Clinical diagnosis and management of pancreatic mucinous cystadenoma and cystadenocarcinoma: Single-center experience with 82 patients

Implications of pregnancy on MCN of the pancreas: A multicentric case-control study

BACKGROUND

Mucinous cystic neoplasms (MCN) of the pancreas express estrogen and progesterone receptors. Several case reports describe MCN increasing in size during gestation. The aim of this study is to assess if pregnancy is a risk factor for malignant degeneration of MCN.

METHODS

All female patients who underwent pancreatic resection of a MCN between 2011 and 2021 were included. MCN resected or diagnosed within 12 months of gestation were defined perigestational. MCN with high grade dysplasia or an invasive component were classified in the high grade (HG) group. The primary outcome was defined as the correlation between exposure to gestation and peri-gestational MCN to development of HG-MCN.

RESULTS

The study includes 176 patients, 25 (14 %) forming the HG group, and 151 (86 %) forming the low grade (LG) group. LG and HG groups had a similar distribution of systemic contraceptives use (26 % vs. 16 %, p = 0.262), and perigestational MCN (7 % vs 16 %, p = 0.108). At univariate analysis cyst size ≥10 cm (OR 5.3, p < 0.001) was associated to HG degeneration. Peri gestational MCN positively correlated with cyst size (R = 0.18, p = 0.020). In the subgroup of 14 perigestational MCN patients 29 % had HG-MCN and 71 % experienced cyst growth during gestation with an average growth of 55.1 ± 18 mm.

CONCLUSIONS

Perigestational MCN are associated to increased cyst diameter, and in the subset of patients affected by MCN during gestation a high rate of growth was observed. Patients with a MCN and pregnancy desire should undergo multidisciplinary counselling.

A narrative review on rare types of pancreatic cancer: should they be treated as pancreatic ductal adenocarcinomas?

Pancreatic cancer is one of the deadliest malignancies in humans and it is expected to play a bigger part in cancer burden in the years to come. Pancreatic ductal adenocarcinoma (PDAC) represents 85% of all primary pancreatic malignancies. Recently, much attention has been given to PDAC, with significant advances in the understanding of the mechanisms underpinning disease initiation and progression, along with noticeable improvements in overall survival in both localized and metastatic settings. However, given their rarity, rare histological subtypes of pancreatic cancer have been underappreciated and are frequently treated as PDAC, even though they might present non-overlapping molecular alterations and clinical behavior. While some of these rare histological subtypes are true variants of PDAC that should be treated likewise, others represent separate clinicopathological entities, warranting a different therapeutic approach. In this review, we highlight clinical, pathological, and molecular aspects of rare histological types of pancreatic cancer, along with the currently available data to guide treatment decisions.

Rare tumours of the pancreas: monocentric study

PURPOSE

The biology of rare pancreatic tumours, which differs from that of ductal pancreatic cancer, requires increased attention. Although the majority of rare pancreatic tumours are benign, it is difficult to decide whether an invasive component exists without complete removal of the lesion, despite considerable progress in diagnosis. We are investigating a large cohort of patients with histologically confirmed epithelial non-ductal non-neuroendocrine neoplasms of the pancreas.

METHODS

Here we analyze long-term survival from patients, who underwent resection of histologically confirmed epithelial non-ductal non-neuroendocrine neoplasms of the pancreas. At our department between Jan 1st, 1999, and Dec 31st, 2019. The median follow-up was 61 (range 0-168) month. All statistical analyses were performed using SPSS 26.0 (IBM, Chicago, IL, USA) software.

RESULTS

46 patients (48%) were followed up for more than 5 years, 18 patients (19%) for more than 10 years. The 5-year and 10-year survival rates for rare non-invasive pancreatic tumours were 72% and 55% respectively. The proportion of rare tumour entities (non-ductal and non-neuroendocrine) increased continuously and statistically significantly (p = 0.004) from 4.2 to 12.3% in our clinic between 1999 and 2019. If there is no invasive growth yet, there is a varying risk of malignant degeneration in the course of the disease. Therefore, the indication for pancreatic resection is still the subject of discussion.

CONCLUSION

The long-term prognosis of rare epithelial pancreatic tumours after R0 resection-even if they are already malignant-is much better than that of ductal pancreatic cancer.

A preliminary study on the establishment of a cyst and cystic neoplasm tissue-mimicking model

Context

The present experimental models of cystic diseases are not adequate and require further investigation.

Aim

In this study, a new way of producing a tissue-mimicking model of cysts and cystic neoplasms was evaluated.

Settings and Design

To simulate cysts and cystic neoplasms, ex vivo rabbit normal bladders and VX2-implanted tumor bladders were produced, fixed, and embedded in agarose gel.

Methods and Materials

The samples were classified into four groups based on tumor features and the maximal transverse diameter of the rabbit bladder, which were assessed using computer tomography (CT) imaging and statistically analyzed.

Statistical Analysis Used

Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) software. The t-test was used for analyzing enumeration data.

Results

Twenty-one rabbit bladders (21/24) were successfully removed and prepped for this experiment, comprising eleven normal bladders (11/24) and ten implanted with VX2 tumors (10/24). The gelling ingredient used to form the visualization and fixation matrix was agarose at a concentration of 4 g/200 mL. The temperature of the agarose solution was kept constant at 40-45°C, which is the optimal temperature range for ex vivo normal bladder and implanted VX2 tumor bladder insertion. The average time required to embed and fix the bladders in agarose gel was 45.0 ± 5.2 minutes per instance. The gel-fixing matrix's strength and light transmittance were enough for building the models.

Conclusion

We created an experimental tissue-mimicking model of cysts and cystic neoplasms with stable physicochemical features, a safe manufacturing method, and high repeatability. These models may be used to assist with cystic lesion diagnosis and treatment techniques.

It is not necessary to resect all mucinous cystic neoplasms of the pancreas: current guidelines do not reflect the actual risk of malignancy

BACKGROUND

Mucinous Cystic Neoplasms (MCN) of the pancreas are premalignant cysts for which current guidelines support pancreatic resection. The primary aim of this systematic review and meta-analysis is to define the pooled rate of malignancy for MCN.

METHODS

A systematic review of eligible studies published between 2000 and 2021 was performed on PubMed and Embase. Primary outcome was rate of malignancy. Data regarding high-risk features, including cyst size and mural nodules, were collected and analyzed.

RESULTS

A total of 40 studies and 3292 patients with resected MCN were included in the final analysis. The pooled rate of malignancy was 16.1% (95%CI 13.1-19.0). The rate of malignant MCN in studies published before 2012 was significantly higher than that of studies published after recent guidelines were published (21.0% vs 14.9%, p < 0.001). Malignant MCN were larger than benign (mean difference 25.9 mm 95%CI 14.50-37.43, p < 0.001) with a direct correlation between size and presence of malignant MCN (R2 = 0.28, p = 0.020). A SROC identified a threshold of 65 mm to be associated with the diagnosis of malignant MCN. Presence of mural nodules was associated with the diagnosis of a malignant MCN (OR = 4.34, 95%CI 3.00-6.29, p < 0.001).

CONCLUSION

Whereas guidelines recommend resection of all MCN, the rate of malignancy in resected MCN is 16%, implying that surveillance has a role in most cases, and that surgical selection criteria are warranted. Size and presence of mural nodules are significantly associated with an increased risk of malignant degeneration, small MCN and without mural nodules can be considered for surveillance.

Pancreatic Cystic Neoplasms and Pregnancy: A Systematic Review of Surgical Cases and a Case Report of a Fully Laparoscopic Distal Pancreatectomy

BACKGROUND

Mucinous cystic neoplasms and solid pseudopapillary neoplasms are the most common pancreatic tumors occurring in women of fertile age and in pregnant women. The aim of this study is to provide an updated literature review on this association and to present a fully laparoscopic resection of a pregnancy-associated pancreatic cystic neoplasm.

MATERIALS AND METHODS

A systematic literature review was performed using PubMed (MEDLINE), Scopus, Ovid, ISI Web of Science, and Google Scholar for searching. The syntax was (pancr*) AND (cyst*) AND (pregn*) AND (tumor). Only English-language articles describing pancreatic surgical resections were included.

RESULTS

Forty-seven case reports were included. The mean age of the patients was 29.6±5.3. Nine patients (20%) required emergency surgery, 4 (9%) due to cyst rupture, and 5 (11%) due to hemorrhage. Four patients (9%) suffered a miscarriage, and 2 (5%) opted for pregnancy termination; the rest of the women delivered a healthy newborn (86%, n=36). Thirty percent (n=14) of the resected neoplasms were malignant, and among mucinous cystic lesions, this raised to 45% (n=11). All patients diagnosed during the third trimester were resected postpartum, whereas 26/34 (76%) of patients diagnosed during the first 2 trimesters underwent surgery before delivery.

CONCLUSIONS

The most worrisome complications in pregnancy-associated pancreatic cysts are bleeding or rupture. Mucinous cystic neoplasm has a tendency to grow during pregnancy. A postpartum resection was generally preferred when the cystic neoplasm was diagnosed during the third trimester. This report is the first to describe a fully laparoscopic pancreatic resection.

Application of CT-Based Radiomics in Discriminating Pancreatic Cystadenomas From Pancreatic Neuroendocrine Tumors Using Machine Learning Methods

Objectives

The purpose of this study aimed at investigating the reliability of radiomics features extracted from contrast-enhanced CT in differentiating pancreatic cystadenomas from pancreatic neuroendocrine tumors (PNETs) using machine-learning methods.

Methods

In this study, a total number of 120 patients, including 66 pancreatic cystadenomas patients and 54 PNETs patients were enrolled. Forty-eight radiomic features were extracted from contrast-enhanced CT images using LIFEx software. Five feature selection methods were adopted to determine the appropriate features for classifiers. Then, nine machine learning classifiers were employed to build predictive models. The performance of the forty-five models was evaluated with area under the curve (AUC), accuracy, sensitivity, specificity, and F1 score in the testing group.

Results

The predictive models exhibited reliable ability of differentiating pancreatic cystadenomas from PNETs when combined with suitable selection methods. A combination of DC as the selection method and RF as the classifier, as well as Xgboost+RF, demonstrated the best discriminative ability, with the highest AUC of 0.997 in the testing group.

Conclusions

Radiomics-based machine learning methods might be a noninvasive tool to assist in differentiating pancreatic cystadenomas and PNETs.

Validation of serum tumor biomarkers in predicting advanced cystic mucinous neoplasm of the pancreas

BACKGROUND

Early detection of advanced cystic mucinous neoplasms [(A-cMNs), defined as high-grade dysplasia or malignancy] of the pancreas is of great significance. As a simple and feasible detection method, serum tumor markers (STMs) may be used to predict advanced intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs). However, there are few studies on the usefulness of STMs other than carbohydrate antigen (CA) 19-9 for early detection of A-cMNs.

AIM

To study the ability of five STMs-CA19-9, carcinoembryonic antigen (CEA), CA125, CA724, and CA242 to predict A-cMNs and distinguish IPMNs and MCNs.

METHODS

We mainly measured the levels of each STM in patients pathologically diagnosed with cMNs. The mean levels of STMs and the number of A-cMN subjects with a higher STM level than the cutoff were compared respectively to identify the ability of STMs to predict A-cMNs and distinguish MCNs from IPMNs. A receiver operating characteristic curve with the area under curve (AUC) was also created to identify the performance of the five STMs.

RESULTS

A total of 187 patients with cMNs were identified and 72 of them showed A-cMNs. We found that CA19-9 exhibited the highest sensitivity (SE) (54.2%) and accuracy (76.5%) and a moderate ability (AUC = 0.766) to predict A-cMNs. In predicting high-grade dysplasia IPMNs, the SE of CA19-9 decreased to 38.5%. The ability of CEA, CA125, and CA724 to predict A-cMNs was low (AUC = 0.651, 0.583, and 0.618, respectively). The predictive ability of CA242 was not identified. The combination of STMs improved the SE to 62.5%. CA125 may be specific to the diagnosis of advanced MCNs.

CONCLUSION

CA19-9 has a moderate ability, and CEA, CA125, and CA724 have a low ability to predict A-cMNs. The combination of STM testing could improve SE in predicting A-cMNs.

Clinical implication of serum CA125 for the prediction of malignancy in mucinous cystic neoplasms of the pancreas

Mucinous cystic neoplasms (MCNs) of the pancreas have malignant potential. Carbohydrate antigen 125 (CA125) is a common widely used biomarker for cancers. However, the role of CA125 in predicting the malignant change of MCNs is currently unidentified. Patients with resected and pathologically confirmed MCN were identified from a prospectively maintained database. The predictive role of serum CA125 in assessing malignant change of MCNs was analyzed and compared with serum carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA). This study included 164 patients with MCN (low/moderate grade, 153 cases; high grade and invasive, 11 cases). The serum levels of CA125 in the high grade and invasive group (45.1±42.1 U/ml) was significantly higher than those in the low/moderate grade group (21.0±46.2 U/ml, P=0.006). The area under the receiver operating characteristic (ROC) curve of CA125 (0.75) for predicting malignancy of MCNs was higher than that of CA19-9 (0.68) or CEA (0.72). The prediction value of CA125 was improved when combined with CEA (CA125 alone, sensitivity 36.4%, specificity 90.6%, accuracy 86.6%; combined with CEA, sensitivity 45.5%, specificity 88.2%, accuracy 85.0%). It was concluded that serum CA125 shows value in predicting the malignant change of MCNs, especially when combined with serum CEA.