Introduction

Please find here a collection publicly available resources related to pancreatic resection for observed mucinous cystic neoplasms. This collection features titles, summaries, quotations, and link backs to the source articles.  I included some quotations from the source articles, so you don’t have to read the full article unless you want to.  Please check back for updates to the article.  Through the presentation of this information I intend to support the following hypotheses:

  • Current diagnostic methods to identify cystic histology remain woefully inadequate at the same time modern radiology lead to higher incidence of cystic legions.

Basic Run Down of Pancreatic Cysts

http://www.pancyst.org/faqs.aspx

Do all pancreatic cysts need to be surgically removed?
No. Pancreatic cysts have variable malignant potential. Mucinous pancreatic cysts are the most common pancreatic cysts and have significant potential to progress to pancreatic cancer. Despite this, most mucinous pancreatic cysts without worrisome features may be safely but carefully watched.

Identifying patients with pancreatic cysts who do not require resection

This comprehensive report addresses critical concerns about advances in radiology that permit an alternative treatment to the controversial mandatory resection some doctors promote.  The data provides accurate statistics to help clarify patient outlook.  The rhetoric highlights the uncertain nature of pancreatic cystic malignancy and offers an alternative to resection.  This article contains charts and illustrations for a subset of 539 patients from 1995 to 2005 with pancreatic cysts.

The appropriate management of patients with cystic lesions of the pancreas is controversial.
…also…
Several recent reports, including a previous study from the authors’ institution, have recommended a more selective approach to resection. This approach argues that improved radiographic imaging techniques and an improved understanding of the various histologic entities allow the identification of a group of patients with an extremely low risk of malignancy. Most studies reporting selective management have recommended nonoperative management (radiographic follow-up) for patients with small, incidentally discovered cysts of the pancreas. This approach avoids the risks of operation in patients with benign lesions, but with current limitations in nonresectional diagnosis, cannot guarantee that a malignancy is not mistakenly being observed.

Cyst fluid amylase and CEA levels in the differential diagnosis of pancreatic cysts

https://www.ncbi.nlm.nih.gov/pubmed/24965184

The overall accuracies of cyst fluid amylase and CEA were 69 and 85%, respectively.

CONCLUSIONS:

Cyst fluid amylase analysis does not differentiate between MCN and IPMN. The combination of cyst fluid CEA and amylase value may increase the diagnostic accuracy for differentiating mucinous neoplasms from pseudocysts.

Pancreatic Cyst Fluid Analysis

http://www.jgld.ro/2011/2/13.pdf

Efforts to differentiate among these tumors from imaging tests have met with mixed success, with up to 40% of neoplastic cysts misdiagnosed as pseudocyts [7, 8]. Moreover, the reported overall accuracy has been highly variable from 20% to 80% [9, 10].

 

The sensitivity, specificity and PPV of molecular diagnosis were 83%,100% and 100% for a malignant cyst and 86%, 93% and 95% for a benign mucinous cyst. The conclusion reached was that molecular analysis adds diagnostic value to preoperative diagnostics. Last, but not least, the cost effectiveness of different strategies of management was studied in asymptomatic pancreatic cystic neoplasms [48]. The study has further emphasized the utility of EUS-guided FNA with cyst fluid analysis. The authors compared three approaches in solitary asymptomatic pancreatic cystic neoplasms.

The approaches were:
1) no specific intervention;
2) an aggressive surgical intervention;
3) EUS-guided FNA with cyst fluid analysis for risk stratification, with patients with mucinous cysts considered for resection.

The results showed that the latter approach yielded the highest quality adjusted life years with an acceptable incremental cost effectiveness ratio. Conclusion There is a need for a panel of molecular markers that can help in unraveling the diagnostic conundrum of pancreatic cystic lesions. A cost-effective diagnostic algorithm which would have high accuracy would be very helpful in the work up of pancreatic cystic lesions and could improve prognosis considerably. The use of tumor and molecular markers in conjunction with multimodality detection such as CT, MR and EUS-FNA permits risk stratification and is cost-effective. Further studies require to be conducted to validate the effectiveness of tumor and molecular markers as shown in prior studies

Conclusion: There is a need for a panel of molecular markers that can help in unraveling the diagnostic conundrum of pancreatic cystic lesions. A cost-effective diagnostic algorithm which would have high accuracy would be very helpful in the work up of pancreatic cystic lesions and could improve prognosis considerably. The use of tumor and molecular markers in conjunction with multimodality detection such as CT, MR and EUS-FNA permits risk stratification and is cost-effective. Further studies require to be conducted to validate the effectiveness of tumor and molecular markers as shown in prior studies

The incidental cystic pancreas mass: a practical approach

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3460559/

These lesions have created a diagnostic and management dilemma for both clinicians and radiologists: should these lesions be ignored, watched, aspirated, or removed?

Asymptomatic cystic lesions that are <3 cm in size, without mural thickening, mural nodularity, solid components, or dilation of the main pancreatic duct are usually benign and can be safely watched.

Imaging of benign and malignant cystic pancreatic lesions and a strategy for follow-up

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2999337/

If suspicious features are present, a more aggressive approach, including cyst aspiration, biopsy of solid components and potential surgical resection need to be considered.

Pancreatic cystic neoplasms: Review of current knowledge, diagnostic challenges, and management options

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4374202/

EUS findings associated with malignant MCN include size >4 cm, cyst wall irregularity and thickening, septal thickening, intracystic solid regions, presence of wall calcification, PD dilation, presence of collateral vessels, and the presence of a frank mass or mural nodules.

Role of EUS-FNA Based Cytology in Diagnosis of Mucinous Pancreatic Cystic Lesions: A Systematic Review and Meta-analysis

Summary: Can’t exactly get past the jargon, but I suspect this says EUS-FNA Cytology scores about 95% correct identifying MCNs.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4169146/

EUS-FNA based cytology has overall low sensitivity but good specificity in differentiating MCLs from NMCLs. Further research is required to improve the overall sensitivity of EUS-FNA based cytology to diagnose MCLs while evaluating PCL.

Cyst Fluid Analysis in the Differential Diagnosis of Pancreatic Cysts

A Comparison of Pseudocysts, Serous Cystadenomas, Mucinous Cystic Neoplasms, and Mucinous Cystadenocarcinoma

Some data for cyst classification purposes.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1242732/pdf/annsurg00071-0061.pdf

Imaging of benign and malignant cystic pancreatic lesions and a strategy for follow up

Summary: This article contains a concise appraisal of the MCN condition.

http://www.wjgnet.com/1949-8470/full/v2/i9/345.htm

Mucinous cystic neoplasms (MCNs) are usually solitary, range from 6-35 cm in size, are generally found in the body and tail of the pancreas and account for 10% of cystic neoplasms seen in the pancreas[12]. These tumors typically have a thick wall and are multilocular[3]. They do not communicate with the main pancreatic duct except through fistulae[3,13]. MCNs have < 6 locules which are usually > 2 cm in size. The internal contents of the cyst may be hemorrhagic, necrotic or consist of mucinous material. MCNs typically have internal nodules, which histological may harbor high-grade dysplasia or invasive carcinoma[13]. MCNs of the pancreas resemble MCNs of the ovary and are seen in women of reproductive age (> 95%) (mean age, 45 years)[1316]. The cyst wall has two layers. The inner layer of cells secretes mucin and the outer layer of cells resembles ovarian stroma. Calcifications may be noted in the periphery of the tumor or in the capsule in 10%-25% of cases[7]. These patients may present with vague abdominal pain, weight loss and anorexia.

MCNs can appear on imaging as a single large cyst with multiple locules, a thick outer wall, septations, and enhancing intramural nodules. Sometimes calcifications can be present on the outer wall[3], and the wall may enhance on the delayed phase. On MRI, the fluid within the cyst may have a low signal on T1-weighted images (T1WI) and a high signal on T2WI, however, increased signal on T1WI has also been observed[17]. It is not possible on imaging to exclude malignancy but the presence of enhancing nodules increases the likelihood[16].

Diagnosis and management of cystic lesions of the pancreas

Summary: In-depth information for all pancreatic cystic lesions.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4502158/

It may be difficult to distinguish between pseudocysts and pancreatic mucinous cysts without the use of cyst fluid analysis in some cases.