BackgroundLiquid biopsies enable the detection of circulating tumor DNA (ctDNA). However, the clinical significance of KRAS-mutated ctDNA for pancreatic cancer has been inconsistent with respect to its prognostic and predictive potential.Methods and findingsA total of 422 blood samples were collected from 78 patients undergoing treatments for localized and metastatic pancreatic ductal adenocarcinoma. KRAS mutation in tissues and KRAS ctDNA levels in plasma were determined by RASKET and droplet digital polymerase chain reaction. Longitudinal monitoring of KRAS ctDNA was performed to assess its significance for predicting recurrence and prognosis and for evaluating therapeutic responses to chemotherapy compared with carbohydrate antigen 19–9 (CA19-9). In 67 tumor tissues, discrepancies in point mutations of KRAS were rarely observed among individual patients, implying that one targeted point mutation of KRAS can be determined in tumor tissues prior to longitudinal blood monitoring. One-time blood assessment of KRAS-mutated ctDNA before surgery or chemotherapy was not clearly associated with recurrence and prognosis. Sequential blood monitoring was performed in 39 patients who underwent surgery for potentially resectable tumors. Increased CA19-9 levels were significantly associated with recurrence, but not prognosis (P<0.001, P = 1.0, respectively), whereas emergence of KRAS ctDNA was significantly associated with prognosis (P<0.001) regardless of recurrence. Furthermore, in 39 patients who did not undergo surgery, detection of KRAS ctDNA was a predictive factor for prognosis (P = 0.005). Multivariate analysis revealed that detection of KRAS ctDNA was the only independent prognostic factor regardless of tumor resection (hazard ratios = 54.5 for patients who underwent surgery and 10.1 for patients who did not undergo surgery; P<0.001 for both). Patients without emergence of KRAS ctDNA within 1 year after surgery showed significantly better prognosis irrespective of recurrence (P<0.001). No detection or disappearance of KRAS ctDNA within 6 months of treatment was significantly correlated with therapeutic responses to first-line chemotherapy (P<0.001). Changes in KRAS status provided critical information for the prediction of therapeutic responses.ConclusionsOur study showed for the first time that detection of KRAS ctDNA levels within a short period enables the prediction of prognosis and therapeutic responses in patients with pancreatic cancer.
A 43-year-old otherwise healthy woman was found to have a retroperitoneal mass during a routine medical examination and was referred for further evaluation. Abdominal CT scan showed a well-delineated, low-density area that exhibited heterogeneous contrast enhancement. The area measured about 20 mm in size and was to the left of the aorta at the level of the inferior mesenteric artery. MRI showed a mass with heterogeneous hypointensity on T -weighted images and heterogeneous hyperintensity on T -weighted images. PET-CT scan showed slightly increased F-fluorodeoxyglucose accumulation within the mass. Laparoscopic resection was performed. A smooth, brownish mass was seen in the retroperitoneum and was resected with minimal blood loss. Histopathological examination showed a nodular mass measuring 40 × 26 × 20 mm that was composed solely of ectopic thyroid tissue. This case shows the exceptional development of ectopic thyroid in the infradiaphragmatic retroperitoneum and demonstrates the usefulness of laparoscopy for resecting such masses.
Patients with breast cancer who undergo surgery have a risk of developing multiple cancers in the contralateral breast and other organs. We previously reported that overexpression of satellite alpha transcripts (SAT) facilitates chromosomal instability, which is involved in the development of multiple tumors in patients with colorectal and gastric cancer. In this study, we elucidated the significance of SAT in the development of multiple tumors in patients with breast cancer. Relative expression of SAT (rSAT) was calculated in normal and tumor tissues from 167 patients. In total, 27 patients developed bilateral breast cancer (BBC) and 27 patients showed multiple primary cancer (MPC), with patients with BBC and MPC showing higher rSAT levels in tumor tissues than those in patients with single breast cancer (SBC) (P=0.0312 and P=0.0420, respectively). Additionally, higher rSAT levels in tumor tissues from patients with BBC were a significant factor according to univariate analysis, and multivariate analysis showed that rSAT >1.5 was a significant predictor of MPC [hazard ratio (HR): 2.96; P=0.0243); however, we did not clarify the involvement of SAT in normal tissues. Excluding 71 patients with BRCA-related clinical features, rSAT levels were higher in patients with BBC and MPC than in patients with SBC in tumor tissues and normal tissues (P<0.05). Significant predictors according to univariate analysis included rSAT >1.5 in tumor tissues, rSAT >2.4 in normal tissues, and T <2, whereas those for multivariate analysis included rSAT >2.4 in normal tissues for BBC (HR: 22.7; P=0.00120) and MPC (HR: 13.0; P=0.00601). Our data indicated that patients with breast cancer and high rSAT levels in their breast tissues exhibit a 10-to 20-fold increased risk for the development of multiple cancers when harboring no BRCA-related clinical features.
Highlights
An anterior approach to inguinal hernia repair using laparoscopy is demonstrated.
This approach provides added advantage to recurrent inguinal hernia repair.
This approach can prevent nerve damage by reducing surgical dissection.
Laparoscopic confirmation assures complete coverage of all hernia defects.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.