Pediatric epithelial salivary gland tumors: spectrum of histologies and cytogenetics at a children's hospital

Is Milan for kids?: The Milan System for Reporting Salivary Gland Cytology in pediatric patients at an academic children's hospital with cytologic-histologic correlation

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) provides a useful framework for the diagnosis of salivary gland fine-needle aspiration (FNA) biopsies. In this study, the MSRSGC was applied to salivary gland FNAs in pediatric patients to assess its usefulness and look at pitfalls.

METHODS

The laboratory information system was queried over a 15-year period for all salivary gland FNAs in patients 18 years old or younger. Patient demographics, FNA diagnosis categorized according to the MSRSGC, and follow-up surgical pathology diagnoses were examined and correlated.

RESULTS

Thirty-two cases were identified, with an average age of 12 years (range, 0.6-18 years). A majority of the cases (84.4%) were from the parotid region. Twenty of 32 cases (62.5%) had follow-up resection. MSRSGC recategorization diagnoses of the 32 FNA cases were 34% benign neoplasm, 31% nonneoplastic, 16% nondiagnostic, 9% atypia of undetermined significance, 3% salivary neoplasm of uncertain malignant potential, 3% suspicious for malignancy, and 3% malignant. Overall, the sensitivity and specificity were 100% and 80%, respectively. On follow-up resection, 55% were neoplastic: pleomorphic adenomas (n = 6; 55%), pilomatricoma (n = 3; 28%), mucoepidermoid carcinoma (n = 1; 9%), schwannoma (n = 1; 9%), and myofibroma (n = 1; 9%).

CONCLUSIONS

The MSRSGC performed fairly well in the pediatric population with a low overall risk of malignancy (6%) and high sensitivity. Although the majority of pediatric salivary gland FNAs were benign, 55% of resected cases were positive for a neoplasm, with benign neoplasms outnumbering malignancy. Challenging entities included inflammatory conditions, like immunoglobulin G4-related sialadenitis, and skin and soft tissue lesions near the salivary gland.

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.

Molecular cytogenetic pilot study on pleomorphic adenomas of salivary glands

Pleomorphic adenomas (PAs) of salivary glands are the most frequent entity of solid parotid tumors. Nonetheless, their genetics is not yet well understood. Thus, the current study characterized 14 PAs using a unique combination of cytogenetic, molecular cytogenetic and/or molecular karyotyping based approaches. The current study applied G-banding based on trypsin treatment and Giemsa-staining in peripheral blood and tumor tissue. Additionally, fluorescence in situ hybridization was performed using whole chromosome painting or centromeric probes. Array-based comparative genomic hybridization was also conducted. In 5 of 14 cases, chromosomal and/or submicroscopic alterations were characterized. Balanced and unbalanced translocations, loss or gain of whole chromosomes and submicroscopic copy number alterations were detected. Furthermore, the first case of a so-called ‘jumping translocation’ in a PA was reported. The genes twist-related protein 1 and distal-less homeobox 5 were also involved in copy number variations in two PAs. In conclusion, approaches utilized in the current study are highly suited to characterize the genetic constitution of PAs.

Salivary gland epithelial neoplasms in pediatric population: a single-institute experience with a focus on the histologic spectrum and clinical outcome

Salivary gland epithelial neoplasms are rare in children and adolescents, with only a handful of large series having been published. A retrospective study was conducted for 57 cases in patients 20 years or younger. The tumors were located in the parotid (n=36), submandibular gland (n=7), and minor salivary glands (n=14). Nineteen (33%) tumors were pleomorphic adenoma, whereas the remaining (67%) were malignant. The histologic types of carcinomas were mucoepidermoid carcinoma (MEC, n=19, 33%), acinic cell carcinoma (n=7, 12%), adenoid cystic carcinoma (n=6, 11%), secretory carcinoma (mammary analogue) (SC, n=4, 7%), and myoepithelial carcinoma (n=2, 4%). Ninety-three percent (13/14) of the minor and 58% (25/43) of the major salivary gland tumors were malignant. A 7-year-old girl (2%) with a high-grade MEC died from her disease because of uncontrollable locoregional recurrence. Seven patients (16%) developed recurrence including 2 distant metastases from adenoid cystic carcinoma and 6 locoregional recurrences (2 pleomorphic adenomas, 1 SC, 1 myoepithelial carcinoma, 1 adenoid cystic carcinoma, and 1 MEC). The following parameters were associated with decreased disease-free survival in malignant tumors: elevated mitotic index of >4/10 high-power fields (log-rank test, P<.001), and advanced American Joint Committee on Cancer pT (P=.029) and pN stage (P<.001). In conclusion, myoepithelial carcinoma and SC can occur in the pediatric population and should be considered in the differential diagnosis. Salivary gland malignancies in children appear to have better clinical outcome, associated with a 10-year recurrence-free survival rate of 74% and a 10-year disease-specific survival of 94%.

Mucoepidermoid carcinoma of the parotid as a secondary malignancy after chemotherapy in a child with neuroblastoma

Secondary neoplasms are not reported frequently after neuroblastoma, which until recently was a cancer with limited long-term survival. Although salivary gland tumors in children and adolescents may be idiopathic, they are seen more often after head and neck radiation. We report a child with stage 4 neuroblastoma treated with high-dose multiagent chemotherapy without radiation therapy to his neck who, within 1 year of treatment, developed a low-grade but large and locally aggressive mucoepidermoid carcinoma of his parotid gland further characterized by a t(11;19)(q21;p13.1). Our patient extends the spectrum of secondary neoplasms after neuroblastoma.

Pleomorphic adenoma of the salivary glands in children and adolescents

BACKGROUND

Pleomorphic adenomas (PAs) of the salivary glands are rare in children and adolescents. We reviewed the clinical manifestations, pathologic features, treatment, and prognosis of salivary gland PA in 90 children and adolescents.

METHODS

Clinical data including age, sex, location, symptoms, the period of evolution of the symptoms, pathologic type, and surgical treatment were evaluated.

RESULTS

The median age was 16.5 years old. There was a 1.43:1 female-to-male ratio. The parotid gland was the most commonly affected major gland (56.7%), and the palate, the most common site of minor salivary gland involvement. Ultrasonography and computed tomography were performed in most cases for diagnosis. Superficial parotidectomy or total parotidectomy with facial nerve dissection and preservation was the most common surgical procedure. Submandibular triangle dissection was applied to all submandibular PAs. Classic-type PA was the most common histologic subtype (43.3%).

CONCLUSIONS

Salivary gland PAs in children and adolescents have different characteristics compared with their adult counterparts in regard to histologic subtype and location. Surgical removal is the best treatment option for PAs in children and adolescents.