Comparable Accuracy of Quantitative and Visual Analyses of [18F]FDG PET/CT for the Detection of Lymph Node Metastases from Head and Neck Squamous Cell Carcinoma

BACKGROUND

In head and neck squamous cell carcinoma (HNSCC), [18F]FDG PET/CT is recommended for detecting recurrent disease and in the initial staging for evaluating distant metastases, but its use in detecting cervical lymph metastases remains unclear. The aim of this study is to evaluate and compare the diagnostic accuracy of [8F]FDG-PET/CT using visual and semi-quantitative analyses for detecting the nodal involvement in HNSCC.

METHODS

We analyzed consecutive patients who underwent a preoperative [18F]FDG-PET/CT and neck dissection for HNSCC at our tertiary hospital. A blinded evaluation of the [18F]FDG uptake in each neck level was performed using a semi-quantitative approach (SUVmax and SUVR) and a visual grading system (uptake superior to the internal jugular vein for grade 1 and superior to the liver for grade 2). Analyses were compared to the histological results.

RESULTS

In our 211 patients, analyses demonstrated similar diagnostic accuracy using a semi-quantitative approach or a visual grading system. Regarding the visual grading system, [18F]FDG-PET/CT detected nodal metastases with a specificity of 83% for lymph nodes classified as grade 1 and 98% for those classified as grade 2. The sensitivity was moderate, ranging from 60 to 63%.

CONCLUSIONS

[18F]FDG PET/CT has a high specificity for detecting lymph node metastases in HNSCC and therefore must be considered in the nodal clinical staging.

Sentinel Lymph Node Biopsy in Prostate Cancer: An Overview of Diagnostic Performance, Oncological Outcomes, Safety, and Feasibility

Sentinel node biopsy (SNB) for prostate cancer (PCa) represents an innovative technique aimed at improving nodal staging accuracy. The routinary adoption of this procedure in patients undergoing radical prostatectomy (RP) might be crucial to identify candidates who could effectively benefit from extensive pelvic lymph nodal dissection (ePLND). Despite some promising results, SNB for PCa is still considered experimental due to the lack of solid evidence and procedural standardization. In this regard, our narrative review aimed to analyze the most recent literature in this field, providing an overview of both the diagnostic accuracy measures and the oncological outcomes of SNB.

Accuracy of nodal staging by 18F-FDG-PET/CT in limited disease small-cell lung cancer

BACKGROUND

Small-cell lung cancer (SCLC) is highly aggressive with a nearly incurable disease in most cases. The most important prognostic factor is the status of the mediastinal lymph nodes. Only a small proportion of patients can be diagnosed at early stages and directed to curative multimodal treatment. Therefore, accuracy of nodal staging by (18F)-Fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) computed tomography (18F-FDG-PET/CT) in (very) limited disease SCLC, although not well investigated, is highly important.

METHODS

Treatment naive, non-bulky patients treated or diagnosed with SCLC between June 2012 and April 2020 with complete data including FDG-PET/CT and invasive mediastinal staging were retrospectively analyzed (n = 19). Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy of mediastinal lymph node staging of 18F-FDG-PET/CT was calculated.

RESULTS

The FDG-PET/CT showed a sensitivity of 91%, and the specificity was calculated as 87.5%. In this cohort, the disease prevalence in lymph nodes was 58% (n = 11). Positive predictive value was 91%, NPV 88% and accuracy calculated at 89%. One patient was upstaged from single-level N2 to multilevel N2. In one patient, upstaging in invasive staging was performed from N2 to N3, and one patient was downstaged from N1 to N0.

CONCLUSIONS

FDG-PET/CT is a valuable tool for the detection of distant metastases, but in mediastinal staging of SCLC some limitations might remain. Invasive methods remain the gold standard. Therefore, the mediastinal lymph nodal status of patients with SCLC screened for multimodal treatment should be further evaluated by additional invasive techniques to verify the exact N-staging and to optimize treatment stratification.

Multidisciplinary Postoperative Validation of (18)F-FDG PET/CT Scan in Nodal Staging of Resected Non-Small Cell Lung Cancer

BACKGROUND

The aim of this study was to examine the validity of PET/CT scans in the preoperative identification of lymph node metastases (LNM) and compare them with postoperative outcomes.

METHODS

In this retrospective study, we included 87 patients with a solitary lung nodule or biopsy-proven non-small cell lung cancer treated in our institution from 2009 to 2015. Patients were divided into two groups and four subgroups, depending on pre- and postoperative findings.

RESULTS

According to our analysis, PET/CT scan has a sensitivity of 50%, a specificity of 88.89%, a positive predictive value of 63.16%, and a negative predictive value of 82.35%. Among the patients, 13.8% were downstaged in PET-CT, while 8% were upstaged. In 78.2% of cases, the PET/CT evaluation was consistent with the histology. Metastases without extracapsular invasion were seldom recognized on PET/CT.

CONCLUSIONS

This analysis showed the significance of extracapsular tumor invasion, which causes an inflammatory reaction, on LNM, which is probably responsible for preoperative false-positive findings. In conclusion, PET/CT scans are very effective in identifying patients without tumors. Furthermore, it is highly probable that patients with negative findings are free of disease.

Lymph Nodes Evaluation in Rectal Cancer: Where Do We Stand and Future Perspective

The assessment of nodal involvement in patients with rectal cancer (RC) is fundamental in disease management. Magnetic Resonance Imaging (MRI) is routinely used for local and nodal staging of RC by using morphological criteria. The actual dimensional and morphological criteria for nodal assessment present several limitations in terms of sensitivity and specificity. For these reasons, several different techniques, such as Diffusion Weighted Imaging (DWI), Intravoxel Incoherent Motion (IVIM), Diffusion Kurtosis Imaging (DKI), and Dynamic Contrast Enhancement (DCE) in MRI have been introduced but still not fully validated. Positron Emission Tomography (PET)/CT plays a pivotal role in the assessment of LNs; more recently PET/MRI has been introduced. The advantages and limitations of these imaging modalities will be provided in this narrative review. The second part of the review includes experimental techniques, such as iron-oxide particles (SPIO), and dual-energy CT (DECT). Radiomics analysis is an active field of research, and the evidence about LNs in RC will be discussed. The review also discusses the different recommendations between the European and North American guidelines for the evaluation of LNs in RC, from anatomical considerations to structured reporting.

Does Angiosarcoma of the Breast Need Nodal Staging?

BACKGROUND

Breast angiosarcoma is a rare malignancy classically associated with hematogenous metastases. We sought to determine the prevalence of pathologic nodal involvement in patients with nonmetastatic, resected breast angiosarcoma and its association with overall survival.

STUDY DESIGN

The National Cancer Database was used to identify patients with nonmetastatic angiosarcoma of the breast who underwent surgical resection from 2004 to 2017. The prevalence of regional lymph node operation and nodal positivity was calculated. The Kaplan-Meier method was used to evaluate overall survival among node-positive and node-negative patients. Cox proportional hazard modeling was used to evaluate the adjusted association of nodal positivity with overall survival.

RESULTS

We included 991 patients with angiosarcoma. The median age was 69 years (interquartile range 57 to 78), and the cohort was 99% female. A total of 298 patients (30%) had pathologic regional nodal evaluation. Of those, 15 (5.0%) had positive regional lymph nodes. Node-positive patients had significantly worse survival than patients with negative regional lymph nodes. After adjusting for patient, tumor, and treatment factors, a positive regional lymph node was associated with worse overall survival compared with patients with no nodal evaluation (hazard ratio 3.20; 95% CI 1.75 to 5.86; p < 0.001).

CONCLUSIONS

Patients with nonmetastatic angiosarcoma of the breast have a 5% regional lymph node positivity rate, which is at a common threshold to consider evaluation, and identifies patients with poor survival. A prospective study to determine performance characteristics of sentinel lymph node biopsy is warranted.

Development and Validation of an Improved Pathological Nodal Staging System in Men With Prostate Cancer

BACKGROUND

Prostate cancer pathological nodal staging uses a single category for all node-positive patients. We sought to improve risk stratification by creating and validating a novel pathological nodal staging system incorporating number of metastatic lymph nodes (+LNs).

METHODS

118,450 men who underwent radical prostatectomy (RP) for nonmetastatic prostate cancer in the National Cancer Database comprised our development cohort. Multivariable Cox proportional hazards analysis with restricted cubic splines was used to assess the non-linear association between number of +LNs and overall mortality (OM). A novel staging system based on number of +LNs was derived by recursive partitioning analysis (RPA). The staging system was validated for prediction of overall and prostate-specific mortality (PCSM) in 105,568 men with nonmetastatic prostate cancer undergoing RP from the Surveillance, Epidemiology, and End Results database. Discrimination was assessed via Harrell's c-index.

RESULTS

In multivariable Cox analysis, OM risk increased with higher number of +LNs up to four (HR1.30 per each LN+, 95%CI 1.23-1.38), with a non-statistically significant increase in risk (HR 1.05, 95%CI 0.99-1.11) beyond four +LN. In the development cohort, RPA identified optimal cutoffs at 0 (N0:Ref), 1 (N1:HR1.40, 95%CI 1.25-1.58), 2 (N2:HR1.67, 95%CI 1.40-1.99), 3-5 (N3a: HR2.18, 95%CI 0.84-2.60), and ≥6 (N3b:HR3.00, 95%CI 2.37-3.79) +LNs. In the validation cohort, these groups had markedly different 10-year OM (0+LNs (N0:15%), 1+LN (N1:35%), 2+LNs (N2:43%), 3-5+LNs (N3a:52%), and ≥6+LNs(N3b:59%) (p <0.05)) and PCSM. The novel staging system improved survival classification over current staging for node-positive patients (optimism-corrected c-index 0.669 (95%CI 0.668-0.671) vs 0.649 (95%CI 0.648-0.651)).

CONCLUSIONS

Pathological nodal staging in prostate cancer is improved with stratification by number of +LNs.

Application of Artificial Neural Network to Preoperative 18F-FDG PET/CT for Predicting Pathological Nodal Involvement in Non-small-cell Lung Cancer Patients

Purpose: To evaluate the performance of artificial neural networks (aNN) applied to preoperative ¹⁸F-FDG PET/CT for predicting nodal involvement in non-small-cell lung cancer (NSCLC) patients.

Methods: We retrospectively analyzed data from 540 clinically resectable NSCLC patients (333 M; 67.4 ± 9 years) undergone preoperative ¹⁸F-FDG PET/CT and pulmonary resection with hilo-mediastinal lymphadenectomy. A 3-layers NN model was applied (dataset randomly splitted into 2/3 training and 1/3 testing). Using histopathological reference standard, NN performance for nodal involvement (N0/N+ patient) was calculated by ROC analysis in terms of: area under the curve (AUC), accuracy (ACC), sensitivity (SE), specificity (SP), positive and negative predictive values (PPV, NPV). Diagnostic performance of PET visual analysis (N+ patient: at least one node with uptake ≥ mediastinal blood-pool) and of logistic regression (LR) was evaluated.

Results: Histology proved 108/540 (20%) nodal-metastatic patients. Among all collected data, relevant features selected as input parameters were: patients' age, tumor parameters (size, PET visual and semiquantitative features, histotype, grading), PET visual nodal result (patient-based, as N0/N+ and N0/N1/N2). Training and testing NN performance (AUC = 0.849, 0.769): ACC = 80 and 77%; SE = 72 and 58%; SP = 81 and 81%; PPV = 50 and 44%; NPV = 92 and 89%, respectively. Visual PET performance: ACC = 82%, SE = 32%, SP = 94%; PPV = 57%, NPV = 85%. Training and testing LR performance (AUC = 0.795, 0.763): ACC = 75 and 77%; SE = 68 and 55%; SP = 77 and 82%; PPV = 43 and 43%; NPV = 90 and 88%, respectively.

Conclusions: aNN application to preoperative ¹⁸F-FDG PET/CT provides overall good performance for predicting nodal involvement in NSCLC patients candidate to surgery, especially for ruling out nodal metastases, being NPV the best diagnostic result; a high NPV was also reached by PET qualitative assessment. Moreover, in such population with low a priori nodal involvement probability, aNN better identify the relatively few and unexpected nodal-metastatic patients than PET analysis, so supporting the additional aNN use in case of PET-negative images.

Novel Diagnostic Approaches for Assessment of the Clinically Negative Neck in Head and Neck Cancer Patients

In head and neck cancer, the presence of nodal disease is a strong determinant of prognosis and treatment. Despite the use of modern multimodality diagnostic imaging, the prevalence of occult nodal metastases is relatively high. This is why in clinically node negative head and neck cancer the lymphatics are treated “electively” to eradicate subclinical tumor deposits. As a consequence, many true node negative patients undergo surgery or irradiation of the neck and suffer from the associated and unnecessary early and long-term morbidity. Safely tailoring head and neck cancer treatment to individual patients requires a more accurate pre-treatment assessment of nodal status. In this review, we discuss the potential of several innovative diagnostic approaches to guide customized management of the clinically negative neck in head and neck cancer patients.

The impact of pathologic staging of the hilar/mediastinal nodes on outcomes in patients with early-stage NSCLC receiving stereotactic body radiotherapy

Background

The importance of invasive mediastinal nodal staging in early-stage non-small cell lung cancer (NSCLC) in the PET/CT era is dependent on tumor factors that increase risk of nodal metastasis. At our institution, patients undergo biopsy via either CT-guidance (without nodal staging) or navigational bronchoscopy with endobronchial ultrasound transbronchial needle aspiration for nodal staging. This study aims to compare outcomes after stereotactic body radiotherapy (SBRT) stratified by receipt of invasive mediastinal nodal staging.

Methods

In this retrospective study, records of all consecutive patients undergoing SBRT for early-stage NSCLC between 2010 and 2017 were analyzed. The association between time-to event outcomes (recurrence and survival) were evaluated with covariates of interest including tumor size, location, histology, smoking history, prior lung cancer history, radiation dose and receipt of nodal staging. Both univariable and multivariable analyses were used to examine these comparisons.

Results

Overall, 158 patients were treated with SBRT. One hundred forty-nine out of one hundred fifty-eight patients (94%) underwent PET/CT staging, and all patients underwent tumor-directed biopsy. Seventy-nine patients underwent navigational bronchoscopy with nodal staging and 79 patients underwent CT-guided biopsy without nodal staging. Receipt of nodal staging was not associated with tumor size (P=0.35), yet was associated with central tumor location (P<0.001). There was no statistically significant association between receipt of nodal staging and time-to-event recurrence or survival outcomes; for example 3-year overall survival (OS) was 65% vs. 67% (P=0.65) and 3-year freedom from nodal failure was 84% vs. 69% (P=0.1) for those with and without nodal staging, respectively.

Conclusions

Similar recurrence and survival outcomes were observed after SBRT regardless of receipt of invasive mediastinal nodal staging. Further prospective evaluation can help identify which patients might derive greatest benefit from invasive staging of the mediastinum in the PET/CT era.

A large real-world cohort study of examined lymph node standards for adequate nodal staging in early non-small cell lung cancer

Background

The current National Comprehensive Cancer Network (NCCN) guidelines for non-small cell lung cancer (NSCLC) recommend that surgeons sample is not clear. We aimed to define a minimal number of examined lymph nodes for removal or sampling for optimized nodal staging recommendation, with a focus on T_1–3N₀M₀ patients.

Methods

A total of 55,101 consecutive patients were selected, including 52,099 patients with US Surveillance, Epidemiology, and End Results (SEER) data and 3,002 patients in a Chinese multicenter database from 11 thoracic referral centers, who underwent complete resection plus lymph node dissection or sampling for stage T_1–3N₀M₀ NSCLC. Propensity score-matching analysis was performed with R software, and a cut-off value was calculated using X-tile software. Survival was evaluated using the Kaplan-Meier method and Cox proportional hazard models.

Results

Five-year survival rates with respect to total examined lymph nodes numbers (examined lymph nodes <10 vs. examined lymph nodes ≥10) were 69% and 64% (group A), 66% and 63% (group B), 62% and 58% (group C), 81% and 75% (group D). There were significant differences between examined lymph nodes <10 and examined lymph nodes >10 in each group (P<0.001).

Conclusions

A minimum of 10 examined lymph nodes would significantly improve T_1–3N₀M₀ NSCLC prognosis and patients’ survival rates if implemented as a minimum standard for lymphadenectomy. Therefore, we recommended a minimum of 10 examined lymph nodes for T_1–3N₀M₀ patients.

Prognostic value of lymph node ratio versus American Joint Committee on Cancer N classification for surgically resected human papillomavirus-associated oropharyngeal squamous cell carcinoma

BACKGROUND

We compared prognostic values of lymph node ratio (LNR) and AJCC 8 N classification in surgically resected human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Using the National Cancer Database, we identified patients with HPV-associated OPSCC from 2010 to 2016 who underwent definitive surgical resection. Patients were analyzed by nodal grouping (LNR, N stage) and adjuvant radiation therapy(RT). Primary endpoint was overall survival.

RESULTS

We identified 4166 patients. Survival analysis showed significant improvement for LNR≤6% versus >6% (5 year OS% 92.7% vs. 83.7%, p < 0.001). N classification demonstrated good prognostic ability (5 year OS% for pN0, pN1, pN2 were 91.3%, 90.1%, 78.8%, p < 0.001), but poor separation among stages (compared to pN0: pN1 HR 1.40 [95% CI 0.63, 3.09], p = 0.41; pN2 HR 2.50 [95% CI 1.08, 5.81], p = 0.033). RT improved survival in the LNR > 6% group (5 year OS% 85.4% vs. 74.9%, p < 0.001; HR 0.41 [95% CI 0.28, 0.58], p < 0.001).

CONCLUSIONS

LNR should be considered an adjunct category in future staging systems for HPV-associated OPSCC.

Molecular Nodal Restaging Based on CEACAM5, FGFR2b and PTPN11 Expression Adds No Relevant Clinical Information in Resected Non-Small Cell Lung Cancer

BACKGROUND

The relapse rate in non-small cell lung cancer (NSCLC) is high, even in localized disease, suggesting that the current approach to pathological staging is insufficiently sensitive to detect occult micrometastases present in resected lymph nodes. Therefore, we aimed to determine the prognostic value of the expression of embryonic molecular markers in histologically-negative lymph nodes of completely-resected NSCLC.

METHODS

76 completely-resected NSCLC patients were included: 60 pN0 and 16 pN1. Primary tumors and 347 lymph node were studied. CEACAM5, FGFR2b, and PTPN11 expression levels were evaluated through mRNA analysis using real-time RT-qPCR assay. Statistical analyses included the Kruskal-Wallis test, Kaplan Meier curves, and log-rank tests.

RESULTS

CEACAM5 expression levels were scored as high in of 90 lymph nodes (26%). The molecular-positive lymph nodes lead to the restaging of 37 (62%) pN0 patients as molecular N1 or N2 and 5 (31%) pN1 cases were reclassified as molecular-positive N2. Surprisingly, molecular-positive patients associated with a better OS (overall survival, p = 0,04). FGFR2b overexpression was observed in 41 (12%) lymph nodes leading to the restaging of 17 patients (22%). Again a trend was observed toward a better DFS (disease-free survival) in the restaged patients (p = 0,09). Accordingly, high expression levels of CEACAM5 or FGFR2b in the primary were related to better DFS (p = 0,06; p < 0,02, respectively).

CONCLUSION

Molecular nodal restaging based on expression levels of CEACAM5 and/or FGFR2b, does not add relevant clinical information to pathological staging of NSCLC likely related to the better prognosis of their overexpression in primary tumors.

Prognostic Impact of Tumor Status, Nodal Status and Tumor Sidedness in Metastatic Colon Cancer

Background Locally advanced primary tumors have been associated with poor overall survival (OS) in non-metastatic colon cancer. However, their impact on metastatic colon cancer (mCC) is not fully defined. The association between primary tumor location and prognosis in mCC is also evolving. Methods Using National Cancer Data Base, we identified a cohort of 25,377 patients diagnosed with mCC from 2004-2009. Chi-square test was used for descriptive analyses, while all potential prognostic factors were evaluated using Kaplan-Meier survival estimates and Cox proportional hazards regression modeling. Results The five-year OS for the entire study cohort was 12.3%. Factors associated with significant survival impact in multivariate analysis included age, gender, race, comorbidity index, academic level of treating institution, insurance status, income, year of diagnosis, primary tumor site, histologic differentiation, pathologic tumor stage (pT), pathologic nodal stage (pN), and modality of chemotherapy. pT1 lesions demonstrated poor prognosis in stage IV colon cancers, not statistically different when compared to survival outcomes observed in cases with pT4 lesions. Regional nodal involvement demonstrated poor OS in full cohort analysis and subgroup analysis independent of primary tumor location. Both right-sided and transverse colon tumors had similarly worse OS compared to left-sided tumors (right-sided: HR: 1.21, 95% CI: 1.17-1.25; transverse: HR: 1.21, 95% CI: 1.15-1.27). Conclusions T1 lesions arising from right-side or transverse colon portend a poor prognosis in mCC, while regional lymph node involvement by itself is an independent poor prognostic factor. Right-sided tumors are associated with poor outcomes than left-sided tumors, suggesting the role of underlying molecular or biologic variants.

Alternative methods of lymph node staging in lung cancer: a narrative review

The nodal status indicator in non-small cell lung cancer is one of the most crucial prognostic factors available. However, there are still many arguments among scientists regarding whether the currently used nodal status descriptor should be changed in the forthcoming editions of the Tumor Node Metastasis classification or whether it is precise enough and should be maintained as is. We reviewed studies concerning nodal factor classifications to evaluate their accuracy in non-small cell lung cancer patients and to address the previously mentioned challenge. We reviewed the PubMed database regarding the following classifications: ongoing 8^th edition of the Tumor Node Metastasis classification, number of positive lymph nodes, number of negative lymph nodes, number of dissected lymph nodes, lymph node ratio, nodal chains, log odds of positive lymph nodes, zone-based classification and one that is based on the number of lymph node stations involved. Moreover, we analysed data regarding various combinations of these classifications. Our analysis showed that the present nodal staging may not accurately categorize every lung cancer patient. The number of positive lymph nodes and lymph node ratio or the log odds of positive lymph nodes (as the mathematical modification of lymph node ratio) are more legitimate, as they possess very robust data and should be considered initially as additional factors that can be incorporated in ongoing nodal staging systems. Forthcoming non-small cell lung cancer staging systems could benefit from the addition of quantitative-based parameters. Additionally, the minimal extent of lymphadenectomy should be established as staging benefits from it. International, prospective validation studies need to be performed to optimize the cut-off values and prognostic groups and to confirm the superiority of the newly suggested descriptors in non-small cell lung cancer nodal staging.

Diagnostic performance of PET/computed tomography versus PET/MRI and diffusion-weighted imaging in the N- and M-staging of breast cancer patients

OBJECTIVE

To provide a systematic review regarding the diagnostic performance of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) and diffusion-weighted imaging (DWI) compared to 18F-FDG PET/computed tomography (CT) focused on nodal and distant staging in breast cancer patients.

METHODS

The PubMed and Embase databases were searched for relevant publications until April 2020. Two independent reviewers searched for eligible articles based on predefined in- and exclusion criteria, assessed quality and extracted data.

RESULTS

Eleven eligible studies were selected from 561 publications identified by the search. In seven studies, PET/CT was compared with PET/MRI, and in five, PET/CT with DWI. Significantly higher sensitivity for PET/MRI compared to PET/CT in a lesion-based analysis was reported for all lesions together (77% versus 89%) in one study, osseous metastases (69-99% versus 92-98%) in two studies and hepatic metastases (70-75% versus 80-100%) in one study. Moreover, PET/MRI revealed a significantly higher amount of osseous metastases (90 versus 141) than PET/CT. PET/CT is associated with a statistically higher specificity than PET/MRI in the lesion detection of all lesions together (98% versus 96%) and of osseous metastases (100% versus 95%), both in one study. None of the reviewed studies reported significant differences between PET/CT and DWI for any of the evaluated sites. There is a trend toward higher specificity for PET/CT.

CONCLUSION

In general, there is a trend toward higher sensitivity and lower specificity of PET/MRI when compared to PET/CT. Results on the diagnostic performance of DWI are conflicting. Rather than evaluating it separate, it seems to have complementary value when combined with other MR sequences.

Systemic Sentinel Lymph Node Detection Using Fluorescence Imaging After Indocyanine Green Intravenous Injection in Colorectal Cancer: Protocol for a Feasibility Study

Background

Nodal staging is a major concern in colorectal cancer as it is an important prognostic factor. Several techniques that could potentially improve patient treatment and prognosis have been developed to increase the accuracy of nodal staging. Sentinel lymph node detection has been shown to accurately reflect nodal status in various tumors and has become the standard procedure in nodal staging of breast cancer and melanoma. However, in colorectal cancer, sentinel lymph node detection techniques are still controversial as the sensitivity reported in the literature varies from one study to another. Recently, indocyanine green fluorescence–guided surgery has been reported to be a useful technique for detection of macroscopic and microscopic metastatic deposits in lymph nodes after intravenous administration of indocyanine green dye. However, no studies have focused on the potential role of sentinel lymph node detection after systemic administration of indocyanine green dye, so-called systemic sentinel lymph nodes, or on the correspondence between the identification of the sentinel lymph node by standard local injection techniques and the detection of fluorescent lymph nodes with this new approach.

Objective

The aim of this protocol is to validate the concept of sentinel lymph nodes identified by fluorescence imaging after intravenous injection of indocyanine green dye and to compare the sentinel lymph nodes identified by fluorescence imaging with sentinel lymph nodes detected by the standard blue dye technique.

Methods

This study (SeLyNoFI; Sentinel Lymph Nodes Fluorescence Imaging) is a diagnostic, single-arm, open-label feasibility study, including patients with colorectal adenocarcinoma with or without metastatic disease who are admitted for elective colorectal resection of the primary tumor. This study evaluates the feasibility of a new approach for improving the accuracy of nodal staging using fluorescence imaging after intravenous administration of indocyanine green dye. Sensitivity, positive predictive value, and accuracy of the classical blue dye technique and of the investigatory fluorescence imaging technique will be calculated. Translational research will be proposed, if applicable.

Results

As of June 2020, this study has been registered. Submission for ethical review is planned for September 2020.

Conclusions

The potential correlation between the two different approaches to detect sentinel lymph nodes offers new strategies for improving the accuracy of nodal staging in colorectal cancer. This new concept of the systemic sentinel lymph node and a greater understanding of the interactions between systemic sentinel lymph nodes and standard sentinel lymph nodes may provide important information regarding the underlying mechanism of primary tumor lymphatic drainage. The enhanced permeability and retention effect can also play a role in the fluorescence of systemic sentinel lymph nodes, especially if these lymph nodes are inflamed. In this case, we can even imagine that this new technique will highlight more instances of lymph node–positive colorectal cancer.

International Registered Report Identifier (IRRID)

PRR1-10.2196/17976

Prognostic value of tumor deposits in rectal cancer: A monocentric series of 505 patients

BACKGROUND AND OBJECTIVES

It has been suggested that tumor deposits (TDs) may have a worse prognosis in rectal cancer compared with colonic cancer. The aim of this study was to assess TDs prognosis in rectal cancer.

METHODS

Patients who underwent total mesorectum excision for rectal adenocarcinoma (2011-2016) were included. A case-matched analysis was performed to assess the accurate impact of TDs for each pN category after exclusion of synchronous metastasis.

RESULTS

A total of 505 patients were included. TDs were observed in 99 (19.6%) patients, (pN1c = 37 [7.3%]). TDs were associated with pT3-T4 stage (P = .037), synchronous metastasis (P = .003), lymph node (LN) invasion (P = .041), vascular invasion (P = .001), and perineural invasion (P < .001). TD was associated with a worse 3-year disease-free survival (DFS) among pN0 (51.2% vs 79.8%; P < .001); pN1 patients (35.2% vs 70.1%; P = .004) but not among pN2 patients (37.5% vs 44.7%; P = .499). After matching, pN1c patients had a worse 3-year DFS compared with pN0 patients (58.6% vs 82.4%; P = .035) and a tendency toward a worse DFS among N1 patients (40.1% vs 64.2%; P = .153). DFS was worse when one TD was compared with one invaded LN (40.8% vs 81.3%; P < .001).

CONCLUSION

In rectal cancer, TDs have a metastatic risk comparable to a pN2 stage which may lead to changes in adjuvant treatment.

Evaluation of the Usefulness of FDG-PET/CT for Nodal Staging of Breast Cancer

BACKGROUND/AIM

Positron emission tomography/computed tomography (PET/CT) with ¹⁸F-fluorodeoxyglucose (18F-FDG) has recently been used to investigate lymph node (LN) metastases and several predictive features in patients with breast cancer (BC). The aim of this study was to assess the value of this non-invasive imaging procedure for axillary staging.

PATIENTS AND METHODS

Fifty patients with early primary unilateral, locally advanced, or recurrent invasive operable BC were enrolled. All patients underwent preoperative 18F-FDG PET/CT, and the results were compared with the histopathology of dissected axillary LNs and their biological and immunohistochemical characteristics. The diagnostic performance of 18F-FDG PET/CT in detecting LN metastases from primary or recurrent BC was analyzed. The mean values of the initial PET/CT parameters, including the primary tumour (SUV T) and ipsilateral axillary LNs (SUV LN), were compared with the clinicopathological features of patients to determine their usefulness for predicting clinical interactions.

RESULTS

The sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of 18F-FDG PET/CT for axillary LN staging were 87%, 90%, 88%, 93%, and 82%, respectively. Bivariate analyses showed strong interactions of nuclear grade (p=0.05), progesterone receptor expression (p=0.001), Ki-67 index (0.027), and local relapse with the SUV T. A high SUV LN value was significantly correlated with a higher nuclear grade score (p=0.05), oestrogen receptor negativity (p=0.001), progesterone receptor negativity (p=0.014), a high Ki-67 index (>20%; p=0.048), LN metastasis (p<0.001), a basal tumour (p=0.04), and locoregional recurrence (p<0.001).

CONCLUSION

PET/CT is a reproducible, non-invasive imaging modality that is useful for evaluating a primary BC mass and its relationship with metastatic axillary LNs, thereby predicting tumour behaviour and guiding clinical practice.

A pictorial review of bladder cancer nodal metastases

Lymph node involvement in bladder cancer is common and has prognostic implications. Early and accurate identification of metastatic lymph nodes is, therefore, important in ensuring appropriate patient triage and management. The purpose of this review is to provide a pictorial and educational overview of the staging and imaging appearance of metastatic lymph nodes in bladder cancer. Additionally, a secondary aim of this manuscript is to provide a review of the diagnostic accuracy of common imaging modalities available for detecting metastatic lymph nodes in affected patients.

Nodal staging of high-risk cutaneous squamous cell carcinoma

BACKGROUND

While progress has been made in defining the clinical and histopathologic features of high-risk cutaneous squamous cell carcinoma (HRcSCC), optimal staging guidelines remain elusive.

OBJECTIVE

We seek to guide clinical practice regarding nodal staging options for patients with HRcSCC via review of evolving definitions of HRcSCC, nodal staging options, and how nodal staging may impact treatment and affect outcomes.

METHODS

This was a retrospective review of the published peer-reviewed literature regarding risk stratification, nodal staging, and treatment and outcomes for patients with HRcSCC via PubMed.

RESULTS

For patients without clinical lymphadenopathy, based on literature from head and neck SCC, preoperative nodal staging with ultrasonography may be more useful than computed tomography or magnetic resonance imaging. Early nodal disease is usually curable, and therefore obtaining a sentinel lymph node biopsy specimen may be considered in those with negative imaging while we await studies of nodal staging outcomes.

LIMITATIONS

More data are needed to validate the relationships between primary tumor stage and sentinel lymph node biopsy status and to determine if early detection of nodal disease impacts survival for patients with HRcSCC.

CONCLUSION

It is reasonable to consider nodal staging for patients with HRcSCC (Brigham and Women's Hospital stage T2b and T3) in the absence of clinically palpable lymphadenopathy via radiographic imaging and, if negative, sentinel lymph node biopsy.

Predictors of unexpected nodal upstaging in patients with cT1-3N0 non-small cell lung cancer (NSCLC) submitted to thoracoscopic lobectomy

Background

In the last decades, the use of video-assisted thoracoscopic surgery (VATS) lobectomy for the treatment of early stage non-small cell lung cancer is continuously growing. This is mainly due to the development of more advanced surgical devices, to the rising incidence of peripheral lung tumors and is also favored by the increased reliability of preoperative staging techniques. Despite this progress, postoperative unexpected nodal upstaging is still a relevant issue. Aim of this study is to identify possible predictors of unexpected nodal upstaging in patients affected by cT1-3N0 NSCLC submitted to VATS lobectomy.

Methods

A total of 231 cases of cT1-3N0 patients submitted to thoracoscopic lobectomy at our centre between June 2012 and October 2016 were retrospectively reviewed. All data regarding clinical staging by means of computed tomography (CT) and positron-emission tomography (PET)/CT were collected and reviewed. The subsequent pathological staging has been analyzed, with special regards to the possible type of nodal involvement, and the number of pathological nodal stations.

Results

Most of the patients included in this study were in a clinical stage cT1aN0, cT1bN0 (stage IA) and cT2aN0 (stage IB), 86 (37.2%) patients, 73 (31.6%) patients and 62 (26.8%) patients, respectively. Postoperative histopathological analysis showed that the most frequent tumor histotype was adenocarcinoma (192 patients, 83.1%). Thirty-eight (16.5%) patients had a nodal upstaging; among these, 17 (7.4%) patients had N2 disease (8 patients with isolated mediastinal nodal involvement, 9 patients with N1 + N2 disease) and 21 (9.1%) patients had an isolated hilar nodal involvement (N1). At bivariate analysis, the clinical T (cT)-parameter (P=0.023), the histotype (P=0.029) and the pathological T (pT)-parameter (P=0.003) were identified as statistically significant predictors of nodal upstaging. Concerning the type of nodal upstaging, the pT was found to be statistically significant (P=0.042). At bivariate analysis for the number of involved nodal stations, a statistical significance was highlighted for the parameters cT (P=0.030) and pT (P=0.027). With linear logistic regression, histology as well as pT reached statistical significance (P=0.0275 and P=0.0382, respectively). No correlation was found between nodal upstaging and the intensity of FDG uptake in the primary lung tumor or with the timing between PET and surgery.

Conclusions

There is a strong correlation between the clinical staging of the parameter T evaluated with CT and the possible unexpected nodal upstaging. The same correlation with nodal upstaging is found for pT. At equal clinical stage, in patients affected by adenocarcinoma of the lung the relative risk of having a postoperative unexpected nodal upstaging is almost 7 times higher than in patients with squamous cell carcinoma.

Neoadjuvant systemic therapy in breast cancer: use and trends in radiotherapy practice

BACKGROUND

The use of neoadjuvant systemic therapy (nast) in the treatment of breast cancer is increasing, and the role of adjuvant radiation therapy (rt) in that setting is uncertain. We sought to review and report the use of nast, its trends over time, and its relationship with the prescribing patterns of locoregional rt in a provincial cancer system.

METHODS

Patients with stages i-iii breast cancer diagnosed during 2007-2012 were identified using a provincial database. Patient, tumour, and treatment characteristics were extracted. Multivariable logistic regression analyses were used to assess associations with the use of nast. Kaplan-Meier and Cox regression were used for survival analyses.

RESULTS

Of the 11,658 patients who met the inclusion criteria, 602 (5%) had received nast. Use of nast was more frequent in stage iii patients (53%) than in stages i and ii patients (2%). In clinically lymph-node positive patients, a pathology assessment was made approximately 50% of the time. Higher clinical tumour stage and increasing clinical nodal stage predicted for increasing use of nast and of nodal rt after nast, but pathologic nodal status after nast was not associated with use of nodal rt. A statistically significant survival difference was observed between patients in the nast and no-nast groups, but that significance disappeared in a multivariable Cox regression analysis.

CONCLUSIONS

This population-based study demonstrated 5% use of nast for breast cancer. Most patients received nodal rt after nast, and nodal rt was not associated with pathologic stage after nast. Findings likely reflect the realities of clinical practice and show that reliance on clinical nodal staging results in outcomes similar to those reported in the literature.

Preoperative 18F-FDG-PET/CT vs Contrast-Enhanced CT to Identify Regional Nodal Metastasis among Patients with Head and Neck Squamous Cell Carcinoma

Objective Our objective was to compare the accuracy of preoperative positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced CT (CECT) in detecting cervical nodal metastases in patients treated with neck dissection and to scrutinize the ability of each modality to determine nodal stage. Study Design Case series with chart review. Setting Montefiore Medical Center, Bronx, New York. Subjects and Methods Patients who underwent neck dissection at our institution for primary treatment of head and neck squamous cell carcinoma (HNSCC) and had received preoperative PET/CT and CECT were included in this study. Imaging studies were reinterpreted by 3 specialists within the field and compared for interreader agreement. Concordance between radiology and histopathology was measured using neck levels and sides, along with patient nodal stage. Sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and agreement coefficients were calculated. Results Seventy-three patients were included in the study. Sensitivity was 0.69 and 0.94 (level and side) for PET/CT vs 0.53 and 0.66 for CECT ( P = .056, P = .001). Specificity was 0.86 and 0.56 for PET/CT vs 0.91 and 0.76 for CECT ( P = .014, P = .024). No significant difference was found in overall accuracy ( P = .33, P = .88). The overall agreement percentages between N stage called by imaging modality and pathology were 52% and 55% for PET/CT and CECT, respectively. Conclusion No significant difference in sensitivity was found between PET/CT and CECT. CECT was found to have superior specificity compared with PET/CT. The information gleaned from each modality in the pretreatment evaluation of HNSCC appears to be complementary.

PET Probe-Guided Surgery in Patients with Breast Cancer: Proposal for a Methodological Approach

BACKGROUND

Although it is valuable for detecting distant metastases, identifying recurrence, and evaluating responses to chemotherapy, the role of ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) in assessing locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. In the current report, we describe a new PET probe-based clinical approach, with evaluation of the technical performance of a handheld high-energy gamma probe for intraoperative localization of breast carcinomas, and evaluation of lymph node metastases during radio-guided oncological surgery.

PATIENTS AND METHODS

Three patients underwent a PET/CT scan immediately prior to surgery following the standard clinical protocol. Intraoperatively, tumors were localized and resected with the assistance of a hand-held gamma probe. PET-guided assessment of the presence or absence of regional nodal spread of malignancy was compared with the reference standard of histopathological examination.

RESULTS

In all three cases, perioperative ¹⁸F-FDG PET/CT imaging and intraoperative gamma probe detection verified complete resection of the hypermetabolic lesions and demonstrated no additional suspicious occult disease.

CONCLUSION

This innovative approach demonstrates great promise for providing real-time access to metabolic and morphological tumor information that may lead to an optimal disease-tailored approach. In carefully selected indications, a PET probe can be a useful adjunct in surgical practice, but further trials with a larger number of patients need to be performed to verify these findings.

Spectrum Analysis of Endobronchial Ultrasound Radiofrequency of Lymph Nodes in Patients With Lung Cancer

OBJECTIVE

The aim of this study was to analyze the spectral features of the radiofrequency of lymph nodes during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and to determine its diagnostic value for detecting metastatic nodes in patients with lung cancer.

METHODS

Ultrasound spectrums of lymph nodes during EBUS-TBNA were retrospectively analyzed. A linear regression of frequency spectrum and the ultrasonic spectral parameters midband-fit, slope, and intercept were calculated. Mean values for these parameters within lymph nodes were computed. The cutoff values for each parameter for distinguishing metastatic vs benign lymph nodes were first determined within the training set; these cutoff values were then applied to the testing set for validation.

RESULTS

Overall, 362 lymph nodes (112 metastatic, 250 benign) were analyzed as the training set, and 284 lymph nodes (74 metastatic, 210 benign) were evaluated as the testing set. In the training set, all of the parameters showed a significant difference between metastatic and benign lymph nodes (P < .001). The metastatic nodes tended to show low midband-fit, high slope, and low intercept. When midband-fit and intercept were combined, the diagnostic accuracy was maximized in the training set. In the testing set, the combination of intercept and slope produced the highest diagnostic accuracy, with the following outcomes: sensitivity, 79.7%; specificity, 84.3%; diagnostic accuracy, 83.1%; positive predictive value, 64.1%; and negative predictive value, 92.2%.

CONCLUSIONS

Metastatic lymph nodes possess unique ultrasonic spectrum features, and spectrum analysis can be used as a novel diagnostic tool for differentiating between benign and malignant nodes in patients with lung cancer.

Improving the pathologic evaluation of lung cancer resection specimens

Accurate post-operative prognostication and management heavily depend on pathologic nodal stage. Patients with nodal metastasis benefit from post-operative adjuvant chemotherapy, those with mediastinal nodal involvement may also benefit from adjuvant radiation therapy. However, the quality of pathologic nodal staging varies significantly, with major survival implications in large populations of patients. We describe the quality gap in pathologic nodal staging, and provide evidence of its potential reversibility by targeted corrective interventions. One intervention, designed to improve the surgical lymphadenectomy, specimen labeling, and secure transfer between the operating theatre and the pathology laboratory, involves use of pre-labeled specimen collection kits. Another intervention involves application of an improved method of gross dissection of lung resection specimens, to reduce the inadvertent loss of intrapulmonary lymph nodes to histologic examination for metastasis. These corrective interventions are the subject of a regional dissemination and implementation project in diverse healthcare systems in a tri-state region of the United States with some of the highest lung cancer incidence and mortality rates. We discuss the potential of these interventions to significantly improve the accuracy of pathologic nodal staging, risk stratification, and the quality of specimens available for development of stage-independent prognostic markers in lung cancer.

FDG PET/CT for the preoperative nodal staging of non-small cell lung cancer in a tuberculosis-endemic country: Are maximum standardized uptake values useful?

BACKGROUND

The aim of this study was to determine an optimum standardized uptake value threshold for identifying nodal metastasis in non-small cell lung cancer (NSCLC) patients using Fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) in Taiwan, a tuberculosis-endemic country. The variation in standardized uptake values of nodal metastasis among different NSCLC histological subtypes was also evaluated.

METHODS

We retrospectively reviewed 75 NSCLC patients who had received FDG PET/CT before surgery. The diagnostic accuracy of FDG PET/CT for the preoperative nodal staging was evaluated by histopathologic findings.

RESULTS

A total of 316 nodal stations were evaluated. The sensitivity and specificity of FDG PET/CT for nodal staging were 58.6% and 81.8%, respectively, using an SUV cut-off of 2.6. With regard to the levels of mean SUVmax in true-positive and false-positive groups, there was no significant difference among different histological subtypes.

CONCLUSION

The present study demonstrated that FDG PET/CT for pre-operative nodal staging using SUVmax > 2.6 is a useful tool (with a higher specificity and a higher negative predictive value) to rule out the possibility of metastatic lymphadenopathy in operable patients with NSCLC.

The influence of nodal size on the staging of colorectal carcinomas

AIMS

The reliable identification of node negative colorectal carcinomas (CRCs) has often been linked to the histological examination of a minimum number of lymph nodes. The sizes of the lymph nodes, their metastatic status, and their number were investigated to establish whether these parameters are related, and whether their relation could help in determining the adequacy of staging.

METHODS

One thousand three hundred and thirty four negative lymph nodes, 189 metastatic lymph nodes, and 43 pericolonic/perirectal tumour deposits measuring > or = 3 mm from 60 node positive and from 63 node negative patients with CRC were assessed for size.

RESULTS

The mean size (SD) of these structures was 4.5 (2.7) mm. The lymph nodes were significantly larger in the CRCs with metastatic nodes (4.7 v 4.3 mm). Involved nodes were significantly larger than negative nodes (6.3 v 4.2 mm), despite the fact that the largest node was < or = 5 mm in one third of node positive CRCs. The examination of the seven largest nodes could have adequately staged 97% of node positive CRCs and 98% of all CRCs.

CONCLUSIONS

The nodal staging of CRCs is dependent not only on the number of lymph nodes investigated, but also on qualitative features of the lymph nodes assessed, including their size. Lymph nodes are not equivalent and any study neglecting this fact will give grounds for error in the recommendation of a minimum number of nodes for the reliable determination of node negative CRCs. Although pathologists should aim to recover all nodes, a negative nodal status based on only seven nodes can be reliable.