Surgery, Gastroenterology and Oncology

Background: Pancreatic cysts are common and difficult to diagnose. CT scan is the best

radiology tool for evaluating pancreatic cysts. The study aimed to differentiate whether

pancreatic injuries are benign or malignant.

Methods: A prospective research with a total of fifty-eight cases from June 2021 to May 2022. Data collected including age, gender, symptoms, and CT scan findings. All cases underwent for CT scan examination.

Results: Most masses were homogeneous in 77.6% in content. About 74.1% of cases have thin walls. Cystic solid components in malignant cyst more than benign cyst. Types of cysts in the benign tumor were detected differently from malignant tumor.

Conclusions: MDCT scan is the easily applicable non-invasive tool of choice for the determination of cystic lesions of the pancreas. Solid components and types of cysts could be positively implicated in CT scan results.

Introduction

Pancreas cysts are commonest and raise challenge delimae of difficulty to the detection, because the quality of radiology techniques improves the detection of asymptomatic pancreatic cysts is increase (1). The commonly detected lesions are serous cystadenomas, pseudocysts, mucinous cystic neoplasms (MCN), intraductal papillary mucinous neoplasms (IPMN), and solid pseudopapillary tumors. Almost all cysts may be pseudocysts, and all cysts are required to be diagnosed to prove whether they are malignant or pre malignant (2). Recently, there have been no gold standard radiological tools for differentia tion (3). CT scan (4), PET scan (5), MR cholangio pancreatography, endoscopic EUSFNA (6), ERCP and tumor markers (2) have been utilized to diagnose cysts which are demonstrated different degrees of sensitive and specific pattern (3).

These lesions are grouped into neoplastic and non neoplastic. Neoplastic tumors can transforming into malignant ones. The pseudocysts, lympho epithelial cyst, and retention cyst are never trans formed into malignant. A percentage of diagnosed cyst has varies, ranging (0.7 36.7%) (7).

Early diagnosis of the cysts raised the dilemma of how to triage and treat cystic lesions (8).

Recently, a CT scan is the best radiology tool for the initial evaluation and follow-up of cyst (9,10). Advantageous properties are the high speed of acquisition with narrow collimations, big images resolution, multi planar imaging, and reformats using volumes

data (11). Additionally, CT is widely available, easily accessible, less costly, highly sensitive, highly accurately, reproducible, and easy to read (11).

The non neoplastic cysts are pseudocysts, retention cysts, cystic pancreatic lymphangioma, dermoid cysts (Epidermoid), and duplication cysts (Ciliated foregut). The neoplastic cysts (PANCREATIC CYSTIC NEOPLASMS) are Mucinous cystic lesions (Intra ductal papillary muci nous neoplasm (IPMNs), Mucinous cystic neoplasm (MCNs)), and Nonmucinous Cystic Neoplastic Lesions, Serous cystic neoplasm (SCNs), Solid pseudopapillary neoplasm (SPNs), cystic pancreatic neuroendocrine tumor, and Cystic acinar cell neoplasm. Others are Pancreatic ductal adenocarcinoma with cystic degener ation, and Intra ductal tubule papillary neoplasm (ITPN) (12).

Aims of the study to differentiate whether pancreatic lesions are malignant or non malignant.

Methods

Study Design and Setting

A prospective work with a total of fifty-eight patients with dorsal abdominal pain radiating to the anterior were enrolled in the study during the period from 12th June 2021 to 20th May 2022. The sample consisted of 19 (32.8%) male and 39(67.2%) female, their median age, of 42 years (mean= 41.59±11.9 years).

Data Collection

Participants' data including age, sex, and symptoms, and CT scan findings include: lesion sites, parenchymal atrophy, number of cystic lesions, diameter of largest cyst, calcification, ductal dilation, solid components, cyst contour, enhancement, cyst types, thick wall, lymphovascular invasion and communication cyst-duct.

Exclusion Criteria

1. Pregnant women

2. Allergy to contrast.

3. Unwilling.

4. Renal disorder.

Protocols

CT scan was performed utilizing the Siemens system (SOMATOM Definition AS VA44A; Siemens, Somaris/7 syngo CT 67002 2012B, Germany) and 64 slice multi detector) CT system (Philips).

Ethical Approval

The study was approved by The Medical Ethical Committee of the College of Medicine, Babylon University.

Statistical Analysis

A SPSS version 24.0, Chicago: SPSS, Inc. was used. Findings were described into frequencies and percents for nominal and (mean, and SD) calculations for ordinal. Pearson’s test was used. A one sided P <0.05 was considered statistically significant.

Results

CT scan findings in non malignant and malignant cysts are listed in table 1. All pancreatic cysts features were insignificant between benign and malignant tumors. Additionally, solid components of cysts showed a statistically significant difference in malignant pancreatic cysts more than benign cysts (P= 0.004). Furthermore, types of cysts in benign pancreatic tumors were investigated significantly differently from malignant tumors (P= 0.016) (table 1).

Table 1 - CT scan findings in benign and malignant lesions.

Discussion

In correlation between benign and malignant in this study, the data showed that most pancreatic cyst features were differed insignificantly (P > 0.05). Additionally, solid components of cysts showed a statistically significant difference in malignant lesions more than benign lesions (P = 0.004). Furthermore, types in benign pancreatic tumors were detected significantly differently from malignant tumors (P = 0.016). Crippa et al. reported that MCNs documented 25% of all cystic malignancies and IPMNs were 50% (13). Another studies of 851 patients showed that IPMNs assumed for 38% of cysts, MCNs for 23%, SCNs for 16%, and solid pseudopapillary tumors for 3% (14). This misguidance can be diminished with a multi disciplinary team approach to study these cysts with the incorpora tion of the clinical, radiologic, and pathologic findings before reaching a definite diagnosis (15).

Multi detector CT (MDCT) improves spatial and temporal resolution and significant impact on the ability to assess a cyst's variety of pancreas with raised accuracy and sophistication (16). Cystic pancreatic tumors do have radiology findings that may permit them to provide a specific and accurate diagnosis or, to narrow the differential diagnosis. Moreover, CT scans now serve as the primary tool to risk stratify cysts and determine which lesions can be safely treated conservatively plus follow up (17). The prevalence ranged from 1.2% (18) to 2.6 % (19).

Recently in modern CT scans, images are taken with an extremely thin collimation plus a slice thickness of only 0.625 to 0.75 mm, then reconstructed into 3 to 5 mm axial sections (16, 20). 3 D reconstruction recently has now proven technique for the diagnosis of cyst lesions with two most commonly utilized include: (1) maximum intensity projection (MIP) imaging and (2) volume rendering (VR).

Raman and Fishman found this technique to be very helpful for cysts determination, assessment of the internal architecture of cysts, and demonstrating the association of a cyst to the neighboring duct (16).

Several researches in the past have shown MDCT to be very accurate in the characterization of cysts, with accuracy was 56% to 85%, with accuracies as high as 79% for distinguishing benign from malignant cysts and as high as 85% for distinguishing mucinous type and non mucinous types (21,22).

Optimal photos of cysts require helical (spiral) CT or multi detector CT (MDCT), in addition to rapid adminis tration of IV contrast. The helical scanning, axial images 5 mm collimation, 7 mm collimation, pitch 1.5 over the upper abdomen, and pitch 2 for the rest of the abdomen can be obtained. Acquisition starts from the top of the diaphragm at approximately 60 sec. The MDCT scanner acquired a two phase acquisition technique that can be employed (20) which are arterial dominant phase, portal dominant phase, and

dual phase pancreatic imaging.

Conclusions

MDCT scan is the easily non invasive applicable tool for the evaluation of pancreatic cysts. Detection of site and number of cyst, dilation of duct, solid components, and types are helpful in differentiating among malignant and benign lesions. Solid components of cyst and types of cyst could be positively implicated malignant lesions.

Conflicts of Interest

The authors declare no conflict of interest regarding this article.

Funding

None.

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