Development of a novel salivary gland cancer lymph node staging system

The 8th AJCC classification is inferior to a new neck stage based on intraparotid lymph node in parotid gland cancer

BACKGROUND

Lymph node (LN) status is an important prognostic factor for parotid gland cancer (PGC). This study aimed to analyze the impact of extranodal extension (ENE) of intraparotid LN and LN metastasis burden on survival in PGC.

METHODS

Patients with surgically treated PGC and at least one metastatic cervical LN were retrospectively enrolled. Primary outcome variables were distant metastasis-free survival (DMFS), disease-specific survival (DSS), and overall survival (OS). The impact of ENE and LN metastasis burden was assessed using the Cox model.

RESULTS

A total of 292 patients were included. ENE in cervical or intraparotid LN was not associated with DMFS, DSS, or OS. Intraparotid LN metastasis had a significant impact on prognosis, and the presence of only one metastatic intraparotid LN offered an approximately 1.5-fold risk of distant metastasis. Prognostic models based on the number of positive LNs (1 vs. 2-3 vs. 4+) were superior to the AJCC N stage in terms of DMFS, DSS, and OS.

CONCLUSIONS

ENE of cervical or intraparotid LN has a limited effect on the prognosis of PGC, and the number of positive LNs is better than the AJCC N stage in LN status evaluation.

Prognostic factors for development of distant metastases in surgically treated high-grade salivary gland carcinomas: results of retrospective single center study with 213 patients

PURPOSE

Distant metastases (DM) are the primary cause of treatment failure and death of patients with salivary gland carcinomas (SGC). The purpose of present study was to evaluate factors predictive on DM development in a cohort of patients with high-grade salivary gland carcinomas.

METHODS

This was a retrospective cohort study of consecutive patients surgically treated with curative intention at the authors' institution from January 1993 to December 2018. Outcomes evaluated were overall survival (OS), disease specific survival (DSS), recurrence free survival (RFS), locoregional recurrence free survival (LRFS) and distant metastasis free survival (DMFS).

RESULTS

A total of 213 patients, 117 males (55%) and 96 females (45%), were included in the study. Parotid gland malignancies accounted for 56% of all cases. Adenoid cystic carcinoma (119 cases; 56%) was the most common tumor type. Cumulative OS for the 5-and 10-year follow-up period was 80% and 58% respectively. DM occurred with 75 patients (35%). The most common locations for DM were lung (55 cases; 73%) and liver (12 cases; 16%). Pathological nodal status, particularly the number of metastatic nodes, was the independent prognostic factor for OS, DSS, RFS and DMFS.

CONCLUSION

Number of metastatic lymph nodes, instead of extranodal extension and largest nodal diameter, was the contributing factor related to DMFS. Since the main function of staging system is to predict outcomes, the significance of extranodal extension and nodal dimension in salivary gland cancer staging system requires further clarification. The elective neck dissection could be considered therapeutic approach for high-grade SGC since occult metastases were detected in 33% of cases.

Surgery of major salivary gland cancers: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the role of surgery of the primary tumor site in the management of primary major salivary gland cancer.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group, which drafted a non-systematic narrative review of the literature published on Medline, and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Treatment of salivary gland tumor is mainly surgical. The gold standard for parotid cancer is a total parotidectomy, to obtain clear margins and remove all intraparotid lymph nodes. For low-grade tumors, partial parotidectomy with wide excision of the tumor is acceptable in the case of postoperative diagnosis on definitive histology. In the event of positive margins on definitive analysis, revision surgery should be assessed for feasibility, and performed if possible.

CONCLUSION

Treatment of primary major salivary gland cancer is based on surgery with clear resection margins, as far away as possible from the tumor. The type of surgery depends on tumor location, pathologic type and extension.

Number of positive lymph nodes affects oncologic outcomes in cN0 mucoepidermoid carcinoma of the major salivary gland

The survival significance of the number of positive lymph nodes in salivary gland carcinoma remains unclear. Thus, the current study aimed to determine the effect of the number of positive lymph nodes on disease-specific survival (DSS) and overall survival (OS) in cN0 mucoepidermoid carcinoma (MEC) of the major salivary gland. Patients surgically treated for MEC of the major salivary gland between 1975 and 2019 were retrospectively enrolled from the surveillance, epidemiology, and end results database. The total population was randomly divided into training and test groups (1:1). Primary outcome variables were DSS and OS. Prognostic models were constructed based on the independent prognostic factors determined using univariate and multivariate Cox analyses in the training group and were validated in the test group using C-index. A total of 3317 patients (1624 men and 1693 women) with a mean age of 55 ± 20 years were included. The number of positive lymph nodes was an independent prognostic factor for both DSS and OS, but the effect began when at least two positive lymph nodes for DSS and three positive lymph nodes for OS were found. Predictive models for DSS and OS in the training group had C-indexes of 0.873 (95% confidence interval [CI] 0.853-0.893) and 0.835 (95% CI 0.817-0.853), respectively. The validation of the test group showed C-indexes of 0.877 (95% CI 0.851-0.902) for DSS and 0.820 (95% CI 0.798-0.842) for OS. The number of positive lymph nodes was statistically associated with survival in cN0 major salivary gland MEC. The current prognostic model could provide individualized follow-up strategies for patients with high reliability.

Number and ratio of metastatic lymph nodes impacts the prognosis of submandibular gland cancer

This study aimed to assess the impact of the number and ratio of metastatic lymph nodes (LNs) on prognosis in submandibular gland cancer. To this end, patients were selected from the Surveillance, Epidemiology, and End Results database retrospectively. The effect of the number and ratio of metastatic LNs and the American Joint Committee on Cancer (AJCC) N stage on disease-specific survival (DSS) and overall survival (OS) was analyzed. In addition, prognostic models based on LN evaluation methods were developed to predict the OS and DSS. A total of 914 patients were included. Binary recursive partitioning analysis determined the optimal cut-off number of metastatic LNs (0 vs. 1-2. vs. 3+). The presence of 3+ metastatic LNs carried the greatest impact on prognosis, followed by 1-2 positive LNs occurrences. The ratio of metastatic LNs was an independent factor for DSS and OS. The model had a higher likelihood ratio and C-index than those in the Cox model based on the AJCC N stage. Quantitative LN burden and ratio of metastatic LNs provides better survival stratification than the AJCC N stage.

Pathological nodal status as a main predictive factor of survival and treatment outcomes of submandibular salivary gland cancers: A 25-year single center experience

INTRODUCTION

Aim of this study was to explore the survival predictive factors and treatment outcomes in a cohort of SGC patients treated at a single center over a period of 25 years.

MATERIALS AND METHODS

Patients who had received primary treatment for SGC were enroled. Outcomes evaluated were: overall survival (OS), disease specific survival (DSS), recurrence free survival (RFS), locoregional recurrence free survival (LRFS) and distant metastasis free survival (DFS).

RESULTS

A total of 40 patients with SGC were enroled in the study. The most common tumor was the adenoid cystic carcinoma (60% of cases). Cumulative OS for 5-and 10-year follow up period was 81% and 60%, respectively. Thirteen patients (32.5%) developed distant metastases during follow-up. Nodal status, high-grade histology, tumor stage and adjuvant radiation-therapy (RT) were significant variables on multivariate analysis for survival and treatment outcomes.

CONCLUSIONS

Submandibular gland carcinomas represent rare and heterogenous tumor group regarding histological appearance and locoregional and distant metastatic potential. Tumor histological grade, AJCC tumor stage and nodal status were the strongest predictive factors for survival and treatment outcomes. RT improved OS and locoregional treatment outcome, but not DFS. Elective neck dissection (END) could be beneficial for selected cases of SGC. Superselective neck dissection of levels I-IIa may be the level of dissection for END. Distant metastases were the main cause of death and treatment failure. Prognostic factors for poor DMFS were AJCC stage III and IV, high tumor grade and nodal status.

Metastatic lymph node burden impacts overall survival in submandibular gland cancer

Objective

To assess the effect of the number of positive lymph nodes (LNs) on the overall survival (OS) of patients with submandibular gland cancer (SmGC).

Methods

Patients who had undergone neck dissection for SmGC were retrospectively enrolled in this study. The effect of the American Joint Committee on Cancer (AJCC) N stage, the number of positive LNs, LN size, LN ratio, and extranodal extension (ENE) on OS and recurrence-free survival (RFS) was evaluated using Cox analysis. Prognostic models were proposed based on the identified significant variable, and their performance was compared using hazard consistency and discrimination.

Results

In total, 129 patients were included in this study. The number of positive LNs rather than LN ratio, LN size, and ENE was associated with OS. A prognostic model based on the number of positive LNs (0 vs. 1-2 vs. 3+) demonstrated a higher likelihood ratio and Harrell's C index than those according to the 7th/8th edition of the AJCC N stage in predicting OS and RFS.

Conclusions

The effect of LN metastasis on OS and RFS was mainly determined by the number of positive LNs. A validation of this finding is warranted in adenoid cystic carcinomas that were not included in this study.

Number of positive lymph nodes is superior to neck stage of the 8th AJCC in predicting prognosis in parotid mucoepidermoid carcinoma

BACKGROUND

To clarify the impact of the number of positive lymph nodes (LNs) on the prognosis of parotid mucoepidermoid carcinoma (MEC).

METHODS

Patients who underwent neck dissection for parotid MEC were retrospectively enrolled. The primary outcome variable was overall survival (OS). Associations between OS and LN factors, including the AJCC N stage, intraparotid LN metastasis, number of positive LNs, LN size, and extranodal extension (ENE), were evaluated using Cox proportional hazard regression analyses.

RESULTS

A total of 720 patients were included with a mean age of 56 ± 16 years. There was no additional survival compromise until two positive LNs were presented. After adjusting for the number of positive LNs, intraparotid LN metastasis, ENE, and LN size were not related to prognosis. Our proposed N stage based on the number of metastatic LNs (0/1 vs. 2-4 vs. 5+) showed a superior C-index to the AJCC N stage in OS prediction.

CONCLUSION

Quantitative LN burden was an important determinant of prognosis, and the proposed N stage provided better OS stratification than the AJCC N stage.

Current management and future challenges in salivary glands cancer

Salivary gland cancers (SGCs) are rare, accounting for less than 5% of all malignancies of the head and neck region, and are morphologically heterogeneous. The diagnosis is mainly based on histology, with the complementary aid of molecular profiling, which is helpful in recognizing some poorly differentiated, borderline, or atypical lesions. Instrumental imaging defines the diagnosis, representing a remarkable tool in the treatment plan. Ultrasound and magnetic resonance are the most common procedures used to describe the primary tumour. The treatment of SGCs is multimodal and consists of surgery, radiotherapy, and systemic therapy; each treatment plan is, however, featured on the patient and disease's characteristics. On 24 June 2022, in the meeting "Current management and future challenges in salivary gland cancers" many experts in this field discussed the state of the art of SGCs research, the future challenges and developments. After the meeting, the same pool of experts maintained close contact to keep these data further updated in the conference proceedings presented here. This review collects the insights and suggestions that emerged from the discussion during and after the meeting per se.

Comparative impact of grade on mortality across salivary cancers: A novel, unifying staging system

BACKGROUND

The comparative impact of histologic variants and grade has not been well described.

METHODS

Salivary cancer histologies were profiled using hospital and population-based cancer registries. Multivariable models were employed to assess relationships between histology, grade, and survival.

RESULTS

On univariate analysis, histologic variants exhibited a wide spectrum of mortality risk (5-year overall survival (OS): 86% (acinic cell carcinoma), 78% (mucoepidermoid carcinoma), 72% (adenoid cystic carcinoma), 64% (carcinoma ex-pleomorphic adenoma), 52% (adenocarcinoma NOS), and 47% (salivary duct carcinoma) (p < 0.001). However, on multivariable analysis these differences largely vanished. Worsening grade corresponded with deteriorating survival (5-year OS: 89% [low-grade], 81% [intermediate-grade], 45% [high-grade]; p < 0.001), which was upheld on multivariable analysis and propensity score matching. Recursive partitioning analysis generated TNM + G schema (c-index 0.75) superior to the existing system (c-index 0.73).

CONCLUSION

Grade represents a primary determinant of salivary cancer prognosis. Integrating grade into stage strengthens current staging systems.

Association between factor of parotid lymph node and prognosis in parotid cancer

INTRODUCTION

Survival significance of parotid lymph node (LN) factors in parotid cancer remains unclear, our goal was to assess the impact of number, size, and extranodal extension (ENE) of metastatic parotid LNs on prognosis in parotid cancer.

MATERIALS AND METHODS

Patients with surgically treated parotid cancer were retrospectively enrolled. Primary outcome variable was recurrence-free survival (RFS) and overall survival (OS). The hazard ratios (HRs) of main predictive variables including the number, size, and ENE of positive parotid LNs on RFS and OS were analyzed using Cox model. The secondary outcome variable was ENE of metastatic parotid LN, its association with clinicopathologic variables were evaluated using Chi-square test.

RESULTS

In total, 453 patients (186 male and 267 female) were included. The 10-year RFS and OS rates were 73% (95%CI: 69%-77%) and 61% (95%CI: 55%-67%), respectively. In Cox model, compared none parotid LN metastasis, one metastatic parotid LN did not offer additional compromise of RFS (p = 0.224) or OS (p = 0.135), but two or more positive LNs decreased the control of RFS (HR: 2.017; 95%CI: 1.378-4.632) and OS (HR: 2.173; 95%CI: 1.367-4.275). When accounting for the number of metastatic LNs, LN size or ENE was no longer related to RFS or OS. ENE of parotid LN tended to develop if there was presence of T3/4 stage, lymphovascular invasion, high histologic grade, N2/3 stage, and three or more positive parotid LNs.

CONCLUSION

Quantitative parotid LN burden but not ENE or LN size is an important determinant of survival in patients with parotid cancer.

Intraparotid lymph node metastasis affects distant metastasis in parotid adenoid cystic carcinoma

To evaluate the relationship between factors of metastatic intraparotid lymph node (IPLN) and distant metastasis in parotid adenoid cystic carcinoma (ACC). Patients with surgically treated parotid ACC were retrospectively enrolled, and primary outcome variable was distant metastasis free survival (DMFS). The effect of factors of metastatic IPLN on DMFS was evaluated using Cox model. In total, 232 patients were included. Extranodal extension of IPLN and cervical lymph nodes did not impact the DMFS, and the 7th but not 8th AJCC N stage was associated with DMFS. Groups of 0 and 1 metastatic IPLN had comparable DMFS, but presence of 2+ positive IPLN was related to increased worse DMFS (p = 0.034, HR 2.09). A new N stage (0 vs 1-2 vs 3+) based on total positive lymph node number exhibited better C-index than traditional N stage. IPLN metastasis increased the risk of distant metastasis, and the impact was mainly determined by the number of metastatic IPLN. Our proposed N stage provided better DMFS prediction than the 8th AJCC N classification.

Do Lymph Node Ratio and Histopathologic Parameters Have Any Prognostic Value in Primary Parotid Gland Carcinomas?

Objective

To analyze the demographic characteristics and the pathological results of neck dissection in primary parotid gland (PG) cancer patients, and to investigate the effects of histopathological parameters (perineural invasion, lymphovascular invasion, and extracapsular spread), neck metastasis, stage and lymph node ratio (LNR) on survival.

Methods

Patients who underwent parotidectomy for malignant PG tumors between 2000 and 2019 years were retrospectively reviewed from the medical records. Thirty patients who were treated with parotidectomy and neck dissection were included in the study. Lymph node ratio was calculated as the ratio of the number of metastatic lymph nodes (LN) to the total number of excised LNs. Tumor stage, regional LN metastasis, LNR, perineural invasion, lymphovascular invasion, and extracapsular spread were reviewed for the effects on survival with the Kaplan-Meier analysis.

Results

The study included 17 (57%) male and 13 (43%) female patients. Their mean age was 67.93±16.90 years (range, 50-85 years). The average number of the excised LN was 26.03±11.79 (range, 3-50). Mean LNR was 0.16±0.26. The Kaplan-Meier analysis showed that neck metastasis (p=0.001) and LNR (p<0.001) were associated with shorter survival times compared to perineural invasion (p=0.818), lymphovascular invasion (p=0.154), extracapsular spread (p=0.410) and stage (p=0.294). In multivariate COX regression analysis, only LNR had a statistically significant difference (p=0.027) compared to the other parameters.

Conclusion

The present study suggests that LNR and neck metastasis are associated with shorter survival times in PG cancers. Lymph node ratio can be used as a prognostic marker in these patients.

Number of positive lymph nodes affects outcomes in parotid adenoid cystic carcinoma

Objectives

Survival significance of the number of positive lymph nodes (LNs) in parotid adenoid cystic carcinoma (ACC) remains unknown; thus, this study aimed to determine the impact of the number of positive LNs on the prognosis of parotid ACC.

Methods

Patients with surgically treated parotid ACC were enrolled from the SEER database. The number of positive LNs was analyzed using three models (0 vs 1+, 0 vs 1 vs 2 vs 3 vs 4 vs 4 vs 5 vs 6+, 0/1 vs 2-4 vs 5+), its hazard ratios on disease specific survival (DSS) and overall survival (OS) were assessed using univariate and multivariate Cox analyses.

Results

A total of 1,689 patients were included. In all models, the number of positive LNs was independently related to DSS and OS, model 3 had the highest C-index for DSS [0.83 (95% CI: 0.81-0.85)] and OS [0.82 (95% CI: 0.80-0.84)]. Compared with the 0/1 positive LN group, the 2-4 positive LN group had an HR of 2.81 (95% CI: 1.73-4.56) for DSS and 2.36 (95% CI: 1.58-3.54) for OS. The 5+ LN group had an HR of 20.15 (95% CI: 7.50-54.18) for DSS and 14.20 (95% CI: 5.45-36.97) for OS. No overlap existed in the 95% CI of the HR.

Conclusions

The three prognostic categories based on the number of positive LNs (0/1 vs 2-4 vs 5+) could stratify the DSS and OS in parotid ACC without overlap.

A nomogram involving immune-inflammation index for predicting distant metastasis-free survival of major salivary gland carcinoma following postoperative radiotherapy

BACKGROUND

Postoperative radiotherapy (PORT) is beneficial in the improvement of local-regional control and overall survival (OS) for major salivary gland carcinomas (SGCs), and distant metastasis remained the main failure pattern. This study was designed to develop a nomogram model involving immune-inflammation index to predict distant metastasis-free survival (DMFS) of major SGCs.

PATIENTS AND METHODS

A total of 418 patients with major SGCs following PORT were randomly divided into a training (n = 334) and validation set (n = 84). The pre-radiotherapy neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were calculated and transformed as continuous variables for every patient. Associations between DMFS and variables were performed by univariate and multivariable analysis using Log-rank and Cox regression methods. A nomogram was constructed based on the prognostic factors identified by the Cox hazards model. The decision curve analysis (DCA) was conducted with the training and validation set.

RESULTS

The estimated 3-, 5-, and 10-year DMFS were 79.4%, 71.8%, and 59.1%, respectively. The multivariate analysis revealed that age (p = 0.033), advanced T stage (p = 0.003), positive N stage (p < 0.001), high-risk pathology (p = 0.011), and high PLR (p = 0.001) were significantly associated with worse DMFS. The nomogram showed good calibration and discrimination in the training (AUC = 80.9) and validation set (AUC = 87.9). Furthermore, the DCA demonstrated favorable applicability, and a significant difference (p < 0.001) was observed for the DMFS between the subgroups based on the nomogram points.

CONCLUSION

The nomogram incorporating clinicopathological features and PLR presented accurate individual prediction for DMFS of the patients with major SGCs following PORT. Further external validation of the model is warranted for clinical utility.

Nodal Metastasis Count and Oncologic Outcomes in Head and Neck Cancer: A Secondary Analysis of NRG/RTOG 9501, NRG/RTOG 0234, and EORTC 22931

PURPOSE

A better understanding of the relationship between the spread of head and neck squamous cell carcinoma (HNSCC) to regional lymph nodes (LNs) and the frequency and manner of treatment failure should help design better treatment intensification strategies. In this study, we evaluated the relationship between recurrence patterns, mortality, and number of pathologically positive (+) LNs in HNSCC in 3 prospective randomized controlled trials.

METHODS AND MATERIALS

We performed a secondary analysis of 947 patients with HNSCC enrolled in RTOG 9501 (n = 410), RTOG 0234 (n = 203), and EORTC 22931 (n = 334) undergoing surgery and postoperative radiation ± systemic therapy. Multivariable models were constructed for overall survival (OS), disease-free survival (DFS), locoregional relapse (LRR), and distant metastases (DM). Restricted cubic splines were used to model the nonlinear relationship between +LN number and outcomes.

RESULTS

In multivariable analysis, OS and DFS decreased with each +LN without plateau, most pronounced up to 5 +LNs (OS: hazard ratio [HR], 1.21 per +LN; 95% confidence interval [CI], 1.10-1.34; P < .001; DFS: HR per +LN, 1.19; 95% CI, 1.08-1.30; P < .001) and more gradually beyond this (OS: HR per +LN, 1.02; 95% CI, 1.01-1.06; P < .001; DFS: HR per +LN, 1.04; 95% CI, 1.02-1.06; P < .001). In contrast to LRR risk, which increased sharply up to 5 +LNs (HR per +LN, 1.28; 95% CI, 1.10-1.50; P < .001) but plateaued beyond this (HR per +LN, 1.00; 95% CI, 0.96-1.04; P = .98), DM risk increased continuously with increasing +LNs (≤5 +LNs: HR per +LN, 1.10; 95% CI, 1.01-1.20; P = .04; >5 +LNs: HR per +LN, 1.05; 95% CI, 1.02-1.08; P = .003).

CONCLUSIONS

In high-risk resected HNSCC, increased mortality was associated with increased +LN count. LRR and DM risk both increased in parallel up to 5 +LNs, but only DM continued to increase for further +LN increases. These differing recurrence patterns can help inform design of future treatments.

Quantitative Nodal Burden and Mortality Across Solid Cancers

BACKGROUND

Nodal staging systems vary substantially across solid tumors, implying heterogeneity in the behavior of nodal variables in various contexts. We hypothesized, in contradiction to this, that metastatic lymph node (LN) number is a universal and dominant predictor of outcome across solid tumors.

METHODS

We performed a retrospective cohort analysis of 1 304 498 patients in the National Cancer Database undergoing surgery between 2004 and 2015 across 16 solid cancer sites. Multivariable Cox regression analyses were constructed using restricted cubic splines to model the association between nodal number and mortality. Recursive partitioning analysis (RPA) was used to derive nodal classification systems for each solid cancer based on metastatic LN count. The reproducibility of these findings was assessed in 1 969 727 patients from the Surveillance, Epidemiology, and End Results registry. Two-sided tests were used for all statistical analyses.

RESULTS

Consistently across disease sites, mortality risk increased continuously with increasing number of metastatic LNs (P < .001 for all spline segments). Each RPA-derived nodal classification system produced multiple prognostic groups spanning a wide spectrum of mortality risk (P < .001). Multivariable models using these RPA-derived nodal classifications demonstrated improved concordance with mortality compared with models using American Joint Committee on Cancer staging in sites where nodal classification is not based on metastatic LN count. Each RPA-derived nodal classification system was reproducible in a large validation cohort for all-cause and cause-specific mortality (P < .001). High quantitative nodal burden was the single strongest tumor-intrinsic variable associated with mortality in 12 of 16 disease sites.

CONCLUSIONS

Quantitative metastatic LN burden is a fundamental driver of mortality across solid cancers and should serve as a foundation for pathologic nodal staging across solid tumors.

Salivary Gland Function, Development and Regeneration

Salivary glands produce and secrete saliva, which is essential for maintaining oral health and overall health. Understanding both the unique structure and physiological function of salivary glands, as well as how they are affected by disease and injury will direct the development of therapy to repair and regenerate them. Significant recent advances, particularly in the OMICS field, increase our understanding of how salivary glands develop at the cellular, molecular and genetic levels; the signaling pathways involved, the dynamics of progenitor cell lineages in development, homeostasis and regeneration and the role of the extracellular matrix microenvironment. These provide a template for cell and gene therapies as well as bioengineering approaches to repair or regenerate salivary function.

[Application of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma]

OBJECTIVE

To investigate the effectiveness of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma (PGC).

METHODS

Between June 2010 and June 2020, 32 patients with advanced local lesions of PGC were treated with extended radical resection. After that, 17 patients were repaired with the free peroneal artery chimeric perforator flaps (trial group) and another 15 patients were repaired with the pedicled pectoralis major myocutaneous flaps (control group). There was no significant difference in gender, age, disease type, histopathological classification, clinical stage, and pathological stage between groups ( P>0.05). The size of skin flap in trial group ranged from 7 cm×6 cm to 12 cm×8 cm and the size of soleus muscle flap ranged from 5 cm×3 cm to 6 cm×4 cm. The donor sites were repaired with skin grafting. The size of the pedicled pectoralis major myocutaneous flaps in control group ranged from 9 cm×6 cm to 14 cm×7 cm. The donor sites were sutured directly. The operation time, survival rate of flap, and postoperative survival of patients were recorded and compared between groups. At 1 year after operation, the University of Washington quality of life (UW-QOL) questionnaire was used to evaluate the quality of life of patients in the two groups, including appearance, shoulder movement, sociability, masticatory function, speech function, and mood.

RESULTS

The operations completed successfully. The operation time was (6.19±0.72) hours in trial group and (6.41±0.71) hours in control group, showing no significant difference between groups ( t=-0.863, P=0.395). The survival rate of flap in trial group was 94.1% (16/17); and 1 patient suffered from vascular crisis after operation and was replaced with the pedicled pectoralis major myocutaneous flap. The survival rate of flap in control group was 100%. All grafts survived and the incisions healed by first intention in the two groups. All patients were followed up. The follow-up time was 6-60 months (median, 60 months) in trial group and 7-60 months (median, 60 months) in control group. Cumulative survival rates of patients at 1, 3, and 5 years after operation were 94.1%, 64.7%, and 58.8% in trial group, respectively; 86.7%, 66.7%, and 53.3% in control group, respectively. There was no significant difference in the cumulative survival rate between groups ( χ ²=0.090, P=0.762). According to the UW-QOL questionnaire at 1 year after operation, the scores of appearance, shoulder movement, sociability, and mood in trial group were significantly higher than those in control group ( P<0.05); and there was no significant difference in masticatory function and speech function scores between groups ( P>0.05).

CONCLUSION

The peroneal artery perforator has an invariable anatomical relationship. Each perforator emits the muscular branch that nourishes the soleus muscle. Therefore, personalized free peroneal artery chimeric perforator flap can be designed according to the tissue defect, and used to repair the defect after advanced local lesions resection in PGC.

Development and Validation of a Modified Pathologic Nodal Classification System for Cutaneous Melanoma

Importance

Given the evolving patterns of lymph node evaluation for cutaneous melanoma, it is unclear whether the current nodal classification system will continue to accurately reflect prognosis in the modern era. Existing nodal staging for cutaneous melanoma was developed primarily for patients undergoing completion lymph node dissection (CLND) for node-positive disease and does not produce groups with continuously increasing mortality.

Objective

To develop and validate a modified nodal classification system for cutaneous melanoma.

Design, Setting, and Participants

This retrospective cohort analysis included 105 785 patients with cutaneous melanoma undergoing surgery and nodal evaluation from January 1, 2004, to December 31, 2015, in the National Cancer Database. Extent of lymph node dissection was available for patients diagnosed in 2012 and onward. Multivariable models were generated with number of positive lymph nodes modeled using restricted cubic splines. A modified nodal classification system was derived using recursive partitioning analysis (RPA). The proposed lymph node classification system was validated in 85 499 patients from the Surveillance, Epidemiology, and End Results (SEER-18) database. Data were analyzed from April 9, 2020, to May 28, 2021.

Main Outcomes and Measures

Overall survival.

Results

Among the 105 785 patients included in the analysis (62 496 men [59.1%]; mean [SD] age, 59.9 [15.5] years), number of positive lymph nodes (hazard ratio [HR] per lymph node for 0 to 2 positive lymph nodes, 2.48 [95% CI, 2.37-2-61; P < .001]; HR per lymph node for ≥3 positive lymph nodes, 1.10 [95% CI 1.07-1.13; P < .001]), clinically detected metastases (HR, 1.35; 95% CI, 1.27-1.42; P < .001), and in-transit metastases (HR, 1.48; 95% CI, 1.34-1.65; P < .001) were independently associated with mortality. An RPA-derived system using these variables demonstrated continuously increasing mortality for each proposed lymph node classification group, with HRs of 1.83 (95% CI, 1.76-1.91) for N1a, 2.72 (95% CI, 2.58-2.86) for N1b, 3.79 (95% CI, 3.51-4.08) for N2a, 4.56 (95% CI, 4.22-4.92) for N2b, 6.15 (95% CI, 5.59-6.76) for N3a, and 8.25 (95% CI, 7.64-8.91) for N3b in the proposed system (P < .001). By contrast, the current American Joint Committee on Cancer (AJCC) nodal classification system produced a more haphazard mortality profile, with HRs of 1.83 (95% CI, 1.76-1.91) for N1a, 3.81 (95% CI, 3.53-4.12) for N1b, 2.59 (95% CI, 2.30-2.93) for N1c, 2.71 (95% CI, 2.56-2.87) for N2a, 4.51 (95% CI, 4.17-4.87) for N2b, 3.44 (95% CI, 2.60-4.55) for N2c, 6.06 (95% CI, 5.51-6.67) for N3a, 8.15 (95% CI, 7.54-8.81) for N3b, and 6.90 (95% CI, 5.60-8.49) for N3c. As a sensitivity analysis, the proposed system continued to accurately stratify patients when excluding those undergoing CLND for microscopic lymph node metastases. This system was validated for overall survival and cause-specific mortality in SEER-18. Last, a new overall staging system for node-positive patients was developed by RPA and demonstrated improved concordance vs the AJCC, 8th edition system (C statistic, 0.690 [95% CI, 0.689-0.691] vs 0.666 [95% CI, 0.666-0.668]).

Conclusions and Relevance

The findings of this cohort study suggest that a modified nodal classification system can accurately stratify mortality risk in cutaneous melanoma in an era of increasing use of sentinel lymph node biopsy without CLND and should be considered for future staging systems.

Impact of tumor site on the prognosis of salivary gland neoplasms: A systematic review and meta-analysis

In numerous types of cancer, the primary tumor site can show a correlation with disease behavior and survival outcomes. In salivary gland tumors (SGTs) this association remains controversial. This study assessed the association between primary sites of SGTs and prognosis. Studies from five databases were assessed and a meta-analysis was performed using studies that presented 95 % confidence interval (95 % CI), hazard ratio (HR) and survival analysis. Gathered information from 46,361 patients showed that site had a prognostic impact on SGTs. Tumors involving minor salivary glands showed worse overall survival (HR = 1.60; 95 % CI = 1.17-2.19; p = 0.003), disease-specific survival (HR=1.63; 95 % CI = 1.12-2.37; p = 0.01), and cause-specific survival (HR=2.10; 95 % CI = 1.72-2.55; p = 0.00001). Tumors from major salivary glands showed better recurrence-free survival (HR=2.31; 95 % CI = 1.77-3.02; p = 0.00001), and locoregional control of disease (HR=2.66; 95 % CI = 1.20-5.91; p = 0.02). Our results showed that the primary site of SGTs has an impact on patient prognosis.

The impact of nodal status in major salivary gland carcinoma: A multicenter experience and proposal of a novel N-classification

OBJECTIVES

Despite differences in oncological behavior, the 8th edition of AJCC TNM staging currently proposes the same N-classification for major salivary glands (MSG) carcinoma and squamous cell carcinoma of the upper aerodigestive tract. The present study aims to investigate a more reliable definition of N-categories for MSG carcinoma.

MATERIALS AND METHODS

A retrospective multicenter study was performed, including 307 patients treated for primary MSG carcinoma from 1995 to 2019. Outcome measures included overall survival (OS), disease specific survival, and local, regional, and distant recurrence. Survival analysis was performed using log-rank test and Cox proportional-hazards model. Overall number (ON) and largest diameter (LD) of nodal metastases, including intra-parotid metastases, were considered to develop three novel proposals of N-classification; their performance were compared with the current TNM staging using Akaike information criterion (AIC), Bayesian information criterion (BIC), and Nagelkerke pseudo-R2.

RESULTS

Intra-parotid nodes, ON and LD of nodal metastases emerged as major prognosticators for OS, while extra-nodal extension did not impact on any survival. The current N-classification did not show a satisfactory OS stratification. Three novel N-classifications were developed according to number of metastatic nodes (0 vs 1-3 vs ≥ 4) and/or their maximum diameter (<20 mm vs ≥ 20 mm). They all showed better accuracy in OS stratification, and achieved better AIC, BIC and Nagelkerke pseudo-R2 indices when compared to current N-classification.

CONCLUSION

All the proposed N-classifications improved OS stratification and could help in defining a specific N-classification for MSG carcinoma. Their validation and assessment in an external cohort is needed.

Diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in sublingual and submandibular salivary gland tumors

The aim of the present study was to compare the diagnostic accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) with that of conventional imaging studies (CIS), such as CT or magnetic resonance imaging (MRI), in the clinical diagnosis and staging of submandibular and sublingual salivary gland tumors. In addition, the data obtained were used to evaluate the significance of maximum standardized uptake value (SUVmax) in diagnosing benign or malignant lesions. For the present study, 18 patients with submandibular or sublingual neoplasms underwent F-18 FDG PET/CT imaging with accompanying CT or MRI. The diagnostic values from 43 F-18 FDG PET/CT scans and 28 CIS of the 18 patients were compared to the gold standard histopathological and/or cytopathological diagnosis. The results demonstrated that the diagnostic accuracy for predicting primary tumors was similar between F-18 FDG PET/CT and CIS. By contrast, PET/CT imaging was more accurate in detecting lymph node metastasis compared with CT or MRI (95.4 vs. 66.7%). F-18 FDG PET/CT had a sensitivity of 88.9% and a specificity of 97.1%, whereas CT or MRI had a sensitivity of 54.5% and a specificity of 75.0%. F-18 FDG PET/CT also enabled screening for distant metastasis, as observed in 10 cases in the present study. Furthermore, there were no significant differences in SUVmax between benign or malignant salivary gland lesions, as high glucose metabolism was also observed in benign tumors. In conclusion, F-18 FDG PET/CT provides more accurate diagnostic information for the evaluation of submandibular and sublingual salivary gland tumors as compared with CIS in terms of lymph node and distant metastasis.

Preoperative evaluation and treatment consideration of parotid gland tumors

BACKGROUND

The nature of parotid tumors often remains unknown preoperatively and final histopathology may reveal unexpected malignancy. Still, the use of fine-needle aspiration cytology (FNAC) and imaging varies in the management of these tumors.

METHODS

We evaluated the preoperative examinations and management of all 195 parotid gland tumors diagnosed within our catchment area of 1.6 million people during 2015.

RESULTS

Altogether 171 (88%) tumors were classified as true salivary gland neoplasms. FNAC showed no false malignant findings, but it was false benign in 5 (2.6%) cases. Preoperative MRI was utilized in 48 patients (25%). Twenty (10%) malignancies included 16 salivary gland carcinomas. Pleomorphic adenomas accounted for 52% of all adenomas. For 24 (40%) Warthin tumors, surgery was omitted.

CONCLUSION

The proportion of malignancies was lower than generally presented. Our proposed guidelines include ultrasound-guided FNAC with certain limitations. MRI is warranted in selected cases, but seems unnecessary routinely.

Development and validation of a prognostic model incorporating [18F]FDG PET/CT radiomics for patients with minor salivary gland carcinoma

OBJECTIVES

The aim of this study was to develop and validate a prognostic model incorporating [¹⁸F]FDG PET/CT radiomics for patients of minor salivary gland carcinoma (MSGC).

METHODS

We retrospectively reviewed the pretreatment [¹⁸F]FDG PET/CT images of 75 MSGC patients treated with curative intent. Using a 1.5:1 ratio, the patients were randomly divided into a training and validation group. The main outcome measurements were overall survival (OS) and relapse-free survival (RFS). All of the patients were followed up for at least 30 months or until death. Following segmentation of tumors and lymph nodes on PET images, radiomic features were extracted. The prognostic significance of PET radiomics and clinical parameters in the training group was examined using receiver operating characteristic curve analysis. Variables showing a significant impact on OS and RFS were entered into multivariable Cox regression models. Recursive partitioning analysis was subsequently implemented to devise a prognostic index, whose performance was examined in the validation group. Finally, the performance of the index was compared with clinical variables in the entire cohort and nomograms for surgically treated cases.

RESULTS

The training and validation groups consisted of 45 and 30 patients, respectively. The median follow-up time in the entire cohort was 59.5 months. Eighteen relapse, 19 dead, and thirteen relapse, eight dead events were found in the training and validation cohorts, respectively. In the training group, two factors were identified as independently associated with poor OS, i.e., (1) tumors with both high maximum standardized uptake value (SUV_max) and discretized intensity entropy and (2) poor performance status or N2c-N3 stage. A prognostic model based on the above factors was devised and showed significant higher concordance index (C-index) for OS than those of AJCC stage and high-risk histology (C-index: 0.83 vs. 0.65, P = 0.005; 0.83 vs. 0.54, P < 0.001, respectively). This index also demonstrated superior performance than nomogram for OS (C-index: 0.88 vs. 0.70, P = 0.017) and that for RFS (C-index: 0.87 vs. 0.72, P = 0.004).

CONCLUSIONS

We devised a novel prognostic model that incorporates [¹⁸F]FDG PET/CT radiomics and may help refine outcome prediction in patients with MSGC.

Positive lymph node number and extranodal extension for predicting recurrence and survival in patients with salivary gland cancer

BACKGROUND

This study compared our proposed N classification including the addition of the number of positive lymph node (LN+) and extranodal extension (ENE) with the current and previous American Joint Committee on Cancer (AJCC) N classifications in salivary gland cancer (SGC).

METHODS

This study involved 172 SGC patients who underwent surgery. Cox proportional hazard regression analyses were used to identify factors associated with overall survival (OS) and disease-free survival (DFS).

RESULTS

In multivariate analyses, LN+ number, LN ratio, and ENE were associated with OS and DFS outcomes (all P < .05). Our new N classification proposed three categories: N0 (0 LN+), N1 (1 LN+), and N2 (≥2 LN+ or ENE). The C-index of our N classification showed improvement in OS prediction (0.768) compared with the AJCC seventh (0.743) and eighth (0.756) edition N classifications.

CONCLUSIONS

Our proposed N classification incorporating LN+ number and ENE may improve prediction of post-treatment survival and recurrence in patients with SGC.

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.

Lymph node ratio predictive of recurrence, distant metastasis, and survival in submandibular gland carcinoma patients

PURPOSE

Submandibular gland (SMG) carcinoma has an unfavorable clinical course and a low survival rate. Specific tumor and nodal findings might help predict posttreatment recurrence and survival in SMG carcinoma patients. This study evaluated factors predictive of posttreatment recurrence and survival in SMG carcinoma patients.

METHODS

This study enrolled 99 consecutive patients with previously untreated SMG carcinoma. All patients underwent tumor and metastatic lymph node resection along with or without radiation/chemo-radiation. The predictive clinical and pathological factors for disease-free survival (DFS), distant metastasis-free survival (DMFS), disease-specific survival (DSS), and overall survival (OS) were determined using univariate and multivariate Cox proportional hazards regression analyses.

RESULTS

The median tumor size was 2.7 cm and 53 patients (53.5%) had high-grade tumors. The rates of initial nodal and distant metastasis at initial presentation or follow-up were 45.5% and 42.4%, respectively. The actuarial 5-year DFS, DMFS, DSS, and OS rates were 46.4%, 55.9%, 61.5%, and 59.7%, respectively. The independent factors associated with poor DFS, DMFS, DSS, and OS outcomes (all p < 0.05) were T3-T4 classification and lymph node ratio. A histological high-grade tumor was an independent prognostic factor predictive of poor DMFS, DSS, and OS outcomes (all p < 0.05).

CONCLUSIONS

A high rate of distant site failure is associated with SMG carcinoma, resulting in a poor survival rate. Lymph node ratio might help predict recurrence, distant metastasis, and death due to SMG carcinoma.