Feasibility of active surveillance in patients with clinically T1b papillary thyroid carcinoma ≤1.5 cm in preoperative ultrasonography: MASTER study

Objective

Active surveillance (AS) is generally accepted as an alternative to immediate surgery for papillary thyroid carcinoma (PTC) measuring ≤1.0 cm (cT1a) without risk factors. This study investigated the clinicopathologic characteristics of PTCs measuring ≤2.0 cm without cervical lymph node metastasis (cT1N0) by tumor size group to assess the feasibility of AS for PTCs between 1.0 cm and 1.5 cm (cT1b≤1.5).

Design

This study enrolled clinically T1N0 patients with preoperative ultrasonography information (n= 935) from a cohort of 1259 patients who underwent lobectomy and were finally diagnosed with PTC from June 2020 to March 2022.

Results

The cT1b≤1.5 group (n = 171; 18.3 %) exhibited more lymphatic invasion and occult central lymph node (LN) metastasis with a higher metastatic LN ratio than the cT1a group (n = 719; 76.9 %). However, among patients aged 55 years or older, there were no significant differences in occult central LN metastasis and metastatic LN ratio between the cT1a, cT1b≤1.5, and cT1b>1.5 groups. Multivariate regression analyses revealed that occult central LN metastasis was associated with age, sex, tumor size, extrathyroidal extension, and lymphatic invasion in patients under 55, while in those aged 55 or older, it was associated only with age and lymphatic invasion.

Conclusion

For PTC patients aged 55 years or older with cT1b≤1.5, AS could be a viable option due to the absence of a significant relationship between tumor size and occult central LN.

Is elective neck dissection justified in cT2N0M0 oral cavity cancer defined according to the AJCC eighth edition staging system?

BACKGROUND

The current NCCN guidelines recommend considering elective neck dissection (END) for early-stage oral cavity squamous cell carcinoma (OCSCC) with a depth of invasion (DOI) exceeding 3 mm. However, this DOI threshold, determined by evaluating the occult lymph node metastatic rate, lacks robust supporting evidence regarding its impact on patient outcomes. In this nationwide study, we sought to explore the specific indications for END in patients diagnosed with OCSCC at stage cT2N0M0, as defined by the AJCC Eighth Edition staging criteria.

METHODS

We examined 4723 patients with cT2N0M0 OCSCC, of which 3744 underwent END and 979 were monitored through neck observation (NO).

RESULTS

Patients who underwent END had better 5-year outcomes compared to those in the NO group. The END group had higher rates of neck control (95% vs. 84%, p < 0.0001), disease-specific survival (DSS; 87% vs. 84%, p = 0.0259), and overall survival (OS; 79% vs. 73%, p = 0.0002). Multivariable analysis identified NO, DOI ≥5.0 mm, and moderate-to-poor tumor differentiation as independent risk factors for 5-year neck control, DSS, and OS. Based on these prognostic variables, three distinct outcome subgroups were identified within the NO group. These included a low-risk subgroup (DOI <5 mm plus well-differentiated tumor), an intermediate-risk subgroup (DOI ≥5.0 mm or moderately differentiated tumor), and a high-risk subgroup (poorly differentiated tumor or DOI ≥5.0 mm plus moderately differentiated tumor). Notably, the 5-year survival outcomes (neck control/DSS/OS) for the low-risk subgroup within the NO group (97%/95%/85%, n = 251) were not inferior to those of the END group (95%/87%/79%).

CONCLUSIONS

By implementing risk stratification within the NO group, we found that 26% (251/979) of low-risk patients achieved outcomes similar to those in the END group. Therefore, when making decisions regarding the implementation of END in patients with cT2N0M0 OCSCC, factors such as DOI and tumor differentiation should be taken into account.

Prevalence of Occult Central Lymph Node Metastasis by Tumor Size in Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

While papillary thyroid carcinoma (PTC) is associated with high occult central neck metastasis (CNM) rates, prophylactic central neck dissection (pCND) is controversial. This meta-analysis aims to look at the occult CNM rate according to tumor size.

METHODS

A literature search was conducted in PubMed from inception to April 2023. Inclusion criteria were primary studies that determined occult CNM rates in cN0 PTC by tumor size. Heterogeneity, influential case diagnostics, and proportion data were evaluated with Cochran's Q-test, Baujat plots and Forest plots, respectively.

RESULTS

Fifty-two studies were included in this meta-analysis. The findings demonstrated an occult CNM rate of 30.3% for tumors ≤ 5 mm, 32.7% for tumors ≤ 1 cm, 46.0% for tumors between 1 and 2 cm, 43.1% for tumors between 2 and 4 cm, and 61.2% for tumors > 4 cm. The heterogeneity of each study group was high, though no publication bias was noted. While there was a trend towards increased occult CNM rates with larger tumors, comparisons between different size cutoffs varied in significance.

CONCLUSION

This comprehensive review affirms that occult CNM is high and that an ipsilateral pCND can be justified in all PTC patients for accurate differentiation between Stage I and Stage II disease and its clinical implications.

Additional Value of PET and CT Image-Based Features in the Detection of Occult Lymph Node Metastases in Lung Cancer: A Systematic Review of the Literature

Lung cancer represents the second most common malignancy worldwide and lymph node (LN) involvement serves as a crucial prognostic factor for tailoring treatment approaches. Invasive methods, such as mediastinoscopy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), are employed for preoperative LN staging. Among the preoperative non-invasive diagnostic methods, computed tomography (CT) and, recently, positron emission tomography (PET)/CT with fluorine-18-fludeoxyglucose ([¹⁸F]FDG) are routinely recommended by several guidelines; however, they can both miss pathologically proven LN metastases, with an incidence up to 26% for patients staged with [¹⁸F]FDG PET/CT. These undetected metastases, known as occult LN metastases (OLMs), are usually cases of micro-metastasis or small LN metastasis (shortest radius below 10 mm). Hence, it is crucial to find novel approaches to increase their discovery rate. Radiomics is an emerging field that seeks to uncover and quantify the concealed information present in biomedical images by utilising machine or deep learning approaches. The extracted features can be integrated into predictive models, as numerous reports have emphasised their usefulness in the staging of lung cancer. However, there is a paucity of studies examining the detection of OLMs using quantitative features derived from images. Hence, the objective of this review was to investigate the potential application of PET- and/or CT-derived quantitative radiomic features for the identification of OLMs.

Efficacy of radiomics model based on the concept of gross tumor volume and clinical target volume in predicting occult lymph node metastasis in non-small cell lung cancer

Objective

This study aimed to establish a predictive model for occult lymph node metastasis (LNM) in patients with clinical stage I-A non-small cell lung cancer (NSCLC) based on contrast-enhanced CT.

Methods

A total of 598 patients with stage I-IIA NSCLC from different hospitals were randomized into the training and validation group. The "Radiomics" tool kit of AccuContour software was employed to extract the radiomics features of GTV and CTV from chest-enhanced CT arterial phase pictures. Then, the least absolute shrinkage and selection operator (LASSO) regression analysis was applied to reduce the number of variables and develop GTV, CTV, and GTV+CTV models for predicting occult lymph node metastasis (LNM).

Results

Eight optimal radiomics features related to occult LNM were finally identified. The receiver operating characteristic (ROC) curves of the three models showed good predictive effects. The area under the curve (AUC) value of GTV, CTV, and GTV+CTV model in the training group was 0.845, 0.843, and 0.869, respectively. Similarly, the corresponding AUC values in the validation group were 0.821, 0.812, and 0.906. The combined GTV+CTV model exhibited a better predictive performance in the training and validation group by the Delong test (p<0.05). Moreover, the decision curve showed that the combined GTV+CTV predictive model was superior to the GTV or CTV model.

Conclusion

The radiomics prediction models based on GTV and CTV can predict occult LNM in patients with clinical stage I-IIA NSCLC preoperatively, and the combined GTV+CTV model is the optimal strategy for clinical application.

Programmed death ligand-1 expression and occult lymph node metastasis in non-small cell lung cancer

BACKGROUND

Identifying the preoperative risk factors for lymph node upstaging could contribute to the development of individualized perioperative treatment for patients with non-small cell lung cancer (NSCLC). The current study aimed to evaluate the risk factors for lymph node upstaging, including gene mutation and programmed death ligand-1 expression in patients with resectable NSCLC.

METHODS

Data on the clinicopathological characteristics of patients who underwent lobectomy for clinical N0 NSCLC at our institution were collected. The clinicopathological findings of the pathological N0 and lymph node upstaging groups were then analyzed. Univariate and multivariate analyses were performed to examine the predictive factors for nodal upstaging.

RESULTS

Of 291 patients, 40 had postoperative nodal upstaging (n = 25, N1; n = 15, N2). Large tumor size and high maximum standardized uptake value were significantly associated with nodal upstaging. The nodal upstaging group had a higher proportion of patients with solid adenocarcinoma and lymphatic, vascular, and pleural invasion than the pathological N0 group. Further, the nodal upstaging group had a higher proportion of patients with positive programmed death ligand-1 expression than the pathological N0 group. Univariate and multivariate analyses showed that tumor size and positive programmed death ligand-1 expression were associated with nodal upstaging.

CONCLUSION

The appropriate therapeutic strategy including preoperative treatment and resection should be cautiously considered preoperatively in patients with clinical N0 NSCLC who have large tumors and positive programmed death ligand-1 expression.

Occult lymph node metastasis in patients with laryngeal cancer and relevant predicting factors: a single-center experience

OBJECTIVE

To reveal the incidence and predictive parameters of occult cervical lymph node metastasis (LNM) in patients with cN0 laryngeal squamous cell cancer (LSCC) who underwent surgery as definitive treatment.

METHODS

Patients with cN0 laryngeal cancer who had undergone elective neck dissection together with partial or total laryngectomy between January 2006 and November 2020 were retrospectively analyzed. Clinical and histopathologic predictors of occult metastasis were also analyzed. Follow-up data were used to obtain recurrence and survival analysis.

RESULTS

A total of 86 patients with a mean age of 62.5 years were included in the study. Occult LNM was detected in 15 (17.4%) patients. Tumor grade, pT stage, thyroid cartilage invasion, and extralaryngeal extension were found to predict occult neck metastasis in univariate analysis. The mean follow-up time was 60.7 months and in the survival/recurrence analysis, pT stage, tumor location, tumor grade, presence of occult metastasis, pre-epiglottic space involvement. and extralaryngeal extension were found to predict poorer outcome.

CONCLUSION

Overall occult LNM is low (17.4%) in N0 laryngeal cancer, but the presence of LNM is a poor prognostic factor. Correct determination of the neck status and proper treatment is crucial. The incidence of LNM is very low in T1-T2 stages and well-differentiated tumors. The "wait and see" strategy may be applied in T1-T2 cases as well as selected T3 cases with well-differentiated tumors.

The Potential of MET Immunoreactivity for Prediction of Lymph Node Metastasis in Early Oral Tongue Squamous Cell Carcinoma

Objective

MET positivity is independently associated with survival in oral squamous cell carcinoma (OSCC). Since MET is a known orchestrator of invasive tumor growth, we investigated its association with LNM in early oral tongue squamous cell carcinoma (OTSCC). As it is recommended by the NCCN to use tumor depth of invasion (DOI) in making decisions on elective neck dissection (END), the results obtained for MET positivity were aligned with those for DOI > 4 mm. The cutoff value used in our institution.

Methods

Tumor samples from patients who underwent primary tumor resection and neck dissection between 1995 and 2013, were collected from the archives of the Leiden and Erasmus University Medical Center. Immunohistochemistry with D1C2 was performed to identify MET negative (< 10% uniform positivity) and MET positive (≥ 10% uniform positivity) cancers. ROC curve analysis and the Chi-squared test were used to investigate the association of MET positivity with LNM (pN+ and occult). Binary logistic regression was used to investigate the association of MET positivity with LNM.

Results

Forty-five (44.1%) of the 102 cancers were MET positive. Ninety were cN0 of which 20 were pN+ (occult metastasis). The remaining 12 cancers were cN+, of which 10 were proven pN+ and 2 were pN0. MET positivity was associated with LNM with a positive predictive value (PPV) of 44.4% and a negative predictive value (NPV) of 82.5% for pN+. For the occult group, the PPV was 36.8% and the NPV was 88.5%. Regression analysis showed that MET positivity is associated with pN+ and occult LNM (p-value < 0.05).

Conclusion

MET positivity is significantly associated with LNM in early OTSCC, outperforming DOI. The added value of MET positivity could be in the preoperative setting when END is being considered during the initial surgery. For cases with DOI ≤ 4 mm, MET positivity could aid in the clinical decision whether regular follow-up, watchful waiting, or END is more appropriate. Realizing that these preliminary results need to be independently validated in a larger patient cohort, we believe that MET positivity could be of added value in the decision making on END in early OTSCC.

Predicting occult lymph node metastasis by nomogram in patients with lung adenocarcinoma ≤2 cm

Background: Previous researches had not proposed any prediction models for occult lymph node metastasis (OLNM). Considering the occurrence of OLNM and the importance of OLNM management, we aimed to develop a nomogram to predict OLNM of patients with lung adenocarcinoma ≤2 cm. Methods: Characteristics of patients with lung adenocarcinoma of ≤2 cm diameter at the Peking Union Medical College Hospital were retrospectively reviewed. Univariate and multivariate logistic regressions were performed. A nomogram model was developed. The concordance index (C-index) and calibration and decision curves were used to evaluate the predictive ability. Results: A total of 473 patients were enrolled, with an OLNM incidence of 7.4%. Four factors were selected as risk factors. The model had a C-index of 0.932. Calibration and decision curves were determined. Conclusion: Patients with pure ground-glass opacity (pGGO) or noninvasive adenocarcinoma have significantly lower risk of OLNM. SUV_max, CEA, micropapillary and solid component were identified as independent risk factors. The nomogram model was effective in predicting OLNM preoperatively.

[Analysis and management of occult cervical lymph node metastasis of cN0 supraglottic laryngeal carcinoma]

Objective:To explore the rule of occult cervical lymph nodes metastasis in clinically node negative（cN0） supraglottic laryngeal carcinoma. Method:The clinical data of 185 patients with cN0 supraglottic laryngeal carcinoma were analyzed retrospectively. All patients received surgical resection of the primary lesions and lateral neck dissection. The survival curve was analyzed by Kaplan-Meier method, and the survival rate was compared by chi-square test and log rank test. Result:The total incidence of occult cervical lymph nodes metastasis in cN0 supraglottic laryngeal carcinoma was 38.9％（72／185）, the unilateral and bilateral neck occult metastases were determined in 51 cases（27.6%） and 21 cases（11.4%） respectively. A total of 266 positive nodes were collected, and the distributions of the 266 positive nodes were as follows: 220（82.7%） in level Ⅱ, 42（15.8%） in level Ⅲ, and 4（1.5%） in level Ⅳ. The occult metastasis rates of bilateral cervical lymph nodes with different degrees of differentiation were 37.5%（12/32） for poorly differentiated squamous cell carcinoma, 7.4%（6/81） for moderately differentiated squamous cell carcinoma, and 4.2%（3/72） for high differentiated squamous cell carcinoma; the occult metastasis rates of bilateral cervical lymph nodes at T1, T2, T3, T4 were 0, 2.7%（2/73）, 8.1%（6/74）, 46.4%（13/28）, respectively，and the difference was statistically significant（P<0.01）. Conclusion:cN0 supraglottic laryngeal carcinoma has a high rate of occult cervical lymph nodes metastasis, and its metastatic area is mainly located in level Ⅱ-Ⅲ, so the primary tumor of the laryngeal carcinoma and the neck lymph node of level Ⅱ-Ⅲ should be managed at the same time. For the cN0 patients with poorly differentiated squamous cell carcinoma or T4 staging should be treated with bilateral neck dissection.

An examination of the cutoff value of the depth of invasion for prophylactic neck dissection in stage I/II tongue cancer

Background: In stage-I/stage-II oral tongue cancer, the cutoff value of depth of invasion (DOI) for prophylactic neck dissection is controversial.Objectives: To examine the relationship between the DOI and the rate of occult lymph node metastasis. In addition, to examine the relationship between the DOI evaluated by magnetic resonance imaging (MRI) and pathological DOI.Materials and methods: In this retrospective study, 95 patients with clinical T1-2/N0M0 oral tongue cancer were enrolled. The rate of occult lymph node metastasis per DOI between 2 and 11 mm was calculated from the total pathological lymph node metastasis and delayed neck metastasis cases. We measured DOI using MRI and compared DOI obtained from pathology.Results: The total rate of occult lymph node metastasis was 23.9%. In the rate of occult lymph node metastasis per DOI, there were two peaks at point of 5 to 6 mm and 9 to 10 mm. And there was a significant correlation between the DOI evaluated by MRI and the pathological DOI (Pearson's correlation coefficient was 0.87).Conclusions and significance: There was no consistent increase in the rate of occult lymph node metastasis per DOI. MRI was a useful modality to measure the DOI.

Significance of PET-CT for Detecting Occult Lymph Node Metastasis and Affecting Prognosis in Early-Stage Tongue Squamous Cell Carcinoma

Objective: We aimed to clarify the significance of PET-CT for detecting occult lymph node metastasis and for affecting prognosis in early-stage tongue squamous cell carcinoma (SCC). Methods: Patients with surgically treated primary cT1-2N0 tongue SCC who agreed to undergo a preoperative PET-CT scan were prospectively enrolled. The primary study outcomes were occult neck lymph node metastasis and locoregional control (LRC). The Kaplan-Meier method was used to analyze the LRC rate, and then the factors that were significant in the Kaplan-Meier method were assessed in the Cox model to determine the independent factors. Results: A total of 135 patients were included, and the median maximum standardized uptake value (SUV max) of the primary tumor was 9.0. When analyzing the PET-CT results, 18 patients were recognized as having neck lymph node metastasis, and 12 patients were proven to have pathologic lymph nodes. A total of 117 patients did not have neck lymph node metastasis reported by PET-CT, and five patients were proven to have pathologic lymph nodes. The sensitivity and specificity of PET-CT for predicting occult metastasis were 70.6 and 94.9%, respectively. In patients with an SUV max ≤ 9.0, the 5-year LRC rate was 95%; in patients with an SUV max >9.0, the 5-year LRC rate was 85%, and the difference was significant. Further Cox model analyses confirmed the independence of the SUV max for predicting LRC. Conclusion: PET-CT has a high specificity for predicting occult lymph node metastasis, and an SUV max >9.0 is significantly associated with worse LRC in cT1-2N0 tongue SCC.

Development and validation of a multivariable prediction model for the identification of occult lymph node metastasis in oral squamous cell carcinoma

BACKGROUND

There have been few recent advances in the identification of occult lymph node metastases (OLNM) in oral squamous cell carcinoma (OSCC). This study aimed to develop, compare, and validate several machine learning models to predict OLNM in clinically N0 (cN0) OSCC.

METHODS

The biomarkers CD31 and PROX1 were combined with relevant histological parameters and evaluated on a training cohort (n = 56) using four different state-of-the-art machine learning models. Next, the optimized models were tested on an external validation cohort (n = 112) of early-stage (T1-2 N0) OSCC.

RESULTS

The random forest (RF) model gave the best overall performance (area under the curve = 0.89 [95% CI = 0.8, 0.98]) and accuracy (0.88 [95% CI = 0.8, 0.93]) while maintaining a negative predictive value >95%.

CONCLUSIONS

We provide a new clinical decision algorithm incorporating risk stratification by an RF model that could significantly improve the management of patients with early-stage OSCC.

18F-fluorodeoxyglucose positron emission tomography/computed tomography in the evaluation of clinically node-negative non-small cell lung cancer

One in four non-small cell lung cancer (NSCLC) patients are diagnosed at an early-stage. Following the results of the National Lung Screening Trial that demonstrated a survival benefit for low-dose computed tomography screening in high-risk patients, the incidence of early-stage NSCLC is expected to increase. Use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography during initial diagnosis of these early-stage lesions has been increasing. Traditionally, positron emission tomography/computed tomography scans have been utilized for mediastinal nodal staging and to rule out distant metastases in suspected early-stage NSCLC. In clinically node-negative NSCLC, the use of sublobar resection and selective lymph node dissection has been increasing as a therapeutic option. The higher rate of locoregional recurrences after limited resection and the significant incidence of occult lymph node metastases underscores the need to further stratify clinically node-negative NSCLC in order to select patients for limited resection versus lobectomy with complete mediastinal lymph node dissection. In this report, we review the published data, and discuss the significance and potential role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography evaluation for clinically node-negative NSCLC. Consequently, the literature review demonstrates that maximum standardized uptake value is a predictive factor for occult nodal metastasis with an accuracy of 55-77%. In addition, maximum standardized uptake value is a predictor for worse overall, as well as disease-free, survival.

Tumor budding correlates with occult cervical lymph node metastasis and poor prognosis in clinical early-stage tongue squamous cell carcinoma

BACKGROUND

Tumor budding has been suggested to be a prognostic factor in various human cancers. However, the prognostic value of tumor budding for early-stage (cT1/2N0) tongue squamous cell carcinoma remains inconclusive. This study analyzed the correlation of tumor budding with the clinicopathologic features, and its prognostic significance for cT1/2N0 stage tongue squamous cell carcinoma.

METHODS

One hundred and ninety-five patients with T1/2 stage tongue squamous cell carcinoma enrolled in the retrospective study. Tumor invasive depth, the intensity of tumor budding, and other clinicopathological features were reviewed. Overall survivals were evaluated by the Kaplan-Meier method. For multivariable analysis, Cox's proportional hazards regression models were performed.

RESULTS

The frequency of tumor buds in tongue squamous cell carcinoma is about 85.6% in this study. The intensity of tumor budding showed strong correlations with occult lymph node metastasis (P < 0.05), local relapse (P < 0.01), worse invasive pattern (P < 0.01), and invasive depth (P < 0.05). The invasive depth was significantly associated with T classification (P < 0.01) and lymph node metastasis (P < 0.01). And both high intensity of tumor budding and deeper invasive depth correlated with reduced overall survival. Cox's regression models proved tumor budding to be an independent prognostic factor in clinical early-stage tongue squamous cell carcinoma. Tumor local relapses were also a predictor of tongue squamous cell carcinoma progression.

CONCLUSIONS

Tumor budding is a frequent event in tongue squamous cell carcinoma. It independently predicted prognosis of patients with T1/2 stage tongue squamous cell carcinoma and may be used for routing pathological diagnosis and the decision of elective lymph node dissection.