The “K-Sign”—A Novel CT Finding Suggestive before the Appearance of Pancreatic Cancer

Pancreatic invasive ductal adenocarcinoma (PDAC) has a poor prognosis, and the detection of PDAC during the early stage is thought to improve prognosis. In this study, we retrospectively investigated pancreatic morphological abnormalities that lead to the early diagnosis of PDAC with computed tomography (CT) imaging. In total, 41 out of 308 patients diagnosed with pancreatic cancer between 2011 and 2017 in our institution were enrolled. As a control group for the group with pancreatic cancer, 4277 patients without pancreato-biliary diseases were enrolled. We retrospectively reviewed and analyzed the clinical data including patient characteristics, the clinical course and preoperative CT imaging with pancreatic morphological features. Out of 41 patients, 24 patients (58.5%) showed local K-shaped constriction of the pancreatic parenchyma “K-sign” on preoperative CT images. Eight patients (19.5%) showed localized fatty change. Out of 4277 control patients, seven patients (0.16%) showed K-sign. “K-sign” may be used for the early diagnosis of PDAC by CT imaging.

Three Curative Pancreatectomies for the Metachronous Appearance of Pancreatic Invasive Ductal Adenocarcinoma

We report a rare case of a patient who underwent 3 successful curative operations for the metachronous appearance of pancreatic cancer. In July 2007, a 54-year-old woman underwent pylorus-preserving pancreaticoduodenectomy. In March 2010, a tumor measuring 9 mm in diameter was detected in the tail of the pancreas on computed tomography (CT) and magnetic resonance imaging. The pancreas tail was subsequently resected while preserving the pancreatic body. In February 2011, CT revealed a cystic tumor measuring 2.5 cm in diameter in the remnant pancreatic body without any metastasis; therefore, total resection of the residual pancreas was performed in April 2011. The first resected tumor was histopathologically diagnosed as undifferentiated adenocarcinoma with osteoclast-like giant cells. Additionally, the third resected tumor had similar undifferentiated components. Contrarily, the second resected tumor was diagnosed as a well-differentiated tubular adenocarcinoma. We consider that the tumor from the third operation was an intra-pancreatic metastasis of the primary cancer and that the tumor from the second operation was the second primary cancer. The patient responded well with good control of surgical diabetes for 92 months since the last pancreatectomy. This case suggested that aggressive repeated resection for recurrent pancreatic invasive ductal adenocarcinoma is beneficial in limited cases.

Introducing the "K-Shaped Sign", A New Finding on CT to Detect Early-Stage Pancreatic Cancer

Background: Pancreatic invasive ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer mortality in Japan. The early diagnosis of pancreatic cancer, which will increase the number of patients with resectable tumors, is urgently needed. The purpose of the present study was to examine the earliest signs of pancreatic abnormalities on CT in order to facilitate the diagnosis and treatment of PDAC. Methods: Forty-one patients with pancreatic cancer and their 154 CTs were selected for the present study. We used the images that were acquired prior to the diagnosis and examined the pancreas in these images to observe serial changes in the morphology of the pancreas after selecting CT images in which PDAC was suspected. We also confirmed whether the main pancreatic duct was observed around that area of the pancreas. Four thousand two hundred seventy-seven patients without pancreato-biliary disease with 4630 CTs were selected for the control group. Results: Two pancreas shapes were detected: localized constriction of the pancreatic parenchyma referred to as the K-shaped sign, and localized fatty changes. Twenty-four (58.5%) of 41 patients showed the K-shaped sign. The main pancreatic duct without dilatation was noted around the K-shaped sign in 9 of the 24 patients. Eight of 41 patients (19.5%) showed localized fatty changes. Nine of 41 patients (21.9%) showed no abnormality. In the control group, only seven of 4277 patients (0.16%) showed the K-shaped sign. Conclusions: The K-shaped sign including localized fatty changes is the earliest CT sign that presents with pancreatic abnormalities. The K-shaped sign does not indicate PDAC itself but may predict its future development.

Liquid Biopsy Prevents Inaccurate Her2 Status Determination by in situ Hybridization in a Patient with Invasive Ductal Adenocarcinoma of the Breast: Case Report

Utilization of circulating tumor DNA as a novel and noninvasive test for diagnosis confirmation, therapy selection, and cancer surveillance is a rapidly growing area of interest. In the wake of FDA approval of a liquid biopsy test, it is important for clinicians to acknowledge the obvious clinical utility of liquid biopsy for cancer management throughout the course of the disease. This case report describes a female with invasive ductal adenocarcinoma of the breast, where liquid biopsy was instrumental for her cancer characterization and personalized therapy selection.