Oncologic Staging with 68Ga-FAPI PET/CT Demonstrates a Lower Rate of Nonspecific Lymph Node Findings Than 18F-FDG PET/CT

Nonspecific lymph node uptake on 18F-FDG PET/CT imaging is a significant pitfall for tumor staging. Fibroblast activation protein α expression on cancer-associated fibroblasts and some tumor cells is less sensitive to acute inflammatory stimuli, and fibroblast activation protein-directed PET may overcome this limitation. Methods: Eighteen patients from our prospective observational study underwent 18F-FDG and 68Ga fibroblast activation protein inhibitor (FAPI) PET/CT scans within a median of 2 d (range, 0-22 d). Lymph nodes were assessed on histopathology and compared with SUV measurements. Results: On a per-patient basis, lymph nodes were rated malignant in 10 (56%) versus 7 (39%) patients by 18F-FDG PET/CT versus 68Ga-FAPI PET/CT scans, respectively, with a respective accuracy of 55% versus 94% for true lymph node metastases. Five of 6 (83%) false-positive nodes on the 18F-FDG PET/CT scans were rated true negative by the 68Ga-FAPI PET/CT scans. On a per-lesion basis, tumor detection rates were similar (85/89 lesions, 96%). Conclusion: 68Ga-FAPI PET/CT imaging demonstrated higher accuracy for true nodal involvement and therefore has the potential to replace 18F-FDG PET/CT imaging for cancer staging.

Histology of the Primary Tumor Correlates with False Positivity of Integrated 18F-FDG-PET/CT Lymph Node Staging in Resectable Lung Cancer Patients

This study aimed to evaluate the diagnostic accuracy and false positivity rate of lymph node (LN) staging assessed by integrated 18F-fluorodeoxyglucose positron emission computed tomography (18F-FDG-PET/CT) in patients with operable lung cancer to the tumor histology. In total, 129 consecutive patients with non-small-cell lung cancer (NSCLC) undergoing anatomical lung resections were included. Preoperative LN staging was evaluated in the relationship to the histology of the resected specimens (group 1: lung adenocarcinoma/LUAD; group 2: squamous cell carcinoma/SQCA). Statistical analysis was performed by the Mann-Whitney U-test, the chi² test, and binary logistic regression analysis. To establish an easy-to-use algorithm for the identification of LN false positivity, a decision tree including clinically meaningful parameters was generated. In total, 77 (59.7%) and 52 (40.3%) patients were included in the LUAD and SQCA groups, respectively. SQCA histology, non-G1 tumors, and tumor SUVmax > 12.65 were identified as independent predictors of LN false positivity in the preoperative staging. The corresponding ORs and their 95% CIs were 3.35 [1.10-10.22], p = 0.0339; 4.60 [1.06-19.94], p = 0.0412; and 2.76 [1.01-7.55], and p = 0.0483. The preoperative identification of false-positive LNs is an important aspect of the treatment regimen for patients with operable lung cancer; thus, these preliminary findings should be further evaluated in larger patient cohorts.

Multiresolution nondestructive 3D pathology of whole lymph nodes for breast cancer staging

SIGNIFICANCE

For breast cancer patients, the extent of regional lymph node (LN) metastasis influences the decision to remove all axillary LNs. Metastases are currently identified and classified with visual analysis of a few thin tissue sections with conventional histology that may underrepresent the extent of metastases.

AIM

We sought to enable nondestructive three-dimensional (3D) pathology of human axillary LNs and to develop a practical workflow for LN staging with our method. We also sought to evaluate whether 3D pathology improves staging accuracy in comparison to two-dimensional (2D) histology.

APPROACH

We developed a method to fluorescently stain and optically clear LN specimens for comprehensive imaging with multiresolution open-top light-sheet microscopy. We present an efficient imaging and data-processing workflow for rapid evaluation of H&E-like datasets in 3D, with low-resolution screening to identify potential metastases followed by high-resolution localized imaging to confirm malignancy.

RESULTS

We simulate LN staging with 3D and 2D pathology datasets from 10 metastatic nodes, showing that 2D pathology consistently underestimates metastasis size, including instances in which 3D pathology would lead to upstaging of the metastasis with important implications on clinical treatment.

CONCLUSIONS

Our 3D pathology method may improve clinical management for breast cancer patients by improving staging accuracy of LN metastases.

Role of surgery following neoadjuvant chemoradiation in patients with lymph node positive locally advanced esophageal adenocarcinoma: a national cancer database analysis

Background

Concurrent chemoradiation (CRT) followed by surgery is a standard of care for locally advanced esophageal adenocarcinoma. It remains unclear if surgery following CRT offers any meaningful survival benefit compared to CRT alone in patients with clinical N3 disease who are at the highest risk of developing distant disease relapse.

Methods

We conducted analysis of the National Cancer Database (NCDB) to compare overall survival (OS) of patients with locally advanced esophageal adenocarcinoma (cTanyN1-3M0 based on AJCC 7th staging system) who underwent CRT with or without surgery and analyzed outcomes based on the cN stage.

Results

7,520 patients were included in the analysis-74.7% had cN1 disease, 21.1% had cN2 disease, and 4.3% had cN3 disease. The median OS advantage offered by CRT followed by surgery was 22, 15.8, and 9.6 months compared to CRT alone in cN1, cN2, and cN3 patients, respectively. The 5-year OS estimates in the surgical group were 36.9%, 31.6% and 15.9% in cN1, cN2 and cN3 groups, respectively.

Conclusions

Surgery following CRT in patients with locally advanced esophageal adenocarcinoma leads to improvement in OS, with the largest benefit noted in patients with cN1 and cN2 disease. Surgery following CRT also confers meaningful long-term survival advantage for a subset of cN3 patients.

Intra- and Interobserver Variability in Magnetic Resonance Imaging Measurements in Rectal Cancer Patients

Colorectal cancer is the second most common cancer in Europe, and accurate lymph node staging in rectal cancer patients is essential for the selection of their treatment. MRI lymph node staging is complex, and few studies have been published regarding its reproducibility. This study assesses the inter- and intraobserver variability in lymph node size, apparent diffusion coefficient (ADC) measurements, and morphological characterization among inexperienced and experienced radiologists. Four radiologists with different levels of experience in MRI rectal cancer staging analyzed 36 MRI scans of 36 patients with rectal adenocarcinoma. Inter- and intraobserver variation was calculated using interclass correlation coefficients and Cohens-kappa statistics, respectively. Inter- and intraobserver agreement for the length and width measurements was good to excellent, and for that of ADC it was fair to good. Interobserver agreement for the assessment of irregular border was moderate, heterogeneous signal was fair, round shape was fair to moderate, and extramesorectal lymph node location was moderate to almost perfect. Intraobserver agreement for the assessment of irregular border was fair to substantial, heterogeneous signal was fair to moderate, round shape was fair to moderate, and extramesorectal lymph node location was substantial to almost perfect. Our data indicate that subjective variables such as morphological characteristics are less reproducible than numerical variables, regardless of the level of experience of the observers.

Magnetic Resonance Imaging Evaluation of the Accuracy of Various Lymph Node Staging Criteria in Rectal Cancer: A Systematic Review and Meta-Analysis

Background

Magnetic resonance imaging (MRI)-based lymph node staging remains a significant challenge in the treatment of rectal cancer. Pretreatment evaluation of lymph node metastasis guides the formulation of treatment plans. This systematic review aimed to evaluate the diagnostic performance of MRI in lymph node staging using various morphological criteria.

Methods

A systematic search of the EMBASE, Medline, and Cochrane databases was performed. Original articles published between 2000 and January 2021 that used MRI for lymph node staging in rectal cancer were eligible. The included studies were assessed using the QUADAS-2 tool. A bivariate random-effects model was used to conduct a meta-analysis of diagnostic test accuracy.

Results

Thirty-seven studies were eligible for this meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio of preoperative MRI for the lymph node stage were 0.73 (95% confidence interval [CI], 0.68–0.77), 0.74 (95% CI, 0.68–0.80), and 7.85 (95% CI, 5.78–10.66), respectively. Criteria for positive mesorectal lymph node metastasis included (A) a short-axis diameter of 5 mm, (B) morphological standard, including an irregular border and mixed-signal intensity within the lymph node, (C) a short-axis diameter of 5 mm with the morphological standard, (D) a short-axis diameter of 8 mm with the morphological standard, and (E) a short-axis diameter of 10 mm with the morphological standard. The pooled sensitivity/specificity for these criteria were 75%/64%, 81%/67%, 74%/79%, 72%/66%, and 62%/91%, respectively. There was no significant difference among the criteria in sensitivity/specificity. The area under the receiver operating characteristic (ROC) curve values of the fitted summary ROC indicated a diagnostic accuracy rate of 0.75–0.81.

Conclusion

MRI scans have minimal accuracy as a reference index for pretreatment staging of various lymph node staging criteria in rectal cancer. Multiple types of evidence should be used in clinical decision-making.

Pre-Operative Prediction of Mediastinal Node Metastasis Using Radiomics Model Based on 18F-FDG PET/CT of the Primary Tumor in Non-Small Cell Lung Cancer Patients

Purpose: We investigated whether a fluorine-18-fluorodeoxy glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT)-based radiomics model (RM) could predict the pathological mediastinal lymph node staging (pN staging) in patients with non-small cell lung cancer (NSCLC) undergoing surgery.

Methods: A total of 716 patients with a clinicopathological diagnosis of NSCLC were included in this retrospective study. The prediction model was developed in a training cohort that consisted of 501 patients. Radiomics features were extracted from the ¹⁸F-FDG PET/CT of the primary tumor. Support vector machine and extremely randomized trees were used to build the RM. Internal validation was assessed. An independent testing cohort contained the remaining 215 patients. The performances of the RM and clinical node staging (cN staging) in predicting pN staging (pN0 vs. pN1 and N2) were compared for each cohort. The area under the curve (AUC) of the receiver operating characteristic curve was applied to assess the model's performance.

Results: The AUC of the RM [0.81 (95% CI, 0.771–0.848); sensitivity: 0.794; specificity: 0.704] for the predictive performance of pN1 and N2 was significantly better than that of cN in the training cohort [0.685 (95% CI, 0.644–0.728); sensitivity: 0.804; specificity: 0.568], (P-value = 8.29e-07, as assessed by the Delong test). In the testing cohort, the AUC of the RM [0.766 (95% CI, 0.702–0.830); sensitivity: 0.688; specificity: 0.704] was also significantly higher than that of cN [0.685 (95% CI, 0.619–0.747); sensitivity: 0.799; specificity: 0.568], (P = 0.0371, Delong test).

Conclusions: The RM based on ¹⁸F-FDG PET/CT has a potential for the pN staging in patients with NSCLC, suggesting that therapeutic planning could be tailored according to the predictions.

Ultrastaging Using Ex Vivo Sentinel Lymph Node Mapping and One-Step Nucleic Acid Amplification (OSNA) in Gastric Cancer: Experiences of a European Center

Simple Summary

In this study, the effectiveness of One-step nucleic acid amplification (OSNA) in combination with ex vivo SLN mapping is compared with conventional histology including immunohistochemistry. OSNA lymph node evaluation has been performed in 41 gastric cancer cases. It showed a high effectiveness with sensitivity, specificity, and accuracy rates of 85.4%, 93.5%, and 92.4%, respectively The LN status could be predicted in 40 cases and led to upstaging in three cases (14%). The OSNA method proved its potential to increase the sensitivity of metastases detection.

Abstract

Background: In this study, the effectiveness of One-step nucleic acid amplification (OSNA) in combination with ex vivo SLN mapping is compared with conventional histology including immunohistochemistry. Methods: LNs were retrieved from gastrectomy specimens in an unfixed state. After ex vivo SLN mapping using methylene-blue, LNs were sliced to provide samples for histology and OSNA. Results: In total, 334 LNs were retrieved in the fresh state from 41 patients. SLN detection was intended in 40 cases but was successful in only 29, with a correct LN status prediction in 23 cases (79%). Excluding one case out of 41 with a failure likely caused by a processing error, OSNA showed a high effectiveness with sensitivity, specificity, and accuracy rates of 85.4%, 93.5%, and 92.4%, respectively. The LN status could be predicted in all but one case, in which the single positive LN was not eligible for OSNA testing. Moreover, OSNA evaluation led to upstaging from N0 to N+ in three cases (14%). Conclusion: The ex vivo SLN protocol used resulted in a relatively poor detection rate. However, the OSNA method was not hampered by this detection rate and proved its potential to increase the sensitivity of metastases detection.

CA19.9 Serum Level Predicts Lymph-Nodes Status in Resectable Pancreatic Ductal Adenocarcinoma: A Retrospective Single-Center Analysis

Background

The choice between upfront surgery or neoadjuvant treatments (NAT) for resectable pancreatic ductal adenocarcinoma (R-PDAC) is controversial. R-PDAC with potential nodal involvement could benefit from NT. Ca (Carbohydrate antigen) 19.9 and serum albumin levels, alone or in combination, have proven their efficacy in assessing PDAC prognosis. The objective of this study was to evaluate the role of Ca 19.9 serum levels in predicting nodal status in R-PDAC.

Methods

Preoperative Ca 19.9, as well as serum albumin levels, of 165 patients selected for upfront surgery have been retrospectively collected and correlated to pathological nodal status (N), resection margins status (R) and vascular resections (VR). We further performed ROC curve analysis to identify optimal Ca 19.9 cut-off for pN+, R+ and vascular resection prediction.

Results

Increased Ca 19.9 levels in 114 PDAC patients were significantly associated with pN+ (p <0.001). This ability, confirmed in all the series by ROC curve analysis (Ca 19.9 ≥32 U/ml), was lost in the presence of hypoalbuminemia. Furthermore, Ca 19.9 at the cut off >418 U/ml was significantly associated with R+ (87% specificity, 36% sensitivity, p 0.014). Ca 19.9, at the cut-off >78 U/ml, indicated a significant trend to predict the need for VR (sensitivity 67%, specificity 53%; p = 0.059).

Conclusions

In R-PDAC with normal serum albumin levels, Ca 19.9 predicts pN+ and R+, thus suggesting a crucial role in deciding on NAT.

The role of pre-biopsy mpMRI in lymph node staging for prostate cancer

INTRODUCTION

Prostate cancer (PCa) staging is an integral part in the management of prostate cancer. The gold standard for diagnosing lymph node invasion is a surgical lymphadenectomy, with no superior imaging modality available at the clinician's disposal. Our aim in this study is to identify if a pre-biopsy multiparametric MRI (mpMRI) can provide enough information about pelvic lymph nodes in intermediate and high risk PCa patients, and whether it can substitute further cross sectional imaging (CSI) modalities of the abdomen and pelvis in these risk categories.

METHODS

Patients with intermediate and high risk prostate cancer were collected between January 2015 and June 2019, while excluding patients who did not undergo a pre-biopsy mpMRI or a CSI. Date regarding biopsy result, PSA, MRI results, CSI imaging results were collected. Using Statistical Package for the Social Sciences (SPSS) version 24.0, statistical analysis was conducted using the Cohen's Kappa agreement for comparison of mpMRI with CSI. McNemar's test and receiver operator curve (ROC) curve were used for comparison of sensitivity of both tests when comparing to the gold standard of lymphadenectomy.

RESULTS

A total of 143 patients fit the inclusion criteria. We further stratified our patients into according to PSA level and Gleason score. Overall, agreement between mpMRI and all CSI was 0.857. When stratifying patients based on Gleason score and PSA, the higher the grade or PSA, the higher agreement between mpMRI and CSI. The sensitivity of mpMRI (73.7%) is similar to CSI (68.4%). When comparing CSI sensitivity to that of mpMRI, no significant difference was present by utilizing the McNemar test and very similar receiver operating characteristic curve.

CONCLUSION

A pre-biopsy mpMRI can potentially substitute further cross sectional imaging in our cohort of patients. However, larger prospective studies are needed to confirm our findings.

18F-Fluciclovine Positron Emission Tomography in Prostate Cancer: A Systematic Review and Diagnostic Meta-Analysis

Background: to explore the diagnostic accuracy of 18F-Fluciclovine positron-emission tomography (PET) in prostate cancer (PCa), considering both primary staging prior to radical therapy, biochemical recurrence, and advanced setting. Methods: A systematic web search through Embase and Medline was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies performed from 2011 to 2020 were evaluated. The terms used were “PET” or “positron emission tomography” or “positron emission tomography/computed tomography” or “PET/CT” or “positron emission tomography-computed tomography” or “PET-CT” and “Fluciclovine” or “FACBC” and “prostatic neoplasms” or “prostate cancer” or “prostate carcinoma”. Only studies reporting about true positive (TP), true negative (TN), false positive (FP) and false negative (FN) findings of 18F-fluciclovine PET were considered eligible. Results: Fifteen out of 283 studies, and 697 patients, were included in the final analysis. The pooled sensitivity for 18F-Fluciclovine PET/CT for diagnosis of primary PCa was 0.83 (95% CI: 0.80–0.86), the specificity of 0.77 (95% CI: 0.74–0.80). The pooled sensitivity for preoperative LN staging was 0.57 (95% CI: 0.39–0.73) and specificity of 0.99 (95% CI: 0.94–1.00). The pooled sensitivity for the overall detection of recurrence in relapsed patients was 0.68 (95% CI: 0.63–0.73), and specificity of 0.68 (95% CI: 0.60–0.75). Conclusion: This meta-analysis showed promising results in term of sensitivity and specificity for 18F-Fluciclovine PET/CT to stage the primary lesion and in the assessment of nodal metastases, and for the detection of PCa locations in the recurrent setting. However, the limited number of studies and the broad heterogeneity in the selected cohorts and in different investigation protocols are limitation affecting the strength of these results.

Comparison of three lymph node staging methods for predicting outcome in breast cancer patients with mastectomy

Background

Axillary lymph node (ALN) staging is essential in predicting the clinical outcome of breast cancer (BC) patients. Traditionally, it follows the tumor-node-metastasis (TNM) staging, but its accuracy needs further improvement.

Methods

A total of 9,616 BC patients from the Surveillance, Epidemiology, and End Results (SEER) database and 675 patients from the First Affiliated Hospital of China Medical University underwent mastectomy together with ALN dissection were reviewed. Univariate and multivariate logistic analyses were conducted to find the most meaningful factors relevant to prognosis.

Results

After univariate and multivariate analyses, age, race, primary site, radiation, chemotherapy, grade, T-stage, estrogen receptor (ER), progesterone receptor (PR), total number of positive lymph nodes (pN), positive lymph node ratio (LNR) and log odds of positive LNs (LODDS) were found to be significantly associated with overall survival (OS). Using these non-LN risk factors, we further compared the efficacy of three different ALN staging methods in prognosis via nomograms. Harrell's concordance index (C-index) and Akaike Information Criterion (AIC) were used to measure nomogram performance of the ALN staging methods: pN: C-index=0.687 (95% CI: 0.678-0.696), AIC =61,398.24; LNR: C-index =0.691 (95% CI: 0.683-0.701), AIC =61,313.56; and LODDS: C-index =0.691 (95% CI: 0.682-0.700), AIC =61,315.60. We found that the nomogram incorporating LODDS had better predictive ability compared with other two methods. Furthermore, an external validation revealed a C-index of 0.753 (95% CI: 0.690-0.816) for the Asian population, which indicates the nomogram based on LODDS may have universality for both Western and Asian populations.

Conclusions

Compared with pN and LNR, LODDS showed higher homeostasis in LN evaluation, and showed marked efficacy in evaluating survival differences among patients with negative LN staging. We constructed a BC prognosis model by incorporating highly relevant clinical pathological factors and a new method of LN staging, which may greatly aid in guiding postoperative treatment.

Diagnostic Accuracy of 18F-PSMA-1007 PET/CT Imaging for Lymph Node Staging of Prostate Carcinoma in Primary and Biochemical Recurrence

Prostate-specific membrane antigen (PSMA)-ligand PET/CT is performed on patients with prostate cancer to stage the disease initially or to identify sites of recurrence after definitive therapy. On the basis of clinical results, ¹⁸F-PSMA-1007 is a promising PSMA PET tracer, but detailed histologic confirmation has been lacking. Methods: Ninety-six patients with prostate cancer underwent ¹⁸F-PSMA-1007 PET/CT followed by either radical prostatectomy with lymphadenectomy or salvage lymphadenectomy. The histologic findings of PSMA PET-positive nodes were analyzed retrospectively. A lesion-based and patient-based analysis was performed comparing all positive lesions and only lesions larger than 3 mm on histopathology. Results: Of the patients, 90.6% received ¹⁸F-PSMA-1007 PET/CT for staging before the primary treatment, whereas 9.4% underwent imaging for biochemical recurrence. In 34.4% of the cohort, positive lymph nodes were present on imaging. In total, 1,746 lymph nodes were dissected in 96 patients. ¹⁸F-PSMA-1007 PET had a lesion-based sensitivity of 81.7%, a specificity of 99.6%, a positive predictive value of 92.4%, and a negative predictive value of 98.9% for detecting positive lymph nodes larger than 3 mm. In the analysis of all malignant nodes regardless of size, the overall sensitivity, specificity, positive predictive value, and negative predictive value on lesion-based analysis were 71.2%, 99.5%, 91.3%, and 97.9%, respectively. The patient-based analysis showed a sensitivity of 85.9% and a specificity of 99.5% for lymph nodes larger than 3 mm. Conclusion: ¹⁸F-PSMA-1007 PET/CT reliably detects malignant lymph nodes and has an exceptional specificity of more than 99% for nodal metastases.

Quantitative metastatic lymph node burden and survival in Merkel cell carcinoma

BACKGROUND

Current lymph node (LN) staging for Merkel cell carcinoma (MCC) does not account for the number of metastatic LNs, which is a primary driver of survival in multiple cancers.

OBJECTIVE

To determine the impact of the number of metastatic LNs on survival in MCC.

METHODS

Patients with MCC undergoing surgery were identified from the National Cancer Database (NCDB). The association between metastatic LN number and survival was modeled with restricted cubic splines. A novel nodal classification system was derived by using recursive partitioning analysis. MCC patients undergoing surgery in the Surveillance, Epidemiology, and End Results (SEER) Program were used as validation cohort.

RESULTS

Among 3670 patients in the NCDB, increasing metastatic LN number was associated with decreased survival (P < .001). Mortality risk increased continuously with each additional positive LN when using multivariable, nonlinear modeling. According to a novel staging system derived via recursive partitioning analysis, the hazard ratio for death in multivariable regression compared with patients without LN involvement was 1.24 (P = .049), 2.08 (P < .001), 3.24 (P < .001), and 6.13 (P < .001) for the proposed N1a (1-3 metastatic LNs with microscopic detection), N1b (1-3 metastatic LNs with macroscopic detection), N2 (4-8 metastatic LNs), and N3 (≥9 metastatic LNs), respectively. This system was validated in the SEER cohort and showed improved concordance compared with the American Joint Committee on Cancer, Eighth Edition.

LIMITATIONS

Retrospective design.

CONCLUSIONS

Number of metastatic LNs is the dominant nodal factor driving survival in patients with MCC.

MRI-based guidelines for selective neoadjuvant treatment in rectal cancer: Does MRI adequately predict the indication for radiotherapy in daily practice in a large teaching hospital

OBJECTIVES

According to new Dutch guidelines for rectal cancer, MRI-defined tumour stage determines whether preoperative radiotherapy is indicated. Therefore, we sought to evaluate if preoperative MRI accurately predicts the indication for neoadjuvant treatment in rectal cancer cases in daily practice according to the new Dutch guidelines.

METHODS

Data for all rectal cancer patients who underwent mesorectal excision in our hospital, between January 2011 and January 2018 were collected retrospectively. We compared histopathologic outcome with tumour staging on preoperative MRI for patients who received no radiotherapy prior to resection or short-course radiotherapy directly followed by resection.

RESULTS

Of 223 patients treated according to the old guidelines, 94% received neoadjuvant therapy. Of 301 patients treated according to the new guidelines, only 49% did. Under the old guidelines, MRI predicted lymph node metastases with a sensitivity of 74.2% and a specificity of 52.6%. With the new guidelines, sensitivity was 47.5% and specificity was 77.3%. The new guidelines resulted in 45% more patients not being exposed to disadvantages of radiotherapy, but 13% of all patients were undertreated.

CONCLUSIONS

Concordance between clinical lymph node staging on preoperative MRI and histopathologic staging is limited, resulting in many rectal cancer patients not receiving adequate neoadjuvant therapy.

Noninvasive detection of cancer spread to lymph nodes: A review of molecular imaging principles and protocols

Identification of cancer spread to tumor-draining lymph nodes offers critical information for guiding treatment in many cancer types. Current clinical methods of nodal staging are invasive and can have substantial negative side effects. Molecular imaging protocols have long been proposed as a less invasive means of nodal staging, having the potential to enable highly sensitive and specific evaluations. This review article summarizes the current status and future perspectives for molecular targeted nodal staging.

Comparative Analysis of Clinical and Pathological Lymph Node Staging Data in Head and Neck Squamous Cell Carcinoma Patients Treated at the General Hospital Vienna

Background

Results from publications evaluating discrepancies between clinical staging data in relation to pathological findings demonstrate that a significant number of head and neck squamous cell carcinoma (HNSCC) patients are not correctly staged. The aim of this retrospective study was to analyze potential discrepancies of radiological assessment versus pathological data of regional lymph node involvement and to compare the results with data published in the literature.

Patients and methods

In a retrospective analysis we focused on patients with HNSCC routinely treated by surgery plus postoperative radiotherapy between 2002 and 2012. For inclusion, complete pre-operative clinical staging information with lymph node status and patho-histological information on involved lymph node regions as well as survival outcome data were mandatory. We included 87 patients (UICC stage III-IV 90.8%) for which the aforementioned data obtained by CT or MRI were available. Overall survival rates were estimated by the Kaplan-Meier method. The Pearson correlation coefficient and Spearman's rank correlation coefficient (non-linear relationship) was calculated.

Results

Discrepancies at the level of overall tumour stage assessment were noticed in 27.5% of all cases. Thereof, 5.7% were assigned to patho-histological up-staging or down-staging of the primary tumour. At the lymph node level, 11.5% of the patients were downstaged, and 10.3% were upstaged.

Conclusions

The study showed that in approximately one-fifth (21.8%) of the patients, lymph node assessment by CT or MRI differs from the pathologic staging, an outcome that corresponds well with those published by several other groups in this field.

Metastatic lymph node ratio and Lauren classification are independent prognostic markers for survival rates of patients with gastric cancer

The long-term prognosis for patients with gastric cancer (GC) following radical resection remains poor. It is important to identify prognostic markers to predict survival. In the present retrospective study, the association between the metastatic lymph node ratio (rN) and the Lauren classification on predicting overall survival (OS) was investigated. Furthermore, a subgroup analysis was performed on the Lauren classification, using rN score as an independent prognostic marker. In total, 261 pathologically confirmed patients with GC were retrospectively reviewed. Kaplan-Meier curves and Cox's proportional hazards modeling were applied to analyze the OS of patients, and were utilized in the subgroup analysis. Receiver operating characteristic (ROC) curves were used to compare the accuracy of prognosis between the rN score and lymph node staging (N stage). The χ² test was used to analyze the association between the rN score and Lauren classification. Univariate survival and multivariate analysis demonstrated that the rN score and Lauren classification were significant prognostic markers for patients with GC. The ROC analysis confirmed that the rN score was more effective than N staging for OS prediction. Subgroup analysis indicated that rN was more accurate at predicting OS time in patients with diffuse type GC. The rN score and the Lauren classification were independent prognostic factors for the OS of patients with GC following radical resection, and the rN score was more accurate than the N stage for predicting the prognosis. Overall, the rN may be suitable as an independent predictor for OS in patients with diffuse type GC.

Anatomical location of metastatic lymph nodes: an indispensable prognostic factor for gastric cancer patients who underwent curative resection

BACKGROUND

Although the numeric-based lymph node (LN) staging was widely used in the worldwide, it did not represent the anatomical location of metastatic lymph nodes (MLNs) and not reflect extent of LN dissection. Therefore, in the present study, we investigated whether the anatomical location of MLNs was still necessary to evaluate the prognosis of node-positive gastric cancer (GC) patients.

METHODS

We reviewed 1451 GC patients who underwent radical gastrectomy in our institution between January 1986 and January 2008. All patients were reclassified into several groups according to the anatomical location of MLNs and the number of MLNs. The prognostic differences between different patient groups were compared and clinicopathologic features were analyzed.

RESULTS

In the present study, both anatomical location of MLNs and the number of MLNs were identified as the independent prognostic factors (p < .01). The patients with extraperigastric LN involvement showed a poorer prognosis compared with the perigastric-only group (p < .001). For the N1-N2 stage patients, the prognostic discrepancy was still observed among them when the anatomical location of MLNs was considered (p < .05). For the N3-stage patients, although the anatomical location of MLNs had no significant effect on the prognosis of these patients, the higher number of MLNs in the extraperigastric area was correlated with the unfavorable prognosis (p < .05).

CONCLUSION

The anatomical location of MLNs was an important factor influencing the prognostic outcome of GC patients. To provide more accurate prognostic information for GC patients, the anatomical location of MLNs should not be ignored.

Comparison of DWI and 18F-FDG PET/CT for assessing preoperative N-staging in gastric cancer: evidence from a meta-analysis

The diagnostic values of diffusion weighted imaging (DWI) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) for N-staging of gastric cancer (GC) were identified and compared. After a systematic search to identify relevant articles, meta-analysis was used to summarize the sensitivities, specificities, and areas under curves (AUCs) for DWI and PET/CT. To better understand the diagnostic utility of DWI and PET/CT for N-staging, the performance of multi-detector computed tomography (MDCT) was used as a reference. Fifteen studies were analyzed. The pooled sensitivity, specificity, and AUC with 95% confidence intervals of DWI were 0.79 (0.73–0.85), 0.69 (0.61–0.77), and 0.81 (0.77–0.84), respectively. For PET/CT, the corresponding values were 0.52 (0.39–0.64), 0.88 (0.61–0.97), and 0.66 (0.62–0.70), respectively. Comparison of the two techniques revealed DWI had higher sensitivity and AUC, but no difference in specificity. DWI exhibited higher sensitivity but lower specificity than MDCT, and ¹⁸F-FDG PET/CT had lower sensitivity and equivalent specificity. Overall, DWI performed better than ¹⁸F-FDG PET/CT for preoperative N-staging in GC. When the efficacy of MDCT was taken as a reference, DWI represented a complementary imaging technique, while ¹⁸F-FDG PET/CT had limited utility for preoperative N-staging.

DWI for Assessment of Rectal Cancer Nodes After Chemoradiotherapy: Is the Absence of Nodes at DWI Proof of a Negative Nodal Status? AJR Am J Roentgenol. 2017;208:W79-W84. [PMID: 27959622 DOI: 10.2214/ajr.16.17117]

OBJECTIVE

When considering organ preservation in patients with rectal cancer with good tumor response, assessment of a node-negative status after chemoradiation therapy (CRT) is important. DWI is a very sensitive technique to detect nodes. The study aim was to test the hypothesis that the absence of nodes at DWI after CRT is concordant with a ypN0 status.

MATERIALS AND METHODS

A retrospective study was performed of 90 patients with rectal cancer treated with CRT followed by restaging MRI at 1.5 T, including DWI (highest b value, 1000 s/mm²). Two independent readers counted the number of nodes visible in the mesorectal compartment on DW images obtained after CRT. The number of nodes on DWI (0 vs ≥ 1) was compared with the number of metastatic nodes at histopathology or long-term clinical follow-up (yN0 vs yN-positive status).

RESULTS

Seventy-one patients had a yN0 status, and 19 had a yN-positive status. For 10 patients, no nodes were observed at DWI, which was concordant with a yN0 status in 100% of cases. In the other 61 patients with a yN0 status, the median number of nodes detected at DWI was three (range, 1-17 nodes). To differentiate between yN0 and yN-positive status, sensitivity was 100%, specificity was 14%, the positive predictive value was 24%, and the negative predictive value was 100%.

CONCLUSION

Although the absence of nodes at DWI is not a frequent finding, it appears to be a reliable predictor of yN0 status after CRT in patients with rectal cancer. DWI may thus be a helpful adjunct in assessing response after CRT and may help select patients for organ-saving treatment.

Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope

BACKGROUND AND AIM

Endoscopic ultrasound (EUS) is considered the most sensitive modality for local staging of esophageal cancer (ECA) and current guidelines recommend EUS in all patients with non-metastatic disease. Our aim was to identify a subset of patients with stenotic, non-metastatic ECA who will not benefit from staging EUS.

METHODS

This multicenter study evaluated consecutive patients with newly diagnosed non-metastatic ECA referred for local staging by EUS. All patients had endoscopic evaluation of malignant strictures with 9.8/9.9-mm diagnostic gastroscope prior to EUS. Main outcome measure was to evaluate the relationship between degree of malignant stenosis and tumor staging by EUS.

RESULTS

Of 100 patients (median age, 65 years; male 81%), gastroscope could not be advanced past the stricture in 46, all of whom (100%) had locally advanced disease at EUS: T3N0/N+ in 39 and T4N0/N+ in seven. Echoendoscope could not traverse the stricture in any of these patients. Gastroscope could be advanced through the stricture in 54 patients in whom EUS staging was T1N0 in five, T2N0/N+ in eight and T3N0/N+ in 41; echoendoscope could not pass through the stricture in 24 of these 54 (44.4%) patients, all of whom had T3N0/N+ disease. On logistic regression analysis, inability to pass a gastroscope through the stricture was significantly associated with advanced (T3/4) tumor stage (OR = 28.7, 95% CI = 1.64-501.2; P = 0.021).

CONCLUSION

Routine EUS examination may not be required in all patients with ECA as the inability to advance a diagnostic gastroscope past a malignant stricture correlates 100% with locally advanced disease on EUS.

Alternative staging of regional lymph nodes in gastric cancer

The TNM pN stage based on the number of metastatic lymph nodes is an independent prognostic factor in gastric cancer. Many studies have highlighted the phenomenon of stage migration and problems in comparing groups of patients with different numbers of total lymph nodes harvested within TNM staging. The current version of UICC/AJCC and JGCA TNM classifications postulates a minimal number of 16 lymph nodes as the base for N stage determination. Alternative systems such as lymph node ratio (LNR), positive to negative lymph node ratio (PNLNR), and LOGODDS (or LODDS), were implemented to increase the quality of LN assessment. These methods have reached the background in the literature, but to date no standard approach according to the cut-offs for the stages has been implemented. LOGODDS is the method that most reflects the number of harvested lymph nodes. The rationale for alternative staging methods, their correlations, and limitations are presented.

Pre-operative lymph node status of gastric cancer evaluated by multidetector computed tomography

The purpose of the present study was to perform a meta-analysis to evaluate the diagnostic value of Multidetector computed tomography (MDCT) in the pre-operative lymph node (N) staging in gastric cancer (GC) patients. The Medline, Embase and Web of Knowledge were searched for studies assessing the diagnostic value of MDCT in the pre-operative evaluation of TNM staging in GC patients. We pooled the sensitivity, specificity, positive and negative Likelihood ratio (LR+ and LR-), Diagnostic Odds Ratio (DOR) and constructed summary receiver operating characteristic curves (ROC). A total of 30 studies including 6637 GC patients were analyzed. The pooled estimates of sensitivity, specificity, LR+, LR- and DOR of MDCT in the detection of pre-operative N staging in GC patients were 0.67 (95% CI: 0.66-0.69 ), 0.84 (95% CI: 0.83-0.85), 3.25 (95% CI: 2.69-3.93), 0.36 (95% CI: 0.28-0.46) and 10.31 (95% CI: 7.66-13.88), respectively. The results of a summary ROC showed that the AUC and Q* were 0.8338 and 0.7661, respectively. As a control, the AUC and Q* of endoscopic ultrasonography were 0.8063 and 0.7414, respectively. Currently, it is necessary to recommend the routine clinical application of MDCT in the preoperative evaluation of lymph node status in GC patients.

Diagnostic value of dual time-point 18 F-FDG PET/CT versus single time-point imaging for detection of mediastinal nodal metastasis in non-small cell lung cancer patients: a meta-analysis

BACKGROUND

Lymph node staging in non-small cell lung cancer (NSCLC) is challenging and important for determining treatment policy. Conflicting results have been presented to date.

PURPOSE

To evaluate the diagnostic performance of dual time-point (DTP) 18 F-FDG PET/CT compared with single time-point (STP) imaging for detecting mediastinal nodal metastases in patients with NSCLC.

MATERIAL AND METHODS

The PubMed, EMBASE, EBSCO, and Web of Knowledge databases were searched for relevant articles. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated using Meta-Disc software. Summary receiver-operating characteristic (SROC) curves were also constructed. The potential for between-study heterogeneity was explored using subgroup analyses.

RESULTS

A total of eight studies involving 654 patients fulfilled the inclusion criteria. On a per-patient analysis, the pooled sensitivity and specificity with a 95% confidence interval (CI) for DTP PET/CT were 0.85 (0.78-0.91), 0.75 (0.68-0.82), and for STP imaging, they were 0.79 (0.70-0.85), 0.73 (0.65-0.79), respectively. On a per-lesion basis, the corresponding values for DTP imaging were 0.84 (0.81-0.86), 0.89 (0.87-0.91), and for STP imaging, they were 0.84 (0.80-0.86), 0.83 (0.81-0.85), respectively.

CONCLUSION

DTP PET/CT performed better than STP imaging in evaluating the lymph node status of NSCLC patients and had the potential to be broadly applied in clinical practice. However, due to the small sample size and large heterogeneity, current evidence does not justify the implementation of DTP imaging in routine PET protocols for mediastinal lymph node staging of NSCLC.

Lymph node staging in prostate cancer

Nodal staging is important in prostate cancer treatment. While surgical lymph node dissection is the classic method of determining whether lymph nodes harbor malignancy, this is a very invasive technique. Current noninvasive approaches to identifying malignant lymph nodes are limited. Conventional imaging methods rely on size and morphology of lymph nodes and have notoriously low sensitivity for detecting malignant nodes. New imaging techniques such as targeted positron emission tomography (PET) imaging and magnetic resonance lymphography (MRL) with iron oxide particles are promising for nodal staging of prostate cancer. In this review, the strengths and limitations of imaging techniques for lymph node staging of prostate cancer are discussed.

Number of negative lymph nodes should be considered for incorporation into staging for breast cancer

This study aimed to investigate the prognostic value of the number of involved lymph nodes (pN), number of removed lymph nodes (RLNs), lymph node ratio (LNR), number of negative lymph nodes (NLNs), and log odds of positive lymph nodes (LODDS) in breast cancer patients. The records of 2,515 breast cancer patients who received a mastectomy or breast-conserving surgery were retrospectively reviewed. The log-rank test was used to compare survival curves, and Cox regression analysis was performed to identify prognostic factors. The median follow-up time was 64.2 months, and the 8-year disease-free survival (DFS) and overall survival (OS) were 74.6% and 82.3%, respectively. Univariate analysis showed that pN stage, LNR, number of RLNs, and number of NLNs were significant prognostic factors for DFS and OS (all, P < 0.05). LODDS was a significant prognostic factor for OS (P = 0.021). Multivariate analysis indicated that pN stage and the number of NLNs were independent prognostic factors for DFS and OS. A higher number of NLNs was associated with higher DFS and OS, and a higher number of involved lymph nodes were associated with poorer DFS and OS. Patients with a NLNs count > 9 had better survival (P < 0.001). Subgroup analysis showed that the NLNs count had a prognostic value in patients with different pT stages and different lymph node status (log-rank P < 0.05). For breast cancer, pN stage and NLNs count have a better prognostic value compared to the RLNs count, LNR, and LODDS. Number of negative lymph nodes should be considered for incorporation into staging for breast cancer.

Staging lymph node metastases from lung cancer in the mediastinum

BACKGROUND

The presence of tumor metastases in the mediastinum is one of the most important elements in determining the optimal treatment strategy in patients with non-small cell lung cancer. This review is aimed at examining the current strategies for investigating lymph node metastases corresponding to an "N2" classification delineated by The International Staging Committee of the International Association for the Study of Lung Cancer (IASLC).

METHODS

Extensive review of the existing scientific literature related to the investigation of mediastinal lymph node metastases was undertaken in order to summarize and report current best practices.

CONCLUSIONS

N2 disease is very heterogeneous requiring multiple modalities for thorough investigation. New research is now focusing on better identifying, defining, and classifying lymph node metastases in the mediastinum. Molecular staging and sub-classifying mediastinal lymph node metastases are being actively researched in order to provide better prognostic value and to optimize treatment strategies. Non-invasive imaging, such as PET/CT and minimally invasive techniques such as endobronchial and endoscopic ultrasound guided biopsy, are now the lead investigative methods in evaluating the mediastinum for metastatic presence.

Implications of inadequate lymph node staging in resectable gastric cancer: a contemporary analysis using the National Cancer Data Base

BACKGROUND

National guidelines recommend examination of ≥ 15 lymph nodes for adequate staging of resectable gastric adenocarcinoma (GA). The relevance of these guidelines, which were established before the increasing use of multimodality therapy, and the impact of inadequate lymph node staging (LNS) in a contemporary cohort have not been extensively explored.

METHODS

Stage I-III GA patients who underwent gastrectomy from 1998 to 2011 were identified using the National Cancer Data Base. Trends in LNS adequacy, predictors of inadequate LNS (< 15 LN examined) and the relationship between LNS and overall survival (OS) were analyzed.

RESULTS

In 22,409 patients, compliance with LNS guidelines was poor (inadequate LNS in 61.2% of cases, median LN harvested in 11.0%). Subtotal/partial gastrectomy was the strongest predictor of inadequate LNS (OR = 2.01, P < .001). Survival analyses included 9139 patients with minimum 5 years follow-up; median, 1-year, and 5-year survival was 35.6 months, 75.5%, and 39.7%, respectively. LN positivity (HR = 1.90) and age > 76 years (HR = 1.73) were the strongest predictors of worse OS (both P < .001). Inadequate LNS was independently associated with worse OS (HR = 1.33, P < .001). Median OS after inadequate compared to adequate LNS was significantly worse (33.3 months versus 42.0 months, P < .001), regardless of AJCC clinical stage subgroup or tumor T classification (both P < .001).

CONCLUSIONS

Adequate LNS is achieved in a minority of patients. Inadequate LNS was independently associated with worse OS. Examination of ≥ 15 LN is a reproducible prognosticator of gastric cancer outcomes in the United States and should continue to serve as a benchmark for quality of care.

Current oncologic concepts and emerging techniques for imaging of head and neck squamous cell cancer

The incidence of head and neck squamous cell carcinoma (HNSCC) is increasing and currently they account for 5% of all malignancies worldwide. Inspite of ongoing developments in diagnostic imaging and new therapeutic options, HNSCC still represents a multidisciplinary challenge.One of the most important prognostic factors in HNSCC is the presence of lymph node metastases. Patients with confirmed nodal involvement have a considerable reduction of their 5-year overall survival rate. In the era of individually optimised surgery, chemotherapy and intensity modulated radiotherapy, the main role of pre- and posttherapeutic imaging remains cancer detection at an early stage and accurate follow-up. The combined effort of early diagnosis and close patient monitoring after surgery and/or radio-chemotherapy influences disease progression and outcome predicition in patients with HNSCC.This review article focuses on currrent oncologic concepts and emerging tools in imaging of head and neck squamous cell cancer. Besides the diagnostic spectrum of the individual imaging modalities, their limitations are also discussed. One main part of this article is dedicated to PET-CT which combines functional and morphological imaging. Furthermore latest developments in MRI are presented with regard to lymph node staging and response prediction. Last but not least, a clinical contribution in this review explains, which information the head and neck surgeon requires from the multimodality imaging and its impact on operation planning.

A logistic regression model for predicting axillary lymph node metastases in early breast carcinoma patients

Nodal staging in breast cancer is a key predictor of prognosis. This paper presents the results of potential clinicopathological predictors of axillary lymph node involvement and develops an efficient prediction model to assist in predicting axillary lymph node metastases. Seventy patients with primary early breast cancer who underwent axillary dissection were evaluated. Univariate and multivariate logistic regression were performed to evaluate the association between clinicopathological factors and lymph node metastatic status. A logistic regression predictive model was built from 50 randomly selected patients; the model was also applied to the remaining 20 patients to assess its validity. Univariate analysis showed a significant relationship between lymph node involvement and absence of nm-23 (p = 0.010) and Kiss-1 (p = 0.001) expression. Absence of Kiss-1 remained significantly associated with positive axillary node status in the multivariate analysis (p = 0.018). Seven clinicopathological factors were involved in the multivariate logistic regression model: menopausal status, tumor size, ER, PR, HER2, nm-23 and Kiss-1. The model was accurate and discriminating, with an area under the receiver operating characteristic curve of 0.702 when applied to the validation group. Moreover, there is a need discover more specific candidate proteins and molecular biology tools to select more variables which should improve predictive accuracy.

Near infrared fluorescent optical imaging for nodal staging

Current techniques to assess lymph node metastases in cancer patients include lymphoscintigraphy after administration of a nonspecific radiocolloid in order to locate and resect lymph nodes for pathological examination of harbored cancer cells. Clinical trials involving intradermal or subcutaneous injection of antibody-based nuclear imaging agents have demonstrated the feasibility for target-specific, molecular imaging of cancer-positive lymph nodes. The basis for employing near-infrared (NIR) optical imaging for assessing disease is evidenced by recent work showing functional lymph imaging in mice, swine, and humans. We review antibody-based immunolymphoscintigraphy with an emphasis on the use of trastuzumab (or Herceptin) to target human epidermal growth factor receptor-2 (HER2) overexpressed in some breast cancers. Specifically, we review in vitro and preclinical imaging data from our laboratory that show how the dual-labeled agent ((111)In-DTPA)(n)-trastuzumab-(IRDye800)(m) utilizes the high photon count provided by an NIR fluorescent dye, IRDye 800CW, and the radioactive signal from a gamma emitter, Indium-111, for possible detection of HER2 metastasis in lymph nodes. We show that the accumulation and clearance of ((111)In-DTPA)(n)-trastuzumab-(IRDye800)(m) from the axillary nodes of mice occurs 48 h after intradermal injection into the dorsal aspect of the foot. The requirement for long clearance times from normal, cancer-negative nodes presents challenges for nuclear imaging agents with limited half-lives but does not hamper NIR optical imaging.