Metastatic neoplasms to the pancreas diagnosed by fine-needle aspiration/biopsy cytology: A 15-year retrospective analysis

Metastatic Neuroendocrine Neoplasms to the Pancreas: Two Unusual Cases and a Review of the Literature

Neuroendocrine tumor metastases to the pancreas are rare, and they share substantial overlap with the significantly more common primary pancreatic neuroendocrine neoplasms, representing a potential diagnostic pitfall. Elucidating whether a neuroendocrine tumor within the pancreas is a primary neoplasm versus a metastasis has significant prognostic and treatment implications. Correlation with clinical history and imaging as well as incorporating an appropriate immunohistochemical panel are essential to establish the correct diagnosis. Herein, we present 2 rare neuroendocrine tumors that metastasized to the pancreas: a medullary thyroid carcinoma and an atypical carcinoid tumor of lung origin. We also provide a brief review of the literature.

Challenges and Pitfalls in Pancreatobiliary Cytopathology

INTRODUCTION

The advances of minimally invasive endoscopy-guided procedures that usually yield limited diagnostic material changed pancreaticobiliary cytopathology into one of the most challenging areas of cytopathology given the abundance of differential diagnoses to be considered when dealing with limited specimens.

CASE PRESENTATION

We describe a few challenging examples of potential pitfalls in pancreatobiliary cytopathology evaluation collected from a busy academic hospital (tertiary) center. Case 1 illustrates the challenges in handling paucicellular specimens from pancreatic solid lesions in which differential diagnoses may include acinar cell carcinoma, neuroendocrine tumors, adenocarcinoma, or even benign pancreatic tissue, among others. Case 2 illustrates the pitfalls in evaluating limited specimens from patients with chronic pancreatitis, specially when distinguishing exuberant reactive atypia from dysplastic changes is mandatory. Case 3 illustrates pitfalls in distinguishing malignancy from reactive changes in biliary brushing specimens from patients with primary sclerosing cholangitis. Finally, cases 4 and 5 highlight the importance of including the possibility of pancreatic metastasis in the differential diagnoses of some pancreatic lesions.

CONCLUSION

Over time, there has been an increasing demand for pathologists to render diagnoses on limited specimens obtained through minimally invasive procedures which can be frequently challenging even for the most experienced professionals. In many difficult cases, salvaging additional material for a cell block can turn out to be extremely helpful given the possibility of utilizing additional ancillary tests for diagnostic confirmation.

Comments on and Illustrations of the EFSUMB CEUS Guidelines: Transabdominal and Endoscopic Ultrasound Features of Intrapancreatic Metastases and the Role of Multiparametric Imaging and EUS-Guided Sampling in Rare Pancreatic Tumors

A definite pathologic diagnosis of intrapancreatic metastasis is crucial for the management decision, i.e., curative or palliative surgery versus chemotherapy or conservative/palliative therapy. This review focuses on the appearance of intrapancreatic metastases on native and contrast-enhanced transabdominal ultrasound and endoscopic ultrasound. Differences and similarities in relation to the primary tumor, and the differential diagnosis from pancreatic carcinoma and neuroendocrine neoplasms are described. The frequency of intrapancreatic metastases in autopsy studies and surgical resection studies will be discussed. Further emphasis is placed on endoscopic ultrasound-guided sampling to confirm the diagnosis.

A nomogram diagnostic prediction model of pancreatic metastases of small cell lung carcinoma based on clinical characteristics, radiological features and biomarkers

Objective

To investigate clinical characteristics, radiological features and biomarkers of pancreatic metastases of small cell lung carcinoma (PM-SCLC), and establish a convenient nomogram diagnostic predictive model to differentiate PM-SCLC from pancreatic ductal adenocarcinomas (PDAC) preoperatively.

Methods

A total of 299 patients with meeting the criteria (PM-SCLC n=93; PDAC n=206) from January 2016 to March 2022 were retrospectively analyzed, including 249 patients from hospital 1 (training/internal validation cohort) and 50 patients from hospital 2 (external validation cohort). We searched for meaningful clinical characteristics, radiological features and biomarkers and determined the predictors through multivariable logistic regression analysis. Three models: clinical model, CT imaging model, and combined model, were developed for the diagnosis and prediction of PM-SCLC. Nomogram was constructed based on independent predictors. The receiver operating curve was undertaken to estimate the discrimination.

Results

Six independent predictors for PM-SCLC diagnosis in multivariate logistic regression analysis, including clinical symptoms, CA199, tumor size, parenchymal atrophy, vascular involvement and enhancement type. The nomogram diagnostic predictive model based on these six independent predictors showed the best performance, achieved the AUCs of the training cohort (n = 174), internal validation cohort (n = 75) and external validation cohort (n = 50) were 0.950 (95%CI, 0.917-0.976), 0.928 (95%CI, 0.873-0.971) and 0.976 (95%CI, 0.944-1.00) respectively. The model achieved 94.50% sensitivity, 83.20% specificity, 86.80% accuracy in the training cohort and 100.00% sensitivity, 80.40% specificity, 86.70% accuracy in the internal validation cohort and 100.00% sensitivity, 88.90% specificity, 87.50% accuracy in the external validation cohort.

Conclusion

We proposed a noninvasive and convenient nomogram diagnostic predictive model based on clinical characteristics, radiological features and biomarkers to preoperatively differentiate PM-SCLC from PDAC.

An exceptionally rare case of metastatic high-grade urothelial carcinoma of the renal pelvis to the pancreas diagnosed on endoscopic ultrasound-guided fine-needle aspiration: A diagnostic challenge

Metastases to the pancreas are rare and can be confused with the primary adenocarcinoma of the pancreas. Metastasis of renal pelvis urothelial carcinomas to the pancreas are extremely rare. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy is a very safe and effective diagnostic method. In this study, we present a 65-year-old male patient with a solitary mass in the pancreas. A moderate cellular tumoral lesion was observed in the aspiration cytology performed from the 55-millimeter solid mass invading the head of the pancreas via EUS-FNA. Tumor cells consisted of cells with irregular borders, different shapes and sizes, hyperchromatic, narrow cytoplasm with dark nuclei, and cells with anisonucleosis in focal areas. Cellblock obtained from aspirated was found diffusely positive with high molecular weight cytokeratin, Thrombomodulin, p63, GATA-3, and CK7, and negative with CK20, PAX8, and PSA. Having a primary malignancy in the medical history of the patients is very important in the differential diagnosis of primary and secondary pancreatic cancers. The potential for metastasectomy in pancreatic metastases can be applied in cases with isolated metastatic disease. Primary tumor histopathology may have an impact on the long-term survival of the case. This study aimed to describe the cytomorphological features of solid and solitary pancreatic malignancies and to evaluate the role of immunohistochemistry performed from aspirate cell block in detecting the primary tumor origin.

Malignant biliary obstruction due to metastatic non-hepato-pancreato-biliary cancer

Malignant biliary obstruction generally results from primary malignancies of the pancreatic head, bile duct, gallbladder, liver, and ampulla of Vater. Metastatic lesions from other primaries to these organs or nearby lymph nodes are rarer causes of biliary obstruction. The most common primaries include renal cancer, lung cancer, gastric cancer, colorectal cancer, breast cancer, lymphoma, and melanoma. They may be difficult to differentiate from primary hepato-pancreato-biliary cancer based on imaging studies, or even on biopsy. There is also no consensus on the optimal method of treatment, including the feasibility and effectiveness of endoscopic intervention or surgery. A thorough review of the literature on pancreato-biliary metastases and malignant biliary obstruction due to metastatic non-hepato-pancreato-biliary cancer is presented. The diagnostic modality and clinical characteristics may differ significantly depending on the type of primary cancer. Different primaries also cause malignant biliary obstruction in different ways, including direct invasion, pancreatic or biliary metastasis, hilar lymph node metastasis, liver metastasis, and peritoneal carcinomatosis. Metastasectomy may hold promise for some types of pancreato-biliary metastases. This review aims to elucidate the current knowledge in this area, which has received sparse attention in the past. The aging population, advances in diagnostic imaging, and improved treatment options may lead to an increase in these rare occurrences going forward.

Metastatic tumors to the pancreas: Balancing clinical impression with cytology findings

Backgrounds/Aims

Metastatic lesions of the pancreas (PMET) account for 1%–5% of all malignant solid pancreatic lesions (SPL). In this study we evaluated the utility of endoscopic ultrasonography with fine needle aspiration (EUS-FNA) in diagnosing PMET.

Methods

Patients who underwent EUS-FNA at a community referral center between 2011–2017 for SPL were identified. Clinical, radiologic, and EUS-FNA features of those with PMET were compared to those with primary solid tumors of the pancreas: pancreatic adenocarcinoma (PDAC) and neuroendocrine tumors (PNET).

Results

A total of 191 patients were diagnosed with solid pancreatic malignancy using EUS-FNA: 156 PDAC, 27 PNET, and eight (4.2%) had PMET. Patients with PMET were less likely to have abdominal pain (25.0% vs. 76.3% vs. 48.2%; p < 0.01) or obstructive jaundice (37.5% vs. 58.3% vs. 0%; p < 0.01) compared to PDAC and PNET. Those with PMET were more likely to have mass lesions with/without biliary or pancreatic ductal dilatations (100% vs. 86.5% vs. 85.2%; p < 0.01) and lower CA19-9 (82.5 ± 43.21 U/mL vs. 4,639.30 ± 11,489.68 U/mL vs. 10.50 ± 10.89 U/mL; p < 0.01) compared to PDAC and PNET. Endosonographic features were similar among all groups. Seven (87.5%) patients with PMET had a personal history of malignancy prior to PMET diagnosis. The primary malignancy was renal cell carcinoma in five PMET.

Conclusions

PMET are exceedingly rare, comprising less than 5% of SLP. Patients with PMET are less likely to present with symptoms and mostly identified by surveillance imaging for the primary malignancy.

Clinical practice guidelines for the interventional treatment of advanced pancreatic cancer (5th edition)

Pancreatic cancer has become a major disease affecting people's health because of its insidiousness, rapid progression and poor prognosis. Based on the practical needs of clinical work, combined with domestic multi-center research and experience, this guideline provides constructive suggestions for the interventional treatment of pancreatic cancer.

Merkel Cell Carcinoma With Isolated Pancreatic Metastasis

Merkel cell carcinoma (MCC) is a highly aggressive cutaneous neuroendocrine carcinoma, frequently associated with distant metastasis. However, recurrence of MCC manifesting with only pancreatic involvement is exceedingly rare. A 53-year-old man presented to our institution with abdominal discomfort 3 months after initial resection of chest wall MCC. Imaging revealed lesions in the pancreas and peripancreatic lymph nodes. Pathology obtained through endoscopic ultrasound confirmed recurrence of MCC. He underwent chemotherapy with cisplatin and etoposide, resulting in a complete resolution of the pancreatic lesions. Unfortunately, he passed away from sudden cardiac arrest while being in remission from MCC. Immunohistochemistry is crucial in differentiating MCC from primary pancreatic glandular and neuroendocrine tumors. While there are no definitive guidelines in the management of pancreatic lesions associated with MCC, checkpoint inhibitor immunotherapy is increasingly being used.

Solid Tumor Metastases to the Pancreas Diagnosed Using Fine-Needle Aspiration

OBJECTIVES

Solid tumor metastases to the pancreas are rare, and only limited literature on the topic is available. In this retrospective study, we reviewed 107 cases of solid tumor metastases to the pancreas diagnosed by fine-needle aspiration (FNA) from 2005 to 2019.

METHODS

Information including the patients' clinical histories, radiologic and pathologic findings, treatments, and follow-up were collected.

RESULTS

The mean age of the patients was 62.4 years. The mean tumor size was 2.64 cm with even distribution throughout the pancreas (head, neck and body, and tail). The most common primary site was the kidney, followed by the lung, skin, and breast and the gynecologic, gastrointestinal, and genitourinary tracts. The most common tumor type was carcinoma, followed by melanoma and sarcoma. In comparison to patients with nonkidney primary cancers, those with primary renal cell carcinoma had a longer median interval between primary diagnosis and metastasis (8.5 vs 4.0 years; P < .01), less often had metastasis outside the pancreas (38% vs 74%; P < .01), and had a significantly longer 5-year survival rate (65.7% vs 24.8%; P < .01).

CONCLUSIONS

FNA plays a crucial role in diagnosing metastases to the pancreas. Metastases originating from kidney and nonkidney primary tumors have distinct clinicopathologic features and prognoses.

Evaluation of metastases to the pancreas with fine needle aspiration: A case series from a single centre with review of the literature

OBJECTIVE

Fine needle aspiration (FNA) is a minimally invasive albeit highly effective modality used to detect solid and cystic pancreatic lesions. This manuscript aims to present our experience in diagnosing metastases to the pancreas and highlight the importance of immunocytochemistry in the diagnostic process. It also aims to provide a brief review of the literature on this topic.

METHODS

We retrospectively searched our archives for cases of metastatic deposits to the pancreas diagnosed with FNA over a 5-year period. We also reviewed the literature for such cases.

RESULTS

We describe seven cases from our archives that metastasised to the pancreas. Three of them (43%) represented metastatic renal cell carcinoma while the rest four comprised deposits from a lung adenocarcinoma, a colon adenocarcinoma, an adrenal leiomyosarcoma, and a small cell carcinoma of the urinary bladder, respectively. History of primary malignancy was available for all seven patients. All diagnoses were confirmed with the use of immunostains. In our literature review, similar to our case series, renal cell carcinoma was the most common metastasis to the pancreas managed with FNA (around one out of three patients; 35%). Of interest, our endoscopic ultrasound-FNA case of pancreatic metastasis from urinary bladder small cell carcinoma is the first reported.

CONCLUSIONS

As metastases to the pancreas are commonly accompanied by diverse prognostic signatures and management strategies compared to primary pancreatic malignancies, their accurate identification is imperative. Pancreatic FNA is a diagnostic modality that can confirm or exclude metastasis to the organ, especially when immunocytochemistry is applied.

Endoscopic ultrasound-guided sampling of solid pancreatic masses: the fine needle aspiration or fine needle biopsy dilemma. Is the best needle yet to come?

Fine needle aspiration (FNA) is currently the standard of care for sampling pancreatic solid masses by using endoscopic ultrasound (EUS). The accuracy of the technique is reported to be high, especially if coupled with the rapid on site evaluation (ROSE), and it has a high safety profile. However, FNA presents some limitations, such as the small amount of tissue that can be collected and the inability of obtaining a core tissue with intact histological architecture, which is relevant to perform immunohistochemical analysis, molecular profiling and, therefore, targeted therapies. Moreover, the presence of the ROSE by an expert cytopathologist is very important to maximize the diagnostic yield of FNA technique; however, it is not widely available, especially in small centers. Hence, the introduction of EUS fine needle biopsy (FNB) with a new generation of needles, which show a high safety profile too and a satisfying diagnostic accuracy even in the absence of ROSE, could be the key to overcome the limitations of FNA. However, FNB has not yet shown diagnostic superiority over FNA. Considering all the technical aspects of FNA and FNB, the different types of needle currently available, comparisons in term of diagnostic yield, and the different techniques of sampling, a tailored approach should be used in order to determine the needle that is most appropriate for the different specific scenarios.

Disseminated metastatic cutaneous melanoma to pancreas and upper gastrointestinal tract diagnosed by endoscopic ultrasound: an unusual case

There is a wide variety of pancreatic neoplasms identified, but the great majority of them are of primary origin. Metastatic disease in the pancreatic parenchyma is quite rare (2-5% of pancreatic malignancies) and most often is quite difficult to differentiate from other primary lesions. Most of the imaging studies fail to give certain discriminating features for metastatic pancreatic neoplasms, contrary to endoscopic ultrasound and tissue sampling, which can provide an accurate diagnosis. In this report, we present a case of a male middle aged man who was admitted to our hospital with painless jaundice and finally was diagnosed with a cutaneous scalp melanoma dispersedly metastasized to the pancreas and upper gastrointestinal tract (stomach and duodenum).

Ancillary Techniques in Cytologic Specimens Obtained from Solid Lesions of the Pancreas: A Review

Advanced methods of molecular characterization have elucidated the genetic, epigenetic, and proteomic alterations associated with the broad spectrum of pancreatic disease, particularly neoplasia. Next-generation sequencing, in particular, has revealed the genomic diversity among pancreatic ductal adenocarcinoma, neuroendocrine and acinar tumors, solid pseudopapillary neoplasm, and other pancreatico-biliary neoplasms. Differentiating these entities from one another by morphologic analysis alone may be challenging, especially when examining the small quantities of diagnostic material inherent to cytologic specimens. In order to enhance the sensitivity and specificity of pancreatic cytomorphology, multiple diagnostic, prognostic, and predictive ancillary tests have been and continue to be developed. Although a great number of such tests have been developed for evaluation of specimens collected from cystic lesions and strictures, ancillary techniques also play a significant role in the evaluation of cytologic specimens obtained from solid lesions of the pancreas. Furthermore, while some tests have been developed to differentiate diagnostic entities from one another, others have been developed to simply identify dysplasia and malignancy. Ancillary studies are particularly important in the subset of cases for which cytomorphologic analysis provides a result that is equivocal or insufficient to guide clinical management. Selection of appropriate ancillary testing modalities requires familiarity with both their methodology and the molecular basis of the pancreatic diseases for which testing is being performed.