripancreatic vessels, which is a major determinant of the possibility of surgical resection in the absence of distant metastasis. Typically, patients referred to the tertiary centers have already had imaging performed that led to the diagnosis and initiation of the referral. However, these examinations are often protocoled and interpreted by general radiologists who lack sufficient experience in imaging these uncommon tumors. This often leads to incomplete reporting of the pertinent imaging findings needed to accurately stage the tumor. In our experience, patients considered resectable based on the available report may have vascular tumor contact or even subtle metastatic deposits that were not recognized and were found at reinterpretation by a subspecialty radiologist, who has experience in oncologic imaging, leading to change in management. Accurate staging of the disease will ensure that patients with favorable stage (resectable or borderline resectable) are offered potentially curative surgery without delay while sparing accurately identified patients with locally advanced or metastatic disease unnecessary surgery.
At the time of intense scrutiny of all health-care costs, it is relevant to ensure that every action taken in patient management has a positive impact that would justify the associated cost. Whether reinterpretation of these examinations by subspecialty radiologists would affect patient management and whether the added costs associated with that reinterpretation is justified is the subject of the accompanying study by Corrias et al. in this edition of Academic Radiology . The authors attempted to answer the first relevant question that is whether or not reinterpretation of outside imaging studies performed on patients referred to the pancreatic multidisciplinary clinic impacts patient management. They retrospectively compared 65 individual patients original imaging interpretation to the reinterpretation provided by subspecialized abdominal radiologist to assess if the reinterpretation added value by potentially changing patient management. The theoretical effect on management was assessed based on evaluation of the presented data in the imaging reports by two blinded experienced surgeons. The authors show a theoretical positive impact on patient care based on these reinterpretations with discrepancies in 32 of 65 patients (49.2%) between the original and reinterpreted examinations that could potentially affect the patient management. In their cohort, cancer staging changed in 13% to 18.4% of cases based on the opinions provided by the two surgeons respectively when evaluating the reinterpreted examinations. This resulted in a change in patient management in more than 20% to 38.4% for the respective surgeons. When compared with the reference pathologic staging gold standard, second opinion was correct in 85.7% of the time for both surgeons. There was good agreement between the surgeon decision and the actual patients’ outcome (kappa of more than 0.6). There was a greater chance to upgrade the stage of the disease, commonly due to either underestimation of the local extent of the tumor or unreported metastatic sites, especially to the peritoneum, where metastases are frequently difficult to detect. The greatest effect was reported in the change of therapy from surgery to chemotherapy in 9.2%–23.1% of cases. Downgrading the tumor stage was uncommon with a change of therapy from chemotherapy to potential curative surgery reported in no more than 0%–6.1% of cases.
Reinterpretation of the outside imaging studies by experienced subspecialty radiologists can also add value in several other ways, including:
- Ensuring that the referral is appropriate and there is no alternative diagnosis that could explain the imaging findings. One common example is autoimmune pancreatitis mimicking pancreatic cancer .
- Avoiding unnecessary repeated examinations by checking that the imaging quality of the examination is adequate and can answer the clinical question to complete the staging. It should be stressed, however, that the presence of an outside imaging study should not by itself deter a repeat examination at the referral institution if the original examination is suboptimal. One of the most common deficiencies of the pancreas outside computed tomography examinations is the absence of an optimally timed computed tomography angiographic examination of the pancreas in both arterial and portal venous phases .
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