Ablation of sensory neurons in a genetic model of pancreatic ductal adenocarcinoma slows initiation and progression of cancer.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an exuberant inflammatory desmoplastic response. The PDAC microenvironment is complex, containing both pro- and antitumorigenic elements, and remains to be fully characterized. Here, we show that sensory neurons, an under-studied cohort of the pancreas tumor stroma, play a significant role in the initiation and progression of the early stages of PDAC. Using a well-established autochthonous model of PDAC (PKC), we show that inflammation and neuronal damage in the peripheral and central nervous system (CNS) occurs as early as the pancreatic intraepithelial neoplasia (PanIN) 2 stage. Also at the PanIN2 stage, pancreas acinar-derived cells frequently invade along sensory neurons into the spinal cord and migrate caudally to the lower thoracic and upper lumbar regions. Sensory neuron ablation by neonatal capsaicin injection prevented perineural invasion (PNI), astrocyte activation, and neuronal damage, suggesting that sensory neurons convey inflammatory signals from Kras-induced pancreatic neoplasia to the CNS. Neuron ablation in PKC mice also significantly delayed PanIN formation and ultimately prolonged survival compared with vehicle-treated controls (median survival, 7.8 vs. 4.5 mo; P = 0.001). These data establish a reciprocal signaling loop between the pancreas and nervous system, including the CNS, that supports inflammation associated with oncogenic Kras-induced neoplasia. Thus, pancreatic sensory neurons comprise an important stromal cell population that supports the initiation and progression of PDAC and may represent a potential target for prevention in high-risk populations.

Gastric cancer in a situs inversus totalis patient with multiple intestinal and vessel variations related to gastrectomy surgery: A case report and literature review.

RATIONALE: Situs inversus totalis (SIT) is a rare congenital anomaly characterized by complete inversion of the abdominal and thoracic organs, and often involves multiple genetic mutations. The most suitable surgical technique for patients with multiple vessel and organ variations as well as SIT remains unclear. Furthermore, there has been insufficient clinical evidence that demonstrates which surgical techniques achieve the best outcomes. Finally, the standard of care has not yet been determined. We present the case of a 60-year-old man with SIT, who was diagnosed with moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction. We further describe the advantage of using robotic-assisted laparoscopic surgery in patients with this anomaly. PATIENT CONCERNS: A 60-year-old man complained of pain in his upper abdomen for 3 months. Physical examination revealed an apex beat in the right fifth intercostal space, and vascular anomalies were noted on abdominal angiographic computed tomography. DIAGNOSES: Moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction with SIT. INTERVENTIONS: Robot-assisted total gastrectomy with D2 lymph node dissection and hand-sewn Roux-en-Y anastomosis was performed. OUTCOMES: The postoperative course was uneventful, and the patient was discharged on the seventh postoperative day. LESSONS: Robotic surgery for gastric cancer is a safe and feasible alternative to laparoscopic surgery and it can be successfully used to treat gastric cancer in patients with SIT with multiple anatomic variations. As exemplified by our case, SIT might be accompanied by multiple anatomic variations. Detailed preoperative detailed imaging of the blood vessels and gastrointestinal tract is useful in these patients.

Hereditary diffuse gastric cancer - pathophysiology and clinical management.

Hereditary Diffuse Gastric Cancer is an autosomal dominant inherited gastric cancer syndrome caused by germline alterations in CDH1 (E-cadherin) and CTNNA1 (alpha-E-catenin) genes. Germline CDH1 alterations encompass small frameshifts, splice-site, nonsense, and missense mutations, as well as large rearrangements. Most CDH1 truncating mutations are pathogenic, and several missense CDH1 mutations have a deleterious effect on E-cadherin function. CDH1 testing should be performed in probands. Screening of at-risk individuals is indicated from the age of consent following counselling with a multidisciplinary team. In mutation-positive individuals prophylactic gastrectomy is recommended. Endoscopic surveillance is an option for those refusing/postponing gastrectomy, those with mutations of undetermined significance, and in CDH1-negative families. Ongoing research focus on the search of genetic causes other than CDH1 or CTNNA1 germline defects; assessment of the pathogenicity and penetrance of CDH1 missense mutations and identification of somatic mechanisms behind the progression from early (indolent) lesions to invasive (lethal) carcinomas.