Natural History and Management of Intraductal Papillary Mucinous Neoplasms: Current Evidence

Utilization of texture features of volumetric ADC maps in differentiating between serous cystadenoma and intraductal papillary neoplasms

INTRODUCTION

The rising incidence of incidental detection of pancreatic cystic neoplasms has compelled radiologists to determine new diagnostic methods for the differentiation of various kinds of lesions. We aim to demonstrate the utility of texture features extracted from ADC maps in differentiating intraductal papillary mucinous neoplasms (IPMN) from serous cystadenomas (SCA).

METHODS

This retrospective study was performed on 136 patients (IPMN = 87, SCA = 49) split into testing and training datasets. A total of 851 radiomics features were extracted from volumetric contours drawn by an expert radiologist on ADC maps of the lesions. LASSO regression analysis was used to determine the most predictive set of features and a radiomics score was developed based on their respective coefficients. A hyper-optimized support vector machine was then utilized to classify the lesions based on their radiomics score.

RESULTS

A total of four Wavelet features (LHL/GLCM/LCM2, HLL/GLCM/LCM2, /LLL/First Order/90percent, /LLL/GLCM/MCC) were selected from all of the features to be included in our classifier. The classifier was optimized by altering hyperparameters and the trained model was applied to the validation dataset. The model achieved a sensitivity of 92.8, specificity of 90%, and an AUC of 0.97 in the training data set, and a sensitivity of 83.3%, specificity of 66.7%, and AUC of 0.90 in the testing dataset.

CONCLUSION

A support vector machine model trained and validated on volumetric texture features extracted from ADC maps showed the possible beneficence of these features in differentiating IPMNs from SCAs. These results are in line with previous regarding the role of ADC maps in classifying cystic lesions and offers new evidence regarding the role of texture features in differentiation of potentially neoplastic and benign lesions.

Pancreatic Intraductal Papillary Mucinous Neoplasms: A Narrative Review

INTRODUCTION

Intraductal papillary mucinous neoplasms (IPMNs) are the most frequent cystic pancreatic neoplasm. They derive from the main pancreatic duct or branch ducts.

AIM

This narrative review aims to present and compare the current guidelines on the management of IPMNs.

MATERIALS AND METHODS

We reviewed the most important scientific literature on the management of IPMNs.

DISCUSSION

The clinical presentation of IPMNs is usually nonspecific; common symptoms are abdominal pain, weight loss, and jaundice. There are no sex differences, and the incidence increases with age. It is considered a premalignant lesion associated with synchronous or metachronous carcinomas. Multifocal sites within the pancreas and the presence of solid components, like mural nodules, are predictive factors for developing malignancy. Magnetic resonance imaging (MRI) is the imaging technique of choice. However, computed tomography (CT) and endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) can also contribute to the diagnosis. Resection is the optimal treatment for IPMNs that arise from the main duct, while several indications are suggested for the surgery on IPMNs of branch ducts.

CONCLUSION

The decision on surgery is not always a simple task and should be based on high-risk features of the neoplasm. In any case, re-examination and follow-up are highly recommended.

[The mistakes in diagnosis of pancreatic intraductal papillary mucinous tumor]

It is presented surgical treatment of the patient with pancreatic intraductal papillary mucinous tumor who was under observation with diagnosis of chronic pancreatitis for a long time. Recurrent tumor with possible malignant transformation to carcinoma was suspected in 5 years after pancreaticoduodenectomy. It was supposed to perform pancreatic stump extirpation. Redo surgery did not reveal any tumor. The cause of recurrent pain was pancreatic duct obliteration at the level of anastomosis.

Intraductal tubular papillary neoplasm (ITPN), a novel entity of pancreatic epithelial neoplasms and precursor of cancer: A case report and review of the literature

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Intraductal tubular papillary neoplasm (ITPN) displays a very rare subtype of epithelial neoplasms of the pancreas.

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To date, little is known about ITPN and particularly about pancreatic cancer arising in this tumor entity.

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ITPN reveals a potential of malignant transformation. Radical surgical resection and oncologic follow-up is warranted.

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When compared to ductal adenocarcinoma, patients with ITPN reveal less lymph node metastasis and a better overall survival.

Background

Intraductal tubular papillary neoplasm (ITPN) displays a very rare subtype of epithelial neoplasms of the pancreas. ITPN is characterized by intraductal tubulopapillary growth and cellular dysplasia. In contrast to intraductal papillary neoplasm (IPMN) no overt epithelial mucin production is observed. To date, little is known about ITPN and particularly about pancreatic cancer arising in this tumor entity.

Case presentation

A 68-year-old male presented at our hospital with a distal bile duct occlusion suspicious for adenocarcinoma of the pancreatic head. Preoperative staging revealed no signs of distant metastasis. The patient was surgically explored and pylorus preserving duodenopancreatectomy was performed for a solid pancreatic head tumor. Final histopathology surprisingly revealed an ITPN with an associated invasive carcinoma pT3, pN0 (0/12), R0, G2.

Discussion

Patients with ITPN frequently present with jaundice suspicious for a bile duct stenosis or a malignant tumor of the pancreatic head. Although, it is possible to diagnose ITPN by endoscopic retrograde cholangiopancreaticography, many tumors are found not before histopathological examination. Differential diagnosis includes ductal adenocarcinoma of the pancreas, neuroendocrine tumors, IPMN, distal bile duct tumors, and solid pseudopapillary neoplasms. Using immunohistochemistry, other entities of pancreatic tumors can be ruled out. In case of R0 resection oncological prognosis is described to be more favorable when compared to regular ductal adenocarcinoma.

Conclusion

ITPN displays a rare entity of pancreatic neoplasms. As shown in the present case report, there is a relevant potential of malignant transformation and therefore radical surgical resection and oncologic follow-up is warranted.