Salivary duct carcinoma (SDC) is a major malignant salivary gland tumor that usually forms a solid tumor. Non-necrotic macrocystic SDCs have rarely been reported among salivary gland tumors. A 78-year-old Japanese man with a submandibular gland tumor was evaluated radiologically, pathologically, and immunohistochemically. A multilocular lesion with a maximum size of 6 cm was radiologically observed in the left submandibular region. It had been noticed 20 years earlier. Malignant cytological result was obtained, and surgical resection was performed. Pathological examination revealed a non-necrotic, macrocystic submandibular gland tumor lined with glandular, cribriform, or papillary forms of atypical cuboidal cells. Frankly invasive components were observed in intercystic areas. Intraductal, mucoepidermoid, and secretory carcinomas were identified as pathological differential diagnoses because of their macrocystic morphology. We diagnosed SDC because there was no intraductal growth based on the lack of myoepithelial markers, diffuse immunoreactivity to gross cystic disease fluid protein15, androgen receptor, and mammaglobin and immunonegativity to S100 and p63. Postoperative positron emission tomography revealed the absence of lymph node and distant metastases. The patient was disease-free 9 months after surgery. Salivary duct carcinoma can be included in the differential diagnoses of cystic salivary gland tumors.

BACKGROUND: Pancreatoduodenectomy (PD) has a considerable surgical risk for complications and late metabolic morbidity. Parenchyma-sparing resection of benign tumors has the potential to cure patients associated with reduced procedure-related short- and long-term complications.
METHODS: Pubmed, Embase, and Cochrane libraries were searched for studies reporting surgery-related complications following PD and duodenum-preserving total (DPPHRt) or partial (DPPHRp) pancreatic head resection for benign tumors. A total of 38 cohort studies that included data from 1262 patients were analyzed. In total, 729 patients underwent DPPHR and 533 PD.
RESULTS: Concordance between preoperative diagnosis of benign tumors and final histopathology was 90.57% for DPPHR. Cystic and neuroendocrine neoplasms (PNETs) and periampullary tumors (PATs) were observed in 497, 89, and 31 patients, respectively. In total, 34 of 161 (21.1%) patients with intraepithelial papillar mucinous neoplasm exhibited severe dysplasia in the final histopathology. The meta-analysis, when comparing DPPHRt and PD, revealed in-hospital mortality of 1/362 (0.26%) and 8/547 (1.46%) patients, respectively [OR 0.48 (95% CI 0.15-1.58); p = 0.21], and frequency of reoperation of 3.26 % and 6.75%, respectively [OR 0.52 (95% CI 0.28-0.96); p = 0.04]. After a follow-up of 45.8 ± 26.6 months, 14/340 patients with intraductal papillary mucinous neoplasms/mucinous cystic neoplasms (IPMN/MCN, 4.11%) and 2/89 patients with PNET (2.24%) exhibited tumor recurrence. Local recurrence at the resection margin and reoccurrence of tumor growth in the remnant pancreas was comparable after DPPHR or PD [OR 0.94 (95% CI 0.178-5.34); p = 0.96].
CONCLUSIONS: DPPHR for benign, premalignant neoplasms provides a cure for patients with low risk of tumor recurrence and significantly fewer early surgery-related complications compared with PD. DPPHR has the potential to replace PD for benign, premalignant cystic and neuroendocrine neoplasms.

Currently, the most frequently used surgical treatment for symptomatic, benign, premalignant cystic and neuroendocrine neoplasms of the pancreatic head is the Whipple procedure or pylorus-preserving pancreatoduodenectomy (PD). However, when performed for treatment of benign tumors, PD is a multiorgan resection involving loss of pancreatic and extrapancreatic tissue and functions. PD for benign neoplasm is associated with the risk of considerable early postoperative complications and an in-hospital mortality of up to 5%. Following the Whipple procedure a new onset of diabetes mellitus is observed in 14-20% and new exocrine insufficiency in 25-45%, leading to metabolic dysfunction and impairment of quality of life persisting after resection of benign tumors. Symptomatic neoplasms are indication for surgery. Patients with asymptomatic pancreatic tumors are treated according to the criteria of surveillance protocols. The goal of surgical treatment for asymptomatic patients is, according to the guideline criteria, interruption of the surveillance program before the development of an advanced stage cancer associated with the neoplasm. Tumor enucleation and duodenum-preserving pancreatic head resection, either total or partial, are parenchyma-sparing resections for benign neoplasms of the pancreatic head. The first choice for small tumors is enucleation; however, enucleation is associated with an increased risk of pancreatic fistula B + C following pancreatic main duct injury. Duodenum-preserving total or partial pancreatic head resection has the advantage of low postoperative surgery-related complications, a mortality of < 0.5% and maintenance of the endocrine and exocrine pancreatic functions. Parenchyma-sparing pancreatic head resections should replace classical Whipple procedures for neoplasms of the pancreatic head.
UNASSIGNED: Das gegenwärtig am häufigsten angewendete operative Verfahren bei symptomatischen, benignen, prämalignen zystischen und neuroendokrinen Tumoren des Pankreaskopfs ist die Whipple-Operation oder pyloruserhaltende Pankreatoduodenektomie (PD); die PD ist jedoch eine Multiorganresektion, bei der pankreatisches und extrapankreatisches Gewebe sowie dessen Funktionen verloren gehen. Die PD ist auch bei benignen Neoplasien mit dem Risiko erheblicher Komplikationen in der frühen postoperativen Phase assoziiert und geht mit einer Krankenhausmortalität von bis zu 5 % einher. Nach Whipple-Operation wird bei 14–20 % der Patienten ein sich neu manifestierender Diabetes mellitus beobachtet, bei 25–45 % tritt eine exokrine Insuffizienz auf, was zu einer nach Resektion benigner Tumoren persistierenden metabolischen Dysfunktion und Beeinträchtigung der Lebensqualität führt. Symptomatische Neoplasien sind Indikation für die operative Therapie. Patienten mit asymptomatischen Pankreastumoren werden gemäß den Kriterien von Surveillance-Protokollen behandelt. Ziel der operativen Therapie bei asymptomatischen Patienten ist entsprechend den Leitlinienkriterien der Abbruch des Surveillance-Programms, bevor sich eine fortgeschrittene Krebserkrankung im Zusammenhang mit der Neoplasie entwickelt. Die Tumorenukleation und duodenumerhaltende Pankreaskopfresektion, entweder total oder partiell, sind parenchymsparende Resektionen bei benignen Neoplasien des Pankreaskopfs. Erste Wahl bei kleinen Tumoren ist die Enukleation; allerdings ist diese mit einem erhöhten Risiko für Pankreasfisteln von Grad B + C nach Pankreas-Hauptgangverletzung assoziiert. Vorteile der duodenumerhaltenden totalen oder partiellen Pankreaskopfresektion sind geringe operationsbedingte Komplikationen, eine Mortalität von < 0,5 % und die Aufrechterhaltung der endo- und exokrinen Pankreasfunktionen. Parenchymsparende Pankreaskopfresektionen sollten die klassischen Whipple-Operationen bei Neoplasien des Pankreaskopfs ablösen.

The increased detection of pancreatic cysts in recent years has triggered extensive diagnostic investigations to clarify their potential risk of malignancy, resulting in a large number of patients undergoing numerous imaging follow-up studies for many years. Therefore, there is a growing need for optimization of the current surveillance protocol to reduce both healthcare costs and waiting lists, while still maintaining appropriate sensibility and specificity. Imaging is an essential tool for evaluating patients with intraductal papillary mucinous neoplasms (IPMNs) since it can assess several predictors for malignancy and thus guide further management recommendations. Although contrast-enhanced magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) has been widely recommended by most international guidelines, recent results support the use of unenhanced abbreviated-MRI (A-MRI) protocols as a surveillance tool in patients with IPMN. In fact, A-MRI has shown high diagnostic performance in malignant detection, with high sensitivity and specificity as well as excellent interobserver agreement. The aim of this paper is, therefore, to discuss the current available evidence on whether the implementation of an abbreviated-MRI (A-MRI) protocol for cystic pancreatic lesion surveillance could improve healthcare economics and reduce waiting lists in clinical practice without significantly reducing diagnostic accuracy.

Benign and premalignant neoplasms of the pancreas are increasingly detected and recommended for surgical treatment. For tumors of the pancreatic head, the challenging decision is: multiorgan resection or local tumor extirpation? Compared with pancreaticoduodenectomy, duodenum-preserving pancreatic head resection is associated with significantly fewer surgery-related serious and severe complications and lower in-hospital mortality. The decisive advantage of duodenum-preserving pancreatic head resection is the maintenance of endocrine and exocrine pancreatic and upper gastrointestinal tract functions.

UNASSIGNED: The present experimental models of cystic diseases are not adequate and require further investigation.
UNASSIGNED: In this study, a new way of producing a tissue-mimicking model of cysts and cystic neoplasms was evaluated.
UNASSIGNED: To simulate cysts and cystic neoplasms, ex vivo rabbit normal bladders and VX2-implanted tumor bladders were produced, fixed, and embedded in agarose gel.
UNASSIGNED: 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.
UNASSIGNED: Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) software. The t-test was used for analyzing enumeration data.
UNASSIGNED: 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.
UNASSIGNED: 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.

Differentiating pancreatic cystic lesions (PCLs) remains a diagnostic challenge. The use of high-definition imaging modalities which detect tumor microvasculature have been described in solid lesions. We aim to evaluate the usefulness of cystic microvasculature when used in combination with cyst fluid biochemistry to differentiate PCLs.
We retrospectively analyzed 110 consecutive patients with PCLs from 2 Italian Hospitals who underwent EUS with H-Flow and EUS fine needle aspiration to obtain cystic fluid. The accuracy of fluid biomarkers was evaluated against morphological features on radiology and EUS. Gold standard for diagnosis was surgical resection. A clinical and radiological follow up was applied in those patients who were not resected because not surgical indication and no signs of malignancy were shown.
Of 110 patients, 65 were diagnosed with a mucinous cyst, 41 with a non-mucinous cyst, and 4 with an undetermined cyst. Fluid analysis alone yielded 76.7% sensitivity, 56.7% specificity, 77.8 positive predictive value (PPV), 55.3 negative predictive value (NPV) and 56% accuracy in diagnosing pancreatic cysts alone. Our composite method yielded 97.3% sensitivity, 77.1% specificity, 90.1% PPV, 93.1% NPV, 73.2% accuracy.
This new composite could be applied to the holistic approach of combining cyst morphology, vascularity, and fluid analysis alongside endoscopist expertise.

Microwave ablation (MWA) is a promising modality that needs to be further investigated for cystic lesions. The present study aimed to determine the effects of MWA on cysts and cystic neoplasms with a tissue-mimicking model.
Twenty New Zealand White rabbits were randomly divided into Group A (cyst mimic models, n = 10, φ = 5 cm) and Group B (cystic neoplasm mimicking models, n = 10, φ = 5 cm). For each group, ex vivo rabbit healthy bladder and VX2-implanted tumor bladder were fixed and embedded in agarose gel to mimic cyst and cystic neoplasm. In the MWA experimental subgroups, microwave antennas guided by computed tomography (CT) were introduced into these models. A system thermometer was placed at the outer edge of the bladder wall to monitor temperature changes. Immediately after MWA, ex vivo rabbit healthy bladders and VX2-implanted tumor bladders were harvested for gross anatomy and prepared for pathological evaluation.
A total of twenty cyst and cystic neoplasm mimicking models were successfully developed. Ninety percent of the MWA procedures were successful, and no peri-procedural complications were encountered. The temperature of the cystic wall increased with duration in both MWA experimental subgroups and an effective ablation temperature (>60 °C) was achieved. Pathological examination of the cyst and cystic neoplasm mimic models revealed degenerative necrosis of the bladder wall mucosal epithelial cells, loss of bladder wall tissue structure and coagulative necrosis of VX2 tumor cells.
Our data indicate that MWA could cause thermal damage to the tissue structure of cyst and cystic neoplasm, and it is an effective technique for treating cystic diseases.HIGHLIGHTSex vivo rabbit healthy bladder and VX2-implanted tumor bladder were fixed and embedded in agarose gel to mimic cyst and cystic neoplasm.The temperature of the cystic wall increased with MWA duration and an effective ablation temperature (> 60 °C) was achieved.MWA could cause thermal damage to the tissue structure of the cyst and cystic neoplasm and it is effective in treating cystic diseases, as assessed by histopathology.

Cystic mucinous neoplasms of urachal origin cover a wide spectrum of benign and malignant lesions arising from the remnants of the urachus. They display various degrees of tumor cell atypia and local invasion, with no reported cases of metastasis or recurrence after complete surgical resection. We present a 47-year-old man who referred to our Surgical Department due to an abdominal cystic mass incidentally found upon abdominal ultrasound. He underwent en block resection of the cystic mass along with partial bladder dome cystectomy. The histopathology of the resected specimen revealed a cystic mucinous epithelial tumor of low malignant potential with areas of intraepithelial carcinoma. The patient showed no evidence of disease recurrence or distant metastasis 6 months after resection and is scheduled for follow-up with serial MRI or CT scans and blood tumor markers over the next 5 years.

UNASSIGNED: Gastrointestinal stromal tumors (GISTs) are typically solid, sometimes with small cystic areas, but rarely manifest as predominantly cystic neoplasms. In addition, cystic intestinal GISTs with intratumoral abscess formation are rare.
UNASSIGNED: We present the case of a 49-year-old male patient with a history of frequent and urgent urination for 2 weeks. Radiologic studies revealed a large cystic mass in the lower abdomen. The patient underwent abdominal laparotomy, which revealed a large cystic mass arising from the distal ileum invading the sigmoid mesocolon and apex vesicae. Partial resection of the ileum along with the tumor and the adjacent bladder was performed. Macroscopic examination revealed that the cystic mass contained a large amount of foul-smelling pus and a tumor-bowel fistula. The final pathology revealed an abdominal stromal tumor. Postoperative recovery was uneventful, and adjuvant imatinib mesylate 400 mg was administered daily. No tumor recurrence or metastasis was observed during the 9-month follow-up period.
UNASSIGNED: Fingings of a cystic tumor in the abdomen should raise concern for cystic GISTs. This case report reviews a rare presentation of an ileal giant cystic GIST with atypical intratumoral abscess formation. Complete surgical resection and adjuvant imatinib is still the mainstay treatment for GISTs.