OSNA: A Fast Molecular Test Based on CK19 mRNA Concentration for Assessment of EBUS-TBNA Samples in Lung Cancer Patients

Sentinel Lymph Node Mapping in Lung Cancer: A Pilot Study for the Detection of Micrometastases in Stage I Non-Small Cell Lung Cancer

Lymphadenectomy represents a fundamental step in the staging and treatment of non-small cell lung cancer (NSCLC). To date, the extension of lymphadenectomy in early-stage NSCLC is a debated topic due to its possible complications. The detection of sentinel lymph nodes (SLNs) is a strategy that can improve the selection of patients in which a more extended lymphadenectomy is necessary. This pilot study aimed to refine lymph nodal staging in early-stage NSCLC patients who underwent robotic lung resection through the application of innovative intraoperative sentinel lymph node (SLN) identification and the pathological evaluation using one-step nucleic acid amplification (OSNA). Clinical N0 NSCLC patients planning to undergo robotic lung resection were selected. The day before surgery, all patients underwent radionuclide computed tomography (CT)-guided marking of the primary lung lesion and subsequently Single Photon Emission Computed Tomography (SPECT) to identify tracer migration and, consequently, the area with higher radioactivity. On the day of surgery, the lymph nodal radioactivity was detected intraoperatively using a gamma camera. SLN was defined as the lymph node with the highest numerical value of radioactivity. The OSNA amplification, detecting the mRNA of CK19, was used for the detection of nodal metastases in the lymph nodes, including SLN. From March to July 2021, a total of 8 patients (3 female; 5 male), with a mean age of 66 years (range 48-77), were enrolled in the study. No complications relating to the CT-guided marking or preoperative SPECT were found. An average of 5.3 lymph nodal stations were examined (range 2-8). N2 positivity was found in 3 out of 8 patients (37.5%). Consequently, pathological examination of lymph nodes with OSNA resulted in three upstages from the clinical IB stage to pathological IIIA stage. Moreover, in 1 patient (18%) with nodal upstaging, a positive node was intraoperatively identified as SLN. Comparing this protocol to the usual practice, no difference was found in terms of the operating time, conversion rate, and complication rate. Our preliminary experience suggests that sentinel lymph node detection, in association with the accurate pathological staging of cN0 patients achieved using OSNA, is safe and effective in the identification of metastasis, which is usually undetected by standard diagnostic methods.

CK19 Predicts Recurrence and Prognosis of HBV Positive HCC

BACKGROUND

Cytokeratin is associated with the recurrence and metastasis of some cancers and tends to increase the malignancy of the disease. It is getting more and more attention in cancer research. Abnormal expression of cytokeratin 19 (CK19) has been reported as an important prognostic factor in cancers. CK19 is a marker of bile duct cells, liver progenitor cells (HPCs), and early hepatoblasts, and its expression is associated with poor prognosis in patients diagnosed with hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the predictive value of CK19 for tumor recurrence after radical resection in patients with hepatitis B virus (HBV) positive HCC.

METHODS

This study was a retrospective study conducted in two institutions. A total of 674 patients with HBV positive HCC who underwent radical HCC resection from January 2010 to May 2020 were included in this study. Chi-square test or Fisher's exact test was used to compare the classification variables and continuous variables were compared by t-test or Wilcoxon rank sum test. Cox regression model was used for univariate and multi-variable survival analyses. Based on the results of the multi-variable analyses of Cox regression, the nomogram of 2-year recurrence-free survival (RFS) was plotted. The model was validated internally in the Hangzhou cohort (training set) and then externally in the Lanzhou cohort (test set) and the effectiveness of the model was tested.

RESULTS

For all 674 patients, 223 cases (33.1%) were positive and 451 cases (66.9%) were negative for CK19. The 2-year RFS rate was higher in patients with CK19 negative than in patients with CK19 positive. In the training set, correlation analysis showed that CK19 expression was correlated with preoperative potassium (P value(P) = 0.030), satellite nodules (P < 0.001) and microvascular invasion (P = 0.020). In the test set, CK19 expression was correlated with postoperative platelet (P = 0.038), satellite nodules (P = 0.003), microvascular invasion (P = 0.011), and maximum tumor size (P = 0.039). Univariate Cox regression correlation analyses showed that CK19 expression was correlated with preoperative potassium (P value(P) = 0.030), satellite nodules (P < 0.001), and microvascular invasion (P = 0.020). Training and test sets showed that postoperative platelet (> 300/L), CK19, satellite nodules in the training set, microvascular invasion, maximum tumor size, and tumor boundary were adverse factors for predicting RFS. Multi-variable analyses showed that in the training set, postoperative platelet > 300/L (hazard ratios (HR) = 2.753, 95% confidence interval (95%CI):1.234-6.142, P = 0.013), CK19 (HR = 1.410, 95%CI:1.006-1.976, P = 0.046), satellite nodule (HR = 1.476, 95%CI:1.026-2.120, P = 0.036), microvascular invasion (HR = 2.927, 95%CI:2.006-4.146, P < 0.001), incomplete tumor capsule (HR = 1.539, 95%CI:1.012-2.341, P = 0.044) were independent prognostic indicator of poor RFS. In the test set, postoperative platelet > 300/L (HR = 2.816, 95%CI:1.043-7.603, P = 0.041), CK19 (HR = 1.586, 95%CI:1.016-2.475, P = 0.042), satellite nodule (HR = 1.706, 95%CI:1.067-2.728, P = 0.026), microvascular invasion (HR = 1.611, 95%CI:1.034-2.510, P = 0.035), and tumor without capsule (HR = 1.870, 95%CI:1.120-3.120, P = 0.017) were independent prognostic indicators of poor RFS. The C-index for the nomogram was 0.698 (95%CI: 0.654-0.742) and the C-index for the test set was 0.670 (95%CI: 0.616-0.724). Both internal and external verification showed good results in identification and calibration.

CONCLUSION

CK19 plays a key role in tumor malignancy through overexpression and the expression of CK19 is an independent adverse factor affecting recurrence; therefore, CK19 can be used as a potential biomarker to predict adverse prognosis after surgery and adjuvant therapy in HCC patients.

CK7/CK19 index: A potential prognostic factor for postoperative intrahepatic cholangiocarcinoma patients

BACKGROUND AND OBJECTIVES

Frequently aberrant expression of cytokeratin 7 (CK7) and cytokeratin 19 (CK19) have been observed in several human cancers. In this retrospective study, we aimed at investigating the prognostic significance of CK7 and CK19 in intrahepatic cholangiocarcinoma (ICC).

METHODS

Immunohistochemistry was performed to assess CK7 and CK19 expression on tissue microarrays in training cohort enrolling 214 ICC patients and validation cohort comprising 108 ICC patients. Kaplan-Meier analysis, Cox's proportional hazards regression, and nomogram were applied to evaluate the prognostic significance of both CKs.

RESULTS

Both CK7 and CK19 expression were significantly up-regulated in ICC compared to their non-tumor counterparts, and positively correlated with aggressive tumor phenotypes, like lymph node metastasis and larger tumor size. Furthermore, high expression of either CK7 or CK19 predicted a significantly dismal postoperative survival. Integrated analysis of CK7 and CK19 expression was identified as a better indicator for survival probability. Notably, the nomogram integrating CK7/CK19 index had a perfect prognostic performance as compared with current staging systems. The results were further confirmed in the validation cohort.

CONCLUSIONS

CK7/CK19 index was an independent adverse prognostic factor for ICC patients' survival, and may be helpful to improve postoperative risk stratification and individualized treatment strategies.

A more sensitive detection of micrometastases of NSCLC in lymph nodes using the one-step nucleic acid amplification (OSNA) method

BACKGROUND

Detection of tumor cells in lymph nodes (LNs) removed during the treatment of pulmonary tumor by radical surgery is limited by the possibilities of standard histopathological methods. The goal of this study was to obtain more accurate pTNM status by a more sensitive detection of micrometastases in LNs.

METHODS

A total of 885 LNs, an average of 13.8 LNs per patient, were removed during 64 surgeries. LNs from the same zone were pooled together as a group, five groups of LNs were examined in each patient. A total of 320 groups of LNs were examined. One-step nucleic acid amplification (OSNA) method was compared to standard histopathological examination with haematoxylin-eosin (H&E) staining and CK19 immunohistochemistry, specifically by an ultimate analysis of all intraoperatively removed LNs.

RESULTS

Identical results for H&E and OSNA examinations were recorded in 286 groups of LNs (89.4%). In total, positive examinations were recorded in 27 groups of LNs (8.4%) using the OSNA method, which were H&E negative. In seven groups of LNs (2.2%), the H&E examination was positive, while OSNA method produced negative results.

CONCLUSIONS

The OSNA examination led to a higher pTNM stage classification in 14 (21.9%) patients. The clinical significance remains the subject of follow-up research.

Interaction of cytokeratin 19 head domain and HER2 in the cytoplasm leads to activation of HER2-Erk pathway

HER2 is a receptor tyrosine kinase and its upregulation via activating mutations or amplification has been identified in some malignant tumors, including lung cancers. Because HER2 can be a therapeutic target in HER2-driven malignancies, it is important to understand the molecular mechanisms of HER2 activation. In the current study, we identified that cytokeratin 19 (KRT19) binds to HER2 at the inside face of plasma membrane. HER2 and KRT19, which were concurrently introduced to a human embryonic kidney 293 T cells, revealed an association with each other and resulted in phosphorylation of HER2 with the subsequent activation of a downstream Erk-associated pathway. A binding assay revealed that both the NH2-terminal head domain of KRT19 and the COOH-terminal domain of HER2 were essential for their binding. To investigate the impact of the interaction between HER2 and KRT19 in lung cancer, we examined their expressions and localizations in lung cancers. We found that KRT19 was highly expressed in HER2-positive lung cancer cells, and KRT19 and HER2 were co-localized at the cell membrane. In conclusion, we found that KRT19 intracellularly binds to HER2, playing a critical role in HER2 activation.

Endoscopic tattooing of early colon carcinoma enhances detection of lymph nodes most prone to harbor tumor burden

Background

Colorectal cancer (CRC) screening programs result in the detection of early-stage asymptomatic carcinomas suitable to be surgically cured. Lymph nodes (LN) from early CRC are usually small and may be difficult to collect. Still, at least 12 LNs should be analyzed from colectomies, to ensure a reliable pN0 stage. Presurgical endoscopic tattooing improves LN procurement. In addition, molecular detection of occult LN tumor burden in histologically pN0 CRC patients is associated with a decreased survival rate. We aimed to study the impact of presurgical endoscopic tattooing on the molecular detection of LN tumor burden in early colon neoplasms.

Methods

A prospective cohort study from a CRC screening-based population was performed at a tertiary academic hospital. LNs from colectomies with and without preoperative endoscopic tattooing were assessed by two methods, hematoxylin and eosin (HE), and RT-LAMP, to detect tumor cytokeratin 19 (CK19) mRNA. We compared the amount of tumor burden and LN yields from tattooed and non-tattooed specimens.

Results

HE and RT-LAMP analyses of 936 LNs were performed from 71 colectomies containing early carcinomas and endoscopically unresectable adenomas (8 pT0, 17 pTis, 27 pT1, 19 pT2); 47 out of 71 (66.2 %) were tattooed. Molecular positivity correlated with the presence of tattoo in LN [p < 0.001; OR 3.1 (95 % CI 1.7–5.5)]. A significantly higher number of LNs were obtained in tattooed specimens (median 17 LN vs. 14.5 LN; p = 0.019).

Conclusions

Endoscopic tattooing enables the analysis of those LNs most prone to harbor tumor cells and improves the number of LN harvested.

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-016-5026-3) contains supplementary material, which is available to authorized users.