Pediatric Salivary Cancer: Epidemiology, Treatment Trends, and Association of Treatment Modality with Survival

Clinical features and prognostic factors for malignant parotid tumors in children and adolescents: A population-based study

PURPOSE

We performed a population-based cohort study to investigate the clinical characteristics and survival rates of primary malignant parotid tumors (MPT) in children and adolescents.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify all pediatric and adolescent patients with MPT who were diagnosed between 2000 and 2018. Based on a number of parameters, survival curves were produced using Kaplane-Meier estimates. The log-rank test was used to compare survival curves. The influence of each component on overall survival (OS) was examined using a multivariate Cox proportional hazards model.

RESULTS

There were 352 identified pediatric and adolescent patients with MPT. At diagnosis, the age ranged from 1.0 to 19 years, with a median of 15 years. Mucoepidermoid carcinoma (MC) (46.5 %) was the most common histological subtype, followed by acinar cell carcinoma (ACC) (36.4 %) and others (17.1 %) such as adenoid cystic carcinoma and squamous cell carcinoma. All patients had overall survival rates of 98.8 %, 95.6 %, and 94.6 % at 1-year, 3-year and 5-year, respectively. The results of the Cox proportional hazard regression showed that tumor grade, SEER stage, radiotherapy, and treatment regimens were significant independent predictors of overall survival.

CONCLUSIONS

In pediatric and adolescent MPT, tumor grade, SEER stage, adjuvant radiation, and treatment regimens were found to be important independent predictors of survival. More research is required to validate the role of adjuvant radiation.

Pediatric primary salivary gland tumors

OBJECTIVES

To characterize the presentation and treatment of children presenting with primary salivary gland neoplasms.

METHODS

A retrospective review of primary salivary tumor patients presenting to Children's Hospital Colorado between January 2000 and August 2020.

RESULTS

Fifty children were identified with primary salivary gland tumors, comprising of 39 (78 %) benign and 11 (22 %) malignant lesions. Pleomorphic adenoma was the most common benign tumor (36/39, 92 %), while acinic cell carcinoma was the most common malignancy (7/11, 64 %). The parotid gland was the most common site, followed by the submandibular gland (66 % vs. 34 %). No tumors were found in the sublingual glands. Benign neoplasms accounted for 70 % of parotid lesions and 94 % of submandibular tumors. No significant differences in age (13.6 years, SD 4 vs. 13.0 years, SD 4.3) were noted between patients with benign and malignant disease, but tumors in females were more frequently malignant (M:F 1:1.3 vs. 1:2.7 for benign and malignant tumors, respectively). Neck dissection and/or facial nerve sacrifice were required in 27 % (3/11) and 9.1 % (1/11) of malignancies, respectively. Local recurrence was observed in 7.7 % (3/39) of benign cases and 9.1 % (1/11) of malignant cases. No salivary malignancies required chemotherapy, though one patient with neurofibromatosis received imatinib prior to resection. Two patients with locoregional malignancy received adjunctive radiation. The average duration of follow up for benign and malignant disease were 12.6 ± 25 and 45.1 ± 32 months, respectively.

CONCLUSIONS

This study presents one of the larger single institutional experiences of pediatric primary salivary neoplasms in the past 20 years, identifying pleomorphic adenoma and acinic cell carcinoma as the most common benign and malignant etiologies, respectively. While this review found most neoplasms presented as a localized mass effectively managed with conservative surgical resection, aggressive tumors required multidisciplinary care.

Exploring the Epidemiology and Survival Trends in Pediatric Major Salivary Gland Malignancies: Insights from the National Cancer Database

OBJECTIVE

To investigate the clinicopathological, therapeutic, and survival data on pediatric major salivary gland cancers.

MATERIALS AND METHODS

National Cancer Database (NCDB) query from 2004 to 2018.

RESULTS

In total, 967 cases of individuals under the age of 21 were identified. Most cancers affected the parotid gland (86%). Mucoepidermoid carcinoma (41.3%) and acinic cell adenocarcinoma (33.6%) were the most common. Tumors occurred more often from age 11 to 21, and females were more affected. Histology varied by age, gender, and race. In the 0-5 age group, mucoepidermoid carcinoma and myoepithelial carcinoma/sarcoma/rhabdomyosarcoma were the most common pathologies. In patients over 5 years old, mucoepidermoid carcinoma was the most frequent tumor in boys, while acinic cell adenocarcinoma was more common in girls. African American patients had a higher incidence of mucoepidermoid carcinoma, while White patients in the 0-5 age group had a higher incidence of myoepithelial carcinoma/sarcoma/rhabdomyosarcoma tumors. Low-grade tumors were commonly diagnosed at stage I, but the 0-5 age group had a high frequency of stage IV tumors. The overall 5-year survival rate was 94.9%, with 90% for the 0-5 years age group and 96% for the 11-15 years age group. Negative margins were associated with higher 5-year survival rates in high-stage tumors (93%) compared to positive margins (80%). Submandibular malignancies had worse 5-year survival rates across all age groups.

CONCLUSIONS

Major salivary gland malignancies in pediatric patients exhibit variations in histopathologic characteristics by age, gender, and race. Negative margins impact 5-year survival rates, especially in high-stage tumors.

Surgical management of pediatric salivary malignant tumors-A single-center cohort study

BACKGROUND

The purpose of this study was to report incidence, clinicopathologic behavior, management, and outcome of pediatric patients treated surgically for salivary gland (SG) malignancies.

METHODS

Patients who underwent surgery for SG malignancies from 1985 to 2015 were identified. Clinical, pathological, treatment and outcomes data were collected. Disease-specific survival (DSS), recurrence-free survival (RFS), and overall survival (OS) were calculated using Kaplan-Meier method.

RESULTS

Twenty-eight pediatric patients were included. The most common histopathological types were mucoepidermoid (n = 18, 64.3%), acinic cell (n = 7, 25.0%), adenoid cystic (n = 2, 7.1%), and adenocarcinoma (n = 1, 3.6%). Surgical approach varied and ranged from superficial parotidectomy (n = 11, 39.3%) to partial maxillectomy (n = 6, 21.4%). Nine patients (32%) required postoperative radiotherapy. DSS, OS, and RFS probability at 5 years were 96.4%, 96.4%, and 89.3%, respectively.

CONCLUSION

Pediatric SG malignancies are rare and have favorable outcome at 5 years. Larger, multi-institutional studies are required to better understand the natural history of these rare tumors.

Pediatric parotidectomy outcomes: A 14-year multicenter study

Objectives

Parotidectomy increases childhood challenges. This study aimed to determine the clinical profiles, investigations, and outcomes of pediatric patients who had undergone parotidectomy.

Methods

A multicenter retrospective review of parotidectomy in pediatric patients between 2007 and 2020.

Results

In 108 parotidectomies, the final diagnoses were benign (47.22%), malignant (36.11%), and non-neoplastic (16.67%). The incidence of facial palsy was 37.03%, which was significantly lower in the superficial group than that in the total parotidectomy group (p = .021). The incidence of facial nerve palsy was significantly higher in the malignancy group than that in the benign group (p = .035). Magnetic resonance imaging (MRI) detected malignancy with 92.8% overall accuracy, 83.3% sensitivity, and 100% specificity. The sensitivity and specificity of fine-needle aspiration (FNA) were 54.2% and 92.7%, respectively.

Conclusions

Parotidectomy is commonly performed for benign and non-neoplastic diseases in pediatric patients. Facial nerve palsy is significantly associated with malignant tumors and total parotidectomy. MRI is the most accurate imaging modality for diagnosing malignant lesions. FNA exhibits moderate agreement with the final pathology.

Level of Evidence

Level IV.

Imaging of parotid anomalies in infants and children

A wide spectrum of disorders involves the parotid glands, in infancy and childhood. Acute or chronic inflammatory/infectious diseases are predominant. The first branchial cleft anomalies are congenital lesions that typically manifest during childhood. Tumor lesions are more likely to be benign, with infantile hemangioma the most common in infancy and pleomorphic adenoma the most frequent in childhood. Malignant tumors are uncommon, with mucoepidermoid carcinoma the least rare. Infiltrative parotid diseases are rare and have some pediatric clinical specificities. These common and uncommon disorders of parotid glands during childhood and their imaging characteristics are reviewed.

Rethinking the Definition of High Risk in Pediatric Salivary Gland Carcinoma

OBJECTIVE

Indications for adjuvant radiation in pediatric salivary gland carcinoma rely on high-risk criteria extrapolated from adult data. We sought to determine whether adult-derived high-risk criteria were prognostic in children aged ≤21 years or young adults aged 22 to 39 years.

STUDY DESIGN

Cross-sectional analysis of a hospital-based national registry.

SETTING

Patients were identified from the National Cancer Database between 2004 and 2015.

METHODS

High-risk criteria were defined as adenoid cystic histology, intermediate/high grade, T3/T4, positive margins, and/or lymph node involvement. Exact matching was used to adjust for differences in baseline characteristics between pediatric and young adult patients.

RESULTS

We identified 215 pediatric patients aged ≤21 years, 317 patients aged 22 to 30 years, and 466 patients aged 31 to 39 years. Within the pediatric cohort, there was no significant difference in overall survival (OS) between low- and high-risk groups (5-year OS, 100% vs 98.5%; P = .29). In contrast, within the young adult cohorts, there was a significant difference in OS between low- and high-risk groups in patients aged 22 to 30 years (5-year OS, 100% vs 96.1%; P = .01) and 31 to 39 years (5-year OS, 100% vs 88.5%; P < .001). When high-risk patients were matched 1:1 on high-risk criteria and race, pediatric patients were associated with better OS than those aged 22 to 30 years (P = .044) and those aged 31 to 39 years (P = .005).

CONCLUSION

Children have excellent OS, irrespective of adult-derived high-risk status. These findings underscore the need to understand how age modifies clinicopathologic risk factors.

Salivary gland carcinoma in children and adolescents: The EXPeRT/PARTNER diagnosis and treatment recommendations

Salivary gland carcinomas (SGCs) are rare during childhood and adolescence. Consequently, no standardized recommendations for the diagnosis and therapeutic management of pediatric SGC are available, and pediatric oncologists and surgeons generally follow adult guidelines. Complete surgical resection with adequate margins constitutes the cornerstone of treatment. However, the indications and modalities of adjuvant therapy remain controversial and may be challenging in view of the potential long-term toxicities in the pediatric population. This paper presents the consensus recommendations for the diagnosis and treatment of children and adolescents with SGCs, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the EU-funded PARTNER project (Paediatric Rare Tumours Network - European Registry).

Clinicopathological analysis and survival outcomes of primary salivary gland tumors in pediatric patients: A systematic review

BACKGROUND

Salivary gland tumors are a diverse group of uncommon neoplasms that are rare in pediatric patients. The aim of this study was to evaluate the clinicopathological profile and survival outcomes of pediatric patients affected by salivary gland tumors.

MATERIALS AND METHODS

An extensive search was carried out using the MEDLINE/PubMed, EMBASE, Scopus databases, and grey literature. The risk of bias was available in all papers included.

RESULTS

A total of 2,830 articles were initially retrieved with 54 remaining for data extraction, resulting in 2,937 cases. This comprised forty-five case series' and nine cohort studies. These tumors were slightly more prevalent in females (57.4%). The patients' age ranged from 0.3 to 19 years old, with a mean age of 13.3 years. Parotid was the most affected site (81.9%), and 99.2% of cases clinically exhibited a swelling. Presence of pain/tenderness was reported in 13.5% of the cases, with an average duration of 12.6 months for the appearance of symptoms. Most of the reported cases were malignant tumors (75.4%), with mucoepidermoid carcinoma the most common tumor of all tumors (44.8%), followed by pleomorphic adenoma (24.1%). Surgery alone was the leading treatment choice in 74.9% cases, and the 5-year overall survival rate of patients was 93.1%. Patients with symptoms (P = .001), local recurrence (P < .001), metastasis (P < .001), and those not undergoing surgery or surgery combined with radiotherapy (P < .001) showed lower survival rates.

CONCLUSION

The pediatric patients present a high frequency of malignant salivary neoplasms and a high overall survival rate.

Diagnosis and management of pediatric epithelial salivary gland malignancy

PURPOSE OF REVIEW

Salivary tumors are uncommon among children but are more likely to be malignant compared with adults. A lack of experience makes consensus in treatment elusive. Amidst recent publication of large institutional and national series, this review aims to discuss the epidemiology, diagnosis, investigation, and treatment for pediatric epithelial salivary malignancies.

RECENT FINDINGS

Pediatric salivary malignancies are often low grade and carry a favorable prognosis. High-grade tumors portend an increased risk of recurrence and a decreased survival. Surgeons should strive for oncologic resection with clear margins and avoid enucleation and excisional biopsies. Overt nodal metastases require concurrent neck dissection, whereas elective neck dissections may be reserved for cases with high risk of occult disease, such as advanced stage and high-grade neoplasms. Adjuvant radiation should be considered in high-grade tumors.

SUMMARY

The paucity of high-level evidence clouds treatment decisions and further encourages pediatric salivary malignancies to be treated in an experienced center with a multidisciplinary approach.

Differentiation malignant from benign parotid tumors in children with diffusion-weighted MR imaging

PURPOSE

To differentiate pediatric solid malignant from the benign parotid tumors with diffusion-weighted MR imaging (DWI).

MATERIALS AND METHODS

A retrospective study comprising 38 children with parotid tumors (21 boys and 17 girls aged from 2 months to 17 years) was conducted using (DWI) of the parotid gland. Apparent diffusion coefficient (ADC) maps were generated. The ADC value of the parotid tumors was calculated.

RESULTS

The mean ADC value of malignant parotid tumors (1.08 ± 0.1, 1.04 ± 0.1 × 10^-3mm²/s) was significantly lower [P = 0.001] than that of benign lesions (1.69 ± 0.2, 1.72 ± 0.3 × 10^-3mm²/s). A threshold of ADC of 1.40, 1.33 × 10^-3mm²/s was used for differentiating malignant parotid tumors from benign lesions and led to the best results of the area under the curve of 0.940, 0.929, accuracy of 86, 89%, sensitivity of 94, 94%, specificity of 80, 85%, negative predictive value of 94.1, 94.4%, and positive predictive value of 81, 85%. There was insignificant difference in ADC values of malignant lesions (P = 0.23, 0.30) as well as within benign lesions (P = 0.25, 0.08).

CONCLUSION

DWI is an innovative anticipating imaging technique that can be used in the differentiation of pediatric solid malignant parotid tumors from benign lesions.

Efficacy of surgery combined with postoperative 125 I interstitial brachytherapy for treatment of acinic cell carcinoma of the parotid gland in children and adolescents

BACKGROUND

Acinic cell carcinoma (AciCC) is rare in children; therefore, reaching a consensus on its management is challenging and radiotherapy is limited by concerns about long-term toxicity. The purpose of this study is to analyze the effectiveness and safety of surgery plus postoperative ¹²⁵ I interstitial brachytherapy (IBT) for children and adolescents with AciCC of the parotid gland (PG) treated at a single institution.

PROCEDURE

Sixteen patients ≤ 18 years old with AciCC of the PG treated with surgery plus ¹²⁵ I IBT from 2007 to 2018 were included. Surgery was the primary treatment; ten patients underwent total gross excision and six subtotal gross excision. The matched peripheral dose was 60-120 Gy. Overall survival, disease-free survival (DFS), local control rate, distant metastasis, and radiation-associated toxicities were analyzed, and factors influencing outcomes were evaluated.

RESULTS

During follow-up (1.8-12.6 years; mean, 6.3 years), lymph node metastasis was observed in one case, 2.6 years after ¹²⁵ I IBT treatment. The five-year overall and DFS rates were 100% and 91.7%, respectively. On univariate analysis, tumor size ≥ 3 cm (100% vs 50%; P = 0.025) and extraglandular extension (100% vs 50%; P = 0.025) were significant prognostic indicators for DFS. No severe radiation-associated complications occurred.

CONCLUSIONS

Children and adolescents with AciCC of the PG with high-risk features can be managed using surgery plus postoperative ¹²⁵ I IBT with excellent local control. Radiation-related complications were minor. Patients with facial nerve involvement can have their facial nerves preserved. Residual tumors can be safely managed using adjuvant ¹²⁵ I IBT.

Significance of Pretreatment Neutrophil-to-Lymphocyte Ratio in Mucoepidermoid Carcinoma of Pediatrics: A Multicenter Study

Background: Our goal was to analyze the value of the pretreatment neutrophil-to-lymphocyte ratio (NLR) in the prognosis of pediatrics with parotid mucoepidermoid carcinoma (MEC). Methods: Patients (≤ 18 years old) undergoing surgical treatment for primary parotid MEC were enrolled from multiple clinical centers retrospectively. The χ²-test was used to analyze the associations between clinicopathological variables and the NLR. The main study endpoints were recurrence-free survival (RFS) and disease-specific survival (DSS). The prognostic value of NLR was assessed by Kaplan-Meier method and Cox model analysis. Results: There were 88 patients included in total, with mean NLR of 2.32 (range, 1.8-6.0). Histologic tumor grade and tumor stage were associated with the NLR significantly. The 10-year RFS rates were 98 and 81% for patients with an NLR < 2.32 and patients with an NLR ≥ 2.32, respectively, the difference was significant (p = 0.010). The 10-year DSS rate was 97 and 81% for patients with an NLR < 2.32 and patients with an NLR ≥ 2.32, respectively; the difference was not significant (p = 0.072). The independence of NLR in predicting the RFS was further confirmed in Cox model analysis. Conclusion: The NLR significantly affects the prognosis in pediatrics with primary parotid MEC.

Oncologic outcome of parotid mucoepidermoid carcinoma in pediatric patients

Background

The goal of this study was to investigate the long-term oncologic outcome of parotid mucoepidermoid carcinoma (MEC) in pediatric patients.

Patients and methods

Patients <19 years old who were diagnosed with MEC from January 1990 to December 2017 were retrospectively enrolled in this study. The main analyzed indexes included intraparotid node (IPN) metastasis, neutrophil-tolymphocyte ratio (NLR), loco-regional control (LRC), and disease-specific survival (DSS) rates.

Results

A total of 73 patients were enrolled. IPN metastasis occurred in 13 (17.8%) patients; the mean value of the NLR was 2.48 (range: 1.3–6.1). Loco-regional recurrence occurred in 12 patients, and 7 patients died of the disease. The 10-year LRC and DSS rates were 83% and 88%, respectively. IPN metastasis remained significantly related to recurrence in both univariate and Cox model analyses; a high NLR was significantly associated with recurrence in the univariate analysis but not in the Cox model. IPN metastasis remained significantly related to disease-related death in both the univariate and Cox model analyses; a high NLR was not associated with the DSS in univariate analysis.

Conclusion

The long-term survival rate was relatively favorable in pediatric MEC. IPN metastasis was an independent risk factor for loco-regional recurrence and DSS. The role of the NLR in predicting survival in parotid cancer requires more research.