Salivary gland carcinoma in Denmark: a national update and follow-up on incidence, histology, and outcome

Molecular Aspects of Mucoepidermoid Carcinoma and Adenoid Cystic Carcinoma of the Salivary Gland

BACKGROUND

Salivary gland tumors (SGTs) are rare and highly heterogeneous lesions, making diagnosis a challenging activity. In addition, the small number of studies and samples evaluated difficults the determination of prognosis and diagnosis. Despite the solid advances achieved by research, there is still an intense need to investigate biomarkers for diagnosis, prognosis and that explain the evolution and progression of SGTs.

METHODS

We performed a comprehensive literature review of the molecular alterations focusing on the most frequent malignant SGTs: mucoepidermoid carcinoma and adenoid cystic carcinoma.

RESULTS

Due to the importance of biomarkers in the tumorigenenic process, this review aimed to address the mechanisms involved and to describe molecular and biomarker pathways to better understand some aspects of the pathophysiology of salivary gland tumorigenesis.

CONCLUSIONS

Molecular analysis is essential not only to improve the diagnosis and prognosis of the tumors but also to identify novel driver pathways in the precision medicine scenario.

The extent of androgen receptor and HER2 expression allows for targeted therapy in most cases of salivary duct carcinoma: analysis of clinical and histopathological data in a tertiary care center

PURPOSE

The incidence of salivary duct carcinoma (SDC) seems to be underestimated due to inaccurate classification. Further, the frequency of SDC patients with targeted therapy options according to current guidelines is unclear. Therefore, this study aimed at (a) describing the proportion of SDC among salivary gland carcinoma (SGC) before and after reclassification of cases initially classified as adenocarcinoma, not otherwise specified (ANOS); and (b) quantifying the frequency of SDC patients with targeted therapy options.

METHODS

All patients with SDC or ANOS treated in a tertiary care center between 1996 and 2023 were identified. Histopathological diagnosis was verified for patients primarily diagnosed with SDC and reviewed for patients initially diagnosed with ANOS. Clinical data for SDC patients were retrieved from clinical charts. Immunohistochemical (IHC) androgen receptor (AR) and HER2 staining was performed.

RESULTS

Among 46 SDC, 34 were primarily diagnosed as SDC and 12 had initially been classified as ANOS. The proportion of SDC among SGC was 12.1% and was rising when comparing the time periods 2000-2015 (7.1-11.5%) versus 2016-2023 (15.4-18.1%). Nuclear AR staining in > 70% of tumor cells was found in 56.8% and HER2 positivity (IHC 3 +) in 36.4% of cases. 70.5% of patients showed AR staining in > 70% of tumor cells and/or HER2 positivity and therefore at least one molecular target. 5-year overall and disease-free survival (DFS) were 62.8% and 41.0%. Multivariate Cox regression revealed positive resection margins (HR = 4.0, p = 0.03) as independent negative predictor for DFS.

CONCLUSIONS

The results suggest a rising SDC incidence and show that the extent of the AR and HER2 expression allows for targeted therapy in most SDC cases.

Expanding the cytological and architectural spectrum of mucoepidermoid carcinoma: The key to solving diagnostic problems in morphological variants

Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumor. Varying sized cysts and sheets composed of three cell types (epidermoid, intermediate, and mucous cells) with varying degrees of atypia form the characteristic histological appearance of MEC. MEC frequently contains a wide variety of modified tumor cells and can be entirely cystic or completely solid. Under these circumstances, MEC requires critical differentiation from many mimickers, ranging from simple cysts and benign tumors to high-grade carcinomas. Tumor-associated lymphoid proliferation and sclerotic changes in the stroma also contribute to diagnostic difficulties. Several well-known diagnostically challenging variants (oncocytic, clear cell, spindle cell, and sclerosing) exist in MEC. With the advent of studies on specific CRTC1/3::MAML2 fusion genes in MEC, newly proposed subtypes have emerged, including Warthin-like and non-sebaceous lymphadenoma-like MECs. In addition to the recently defined mucoacinar variant with a serous cell phenotype, MEC devoid of squamous differentiation has also been reported, implying the need to reconsider this basic concept. In this article, we outline the general clinical features and MAML2 status of conventional MEC and review the cytoarchitectural subtypes, with an emphasis on a pitfall in the interpretation of this histologically diverse single entity.

Prognostic and predictive biomarkers in head and neck cancer: something old, something new, something borrowed, something blue and a sixpence in your shoe

A biomarker is a measurable indicator of biological or pathological processes or the response to an exposure or intervention and is used to guide management decisions. In head and neck pathology, biomarkers are assessed by histological criteria and immunohistochemical and molecular studies. Surgical resection remains the mainstay of management of many head and neck malignancies. Adjuvant radiotherapy and/or systemic therapy may be administered depending on the presence of adverse prognostic factors identified on histopathological or immunohistochemical examination. In this review, we outline the clinically relevant prognostic and predictive factors in head and neck malignancies including conventionally recognised factors such as tumour size, depth of invasion, lymphovascular and perineural invasion and margin status as well as novel evolving factors such as recurrent genetic rearrangements and assessment of immune checkpoints. Practical issues are discussed to assist with recognising and reporting of these factors. A summary of useful tools such as structured pathology report formats is also included to assist with comprehensive reporting of all clinically relevant parameters, minimise risk and improve workflow efficiencies.

Prognostic effects of previous cancer history on patients with major salivary gland cancer

OBJECTIVES

To explore the prognostic effects of previous cancer history on patients with major salivary gland cancer (SGC).

SUBJECTS AND METHODS

SGC patients with (sec-SGC) and without (one-SGC) a previous cancer from the SEER database were identified. Cox proportional hazards regression (CoxPH) models were used to compare the prognosis between sec-SGC and one-SGC patients. Subgroup analyses for sec-SGC patients by gender, previous cancer types, previous cancer histology, and cancer diagnosis interval (CDI) were performed. Two CoxPH models were constructed to distinguish sec-SGC patients with different prognostic risks.

RESULTS

9098 SGC patients were enrolled. Overall, sec-SGC patients (adjusted HR [aHR] = 1.26, p < 0.001), especially those with a CDI ≤ 5 years (aHR = 1.47, p < 0.001), had worse overall survival (OS) than one-SGC patients. In subgroup analysis, only sec-SGC patients with a previous head and neck cancer who were female (aHR = 2.38, p = 0.005), with a CDI ≤ 5 years (aHR = 1.65, p = 0.007) or with a previous squamous cell carcinoma (aHR = 6.52, p < 0.001) had worse OS. Our models successfully differentiated all sec-SGC patients into high-, intermediate- and low-risk groups with different prognosis.

CONCLUSIONS

Sec-SGC patients with different previous cancer types, gender, CDI and previous cancer histology had varied prognosis. The models we constructed could help differentiate the prognosis of sec-SGC patients with different risks.

Post-operative radiotherapy in adenoid cystic carcinoma of salivary glands versus surgery alone: what is the evidence about survival and local control? A systematic review and meta-analysis

BACKGROUND

Adenoid cystic carcinoma of the salivary glands is a relatively rare malignancy characterized by slow growth and a poor prognosis, and effective treatments remain challenging to identify. This systematic review, following the PRISMA guidelines, aimed to analyze the potential benefits of post-operative radiotherapy in terms of local control of recurrences and survival advantages when compared with surgery alone in patients with adenoid cystic carcinoma.

METHODS

A comprehensive systematic review was conducted by searching the MEDLINE, Cochrane, EMBASE, and OVID databases from January 1999 to July 2022. The goal was to identify articles comparing surgery alone with surgery plus postoperative radiotherapy for adenoid cystic carcinoma of the salivary glands. Downs and Black Checklist was used to assess the methodological quality and risk of bias of each included study. The data analysis was performed using Review Manager version 5.4.1.

RESULTS

This review included 8 studies comprising a total of 3103 patients, divided based on the analyzed outcomes. The pooled odds ratio for overall survival at 5 years was 0.87 (95% confidence interval 0.43-1.76, p = 0.70), and at 10 years was 1.23 (95% confidence interval 0.69-2.16, p = 0.48). In both cases, no statistically significant differences were observed. However, the pooled odds ratio for local control at 5 years was 3.37 (95% confidence interval 1.35-8.42, p = 0.009), providing strong support for the use of post-operative radiation.

CONCLUSIONS

The findings from the meta-analysis suggest that post-operative radiotherapy significantly improves local control in patients with adenoid cystic carcinoma. However, there was no statistically significant increase in survival at 5 and 10 years. It is essential to note that the quality of the studies included in this meta-analysis ranged from fair to poor. To better clarify the indications for post-operative radiotherapy, future high-quality research is needed, particularly with improved stratification of patient groups. Additionally, it is important to recognize that achieving local control in adenoid cystic carcinoma is crucial for enhancing the overall quality of life for patients. We acknowledge that this review was not registered in the PROSPERO database, and the data pooling was conducted using a random effects model.

Evaluation of the efficacy of adjuvant radiotherapy versus chemoradiotherapy in patients with salivary gland tumors

AIMS

The aim of this study was to compare the efficacy of adjuvant radiotherapy (RT) versus adjuvant chemoradiotherapy (CRT) in patients with salivary gland tumors (SGTs).

MATERIALS AND METHODS

Data from patients who underwent adjuvant RT for a diagnosis of SG cancer at Ankara Atatürk Education and Research Hospital, Ankara Numune Education and Research Hospital and Ankara Bilkent City Hospital between September 01, 2009 and September 01, 2022 were analysed retrospectively. We evaluated the efficacy of RT alone versus CRT in these patients in terms of acute response, treatment tolerance, overall survival (OS), and disease-free survival (DFS).

RESULTS

Fifty-five patients who underwent RT between September 14, 2009 and August 04, 2022 at Ankara Atatürk Education and Research Hospital, Ankara Numune Education and Research Hospital and Ankara Bilkent City Hospital were included in this study. Eight patients who did not meet the study criteria were excluded; thus, the analysis was performed for 47 patients. The median follow-up period was 60 months (range: 6-160 months). The median patient age was 53 years (range: 18-86 years). Thirty-nine patients (83%) had parotid tumors and eight patients (17%) had submandibular cancer. The time from surgery to RT was 48 days (range: 20-126 days). Intensity-modulated radiotherapy was administered to all patients and the median RT dose was 66 Gy (range: 52-70 Gy). Concomitant chemotherapy (CCT) (40 mg/m2 of cisplatin weekly) was administered to 13 patients (27.7%). Acute adverse events were observed in 17 patients (36.2%). Interruption of RT was noted for only six patients (12.8%), and this proportion did not differ significantly between the CRT and RT-only arms (P = 0.538). Acute side effects were observed in 17 patients (36.2%), and there were no significant relationships between acute side effects and the administration of CCT (P = 0.112). Recurrence was observed in 10 patients (21.3%). All recurrences were locoregional and no distant metastases were observed during the follow-up period. The median DFS of the patients was 48 months (range: 4-160 months), 1-year DFS was 86%, 2-year DFS was 83.5%, and 5-year DFS was 77.9%. There was no statistically significant difference in DFS between the adjuvant CRT and RT-alone arms (P = 0.114). At the date of last follow-up, 14 patients (29.8%) had died. The median OS of the patients was 58.5 months (range: 6-160 months), 1-year OS was 91.4%, 2-year OS was 86.8%, and 5-year OS was 78%. There was no statistically significant difference in OS between the adjuvant CRT and RT-only arms (P = 0.453).

CONCLUSION

Stage was identified as the most important prognostic factor for DFS and OS. No significant differences in OS, DFS, or acute side effects were observed between the CRT and RT-only arms. Additional studies are needed to identify the subgroup of SGT patients for which CRT is most warranted.

Adenoid cystic carcinoma metastatic to the kidney: a series of 10 patients emphasizing unilateral presentation and long time interval from primary diagnosis

Adenoid cystic carcinoma (AdCC) metastasis to kidney is rare. We identified 10 patients with metastatic AdCC in multi-institutional collaboration. Core needle biopsy was the most common specimen (n = 6). Patients were predominately female (n = 7) with a median age of 48 years (35-62 years). The most common primary location of the AdCC was head and neck (n = 6, among them parotid gland = 4), followed by lung (n = 2), breast (n = 1), and vulva (n = 1). Median lapse between primary AdCC and renal metastasis was almost 13 years (154 months, range 1-336 months). Moreover, all but one patient had unilateral kidney metastasis. The majority of metastatic AdCC within the kidney demonstrated mixed growth patterns, frequently cribriform, and tubular morphology. Follow-up available for 8 patients showed 6 alive with disease and 2 died of disease (the longest survival was 4 years past the diagnosis of renal metastasis). A systematic literature review including 29 patients revealed that kidney metastasis by AdCC is usually a late event, is typically unilateral, and is usually composed of one to three foci, and thus has clinical features which mimic a primary renal tumor.

The characteristics of Polish patients with salivary gland tumors: a ten-year single-center experience

OBJECTIVES

The study aims to provide insights into the characteristics of Polish patients with different salivary gland pathologies.

MATERIALS AND METHODS

This is a retrospective study conducted at a single center, including patients who underwent surgery for salivary gland pathologies between 2012 and 2022.

RESULTS

This study included 239 patients who underwent surgery for salivary gland tumors or inflammatory diseases. Malignant tumors were diagnosed in 9.8% of participants, while 64% had benign tumors and 21% suffered from inflammation. The occurrence of complications after surgery was relatively low, with 9.9% of participants experiencing slight facial weakness or mild dysfunction, and 3% experiencing complete paralysis of the facial nerves. Significant differences were observed between patients with cancers and those with benign tumors and inflammation in terms of age. Cancers were more common in females (67% vs. 33%) and predominantly localized in the parotid glands (95%).

CONCLUSION

Benign tumors, such as Warthin's tumors and polymorphous adenoma, were predominantly found in the parotid glands of patients aged 39-72 years. On the other hand, inflammatory diseases were primarily localized within the submandibular glands of males aged 40-68 years. Additionally, the presence of a malignant tumor was associated with longer hospitalization periods related to surgery and a higher risk of severe complications.

CLINICAL RELEVANCE

This study on Polish patients with salivary gland tumors provides valuable clinical insights that can aid in diagnosis, treatment planning, patient counseling, and further research in the field of oncology. It contributes to the overall understanding of salivary gland tumors, potentially benefiting both patients and healthcare providers.

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.

Diagnosis of Adenoid Cystic Carcinoma with Striking Tubular Hypereosinophilia by MYB and EWSR1 Breakapart Fluorescence In Situ Hybridization

BACKGROUND

Adenoid cystic carcinoma (AdCC), associated with MYB/MYBL1 gene rearrangements, shows epithelial and basaloid myoepithelial cells arranged in tubular, cribriform and solid patterns. Variations from this classic morphology make diagnosis challenging, necessitating molecular testing. AdCC with striking tubular hypereosinophilia (AdCC-STE) is one such recently described histological subtype.

METHODS

A 52-year-old female presented with a floor of mouth swelling for two months, diagnosed elsewhere as polymorphous adenocarcinoma (PAC). A biopsy was obtained. With a diagnosis of oncocytic neoplasm, wide excision of the tumor was undertaken. Histological examination, fluorescence in situ hybridization (FISH) and ultrastructural examination were performed. Archival cases of PAC and epithelial myoepithelial carcinoma (EMC) were reviewed, and MYB immunostaining and FISH were performed to identify potential AdCC-STE cases.

RESULTS

The excised tumor from the index patient showed bilayered tubules, micropapillae and cribriform pattern. Luminal cells with hypereosinophilic to clear cytoplasm were surrounded by flattened abluminal cells. Focally, basophilic matrix was seen within sharply demarcated pseudocystic spaces. FISH revealed MYB and EWSR1 gene rearrangements, confirmatory of AdCC-STE. Electron microscopy showed features consistent with AdCC; however, mitochondria were not prominent. Among 14 archival PACs, two showed MYB immunopositivity; one showed MYB rearrangement but was classical AdCC. Among 35 EMC, one case showed MYB immunoreactivity and eosinophilia of luminal cells but lacked MYB/MYBL1 rearrangement.

CONCLUSION

Awareness of unusual histological subtypes of AdCC, such as AdCC-STE, is imperative, as it may be misdiagnosed as PAC and EMC, among others. Presence of basophilic matrix and squamoid morules in a biphasic tumor even with hypereosinophilic rather than basaloid myoepithelial appearance should raise suspicion for AdCC-STE, and prompt molecular testing for confirmation. With wider accessibility, lower cost and significantly shorter turn-around-time when compared to RNA sequencing, FISH can be employed for confirmation of diagnosis, especially in low- and middle-income countries.

A novel postoperative nomogram and risk classification system for individualized estimation of survival among patients with parotid gland carcinoma after surgery

BACKGROUND

Parotid gland carcinoma (PGC) is a rare but aggressive head and neck cancer, and the prognostic model associated with survival after surgical resection has not yet been established. This study aimed to construct a novel postoperative nomogram and risk classification system for the individualized prediction of overall survival (OS) among patients with resected PGC.

METHODS

Patients with PGC who underwent surgery between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database were randomized into training and validation cohorts (7:3). A nomogram developed using independent prognostic factors based on the results of the multivariate Cox regression analysis. Harrell's concordance index (C-index), time-dependent area under the curve (AUC), and calibration plots were used to validate the performance of the nomogram. Moreover, decision curve analysis (DCA) was performed to compare the clinical use of the nomogram with that of traditional TNM staging.

RESULTS

In this study, 5077 patients who underwent surgery for PGC were included. Age, sex, marital status, tumor grade, histology, TNM stage, surgery type, radiotherapy, and chemotherapy were independent prognostic factors. Based on these independent factors, a postoperative nomogram was developed. The C-index of the proposed nomogram was 0.807 (95% confidence interval 0.797-0.817). Meanwhile, the time-dependent AUC (> 0.8) indicated that the nomogram had a satisfactory discriminative ability. The calibration curves showed good concordance between the predicted and actual probabilities of OS, and DCA curves indicated that the nomogram had a better clinical application value than the traditional TNM staging. Moreover, a risk classification system was built that could perfectly classify patients with PGC into three risk groups.

CONCLUSIONS

This study constructed a novel postoperative nomogram and corresponding risk classification system to predict the OS of patients with PGC after surgery. These tools can be used to stratify patients with high or low risk of mortality and provide high-risk patients with more directed therapies and closer follow-up.

Epidemiology of and factors associated with overall survival for patients with head and neck adenoid cystic carcinoma

BACKGROUND

Updated epidemiologic and survival data of head and neck adenoid cystic carcinoma (HNACC) are lacking. This retrospective study aimed to clarify the incidence, prevalence, and overall survival (OS) of patients with HNACC and establish relevant nomogram.

METHODS

Trends in incidence, limited-duration prevalence, and relative survival (RS) rates were evaluated using data from the Surveillance, Epidemiology, and End Results (SEER) database, and annual percent change (APC) in rates was calculated using joinpoint regression. Data on age, sex, site, stage, and surgery were used in construction and validation of the nomogram.

RESULTS

The study included 6474 patients; 57.7% were female and 78.6% were white. The age-adjusted incidence rates of HNACC decreased significantly from 0.41 to 0.25 per 100,000 [1975-2018; average annual percent change (AAPC): - 1.37, P < 0.001], which was dominated by the localized stage. The 20-year limited duration prevalence increased from 0.00028% to 0.00262%. The 5- and 10-year RS rates of all HNACC patients were 80.0% and 65.5%, respectively. RS rates in HNACC showed a slight increase over time, with APC values of 0.03 for 5-year (P < 0.05) and 0.13 for 10-year (P < 0.05) RS. A prognostic model was constructed. The C-indices for the training and testing sets were both 0.734. The nomogram's discrimination efficiency was evaluated using the receiver operating characteristic curve and had moderate predictive power.

CONCLUSIONS

Over the past 40 years, the incidence of HNACC decreased accompanied by slightly improved survival rates. Nomogram was capable of predicting the 5- and 10-year OS rates with moderate accuracy.

Prognostic factors in surgically treated malignant salivary gland tumors

OBJECTIVES

To identify prognostic factors for evidence-based risk stratification in malignant salivary gland tumors.

METHODS

This retrospective study identified 162 patients who presented with malignant salivary gland tumors between 2010 and 2020. Final analysis included 91 patients who underwent surgical treatment at our institution and were followed-up for ≥ 1 year. Medical records were reviewed and patients were categorized according to their risk profile.

RESULTS

This study included 91 patients (51 males, 40 females, mean age 61 years). The most frequent entities were adenoid cystic carcinoma (n = 13, 14.3%) and mucoepidermoid carcinoma (n = 12, 13.2%). Kaplan-Meier analysis demonstrated a five-year overall survival (OS) of 66.2% and a recurrence-free survival (RFS) of 50.5%. Age > 60 years (p = 0.011), categorization into high-risk group (p = 0.011), UICC stage (p = 0.020), T stage (p = 0.032), grading (p = 0.045) and vascular invasion (p < 0.001) were significantly associated with OS; age > 60 years (p = 0.014), categorization into high-risk group (p < 0.001), UICC stage (p = 0.021), T stage (p = 0.017), grading (p = 0.011), vascular invasion (p = 0.012) and lymphovascular invasion (p < 0.001) were significantly associated with RFS. Multivariate Cox regression with backward elimination identified T stage (HR 1.835; 95% CI 1.187-2.836; p = 0.006) and grading (HR 2.233; 95% CI 1.113-4.480; p = 0.024) as significant factors for OS. Grading (HR 2.499; 95% CI 1.344-4.648; p = 0.004) was confirmed as a significant factor for RFS.

CONCLUSION

Considering the risk of recurrence and distant metastasis in malignant salivary gland tumors, locoregional surgical control may not be sufficient and adjuvant therapies such as radiotherapy and/or systemic therapies should be considered.

Epidemiology, outcomes, and prognostic factors in submandibular gland carcinomas: a national DAHANCA study

PURPOSE

The aim of this study is to present incidence, histological subtypes, survival rates, and prognostic factors based on a national cohort of patients with salivary gland carcinoma.

METHODS

All Danish patients with submandibular gland carcinoma diagnosed from 1990 to 2015 (n = 206) were included and analyzed following histological re-evaluation. Data were collected by the Danish Head and Neck Cancer Group (DAHANCA). Overall, disease-specific and recurrence-free survival were evaluated. Prognostic factors were analyzed with multivariate Cox Hazard Regression.

RESULTS

The study population consisted of 109 (53%) men and 97 (47%) women, median age 62 years (range 11-102). Adenoid cystic carcinoma was the most frequent subtype (50%). Tumour classification T1/T2 (75%) and N0 (78%) was most frequent. The mean crude incidence was 0.17/100,000/year. Most patients (n = 194, 94%) were treated with primary surgery, and 130 (67%) received postoperative radiotherapy. The 5- and 10-year survival rates were for overall survival 64% and 41%, disease-specific survival 74% and 61%, and recurrence-free survival 70% and 56%, respectively. Survival rates were higher for adenoid cystic carcinoma compared to other subtypes, but the difference was not significant in multivariate analysis. Recurrence occurred in 69 patients, and 37 (53.6%) of them had recurrence in a distant site. Advanced T-classification and regional lymph-node metastases had significant negative impact on survival rates.

CONCLUSION

The incidence of submandibular gland carcinoma in Denmark was 0.17/100,000/year and stable during the time period. The most frequent subtype was adenoid cystic carcinoma. Half of the recurrences presented in a distant site, and multivariate analysis confirmed that advanced stage was independent negative prognostic factor for recurrence and survival.

Incidence and clinical outcome of primary carcinomas of the major salivary glands: 10-year data from a population-based state cancer registry in Germany

PURPOSE

The aim of this project was to provide an overview of the epidemiology of primary salivary gland carcinomas (SGC) in terms of incidence, distribution of clinicopathological features and survival in one of the largest cancer registries in Europe.

METHODS

Data were collected from patients with SGC of the major salivary glands registered in the population-based state cancer registry (Landeskrebsregister LKR) in North Rhine-Westphalia (NRW), Germany from 01/01/2009 to 12/31/2018. Age standardization of incidence was performed and relative survival estimates were computed by sex, histological group, age group and T-, N-, and M-stage.

RESULTS

A total of 1680 patients were included in this analysis. The most frequent tumor localization was the parotid gland (78%). Adenocarcinoma (not otherwise specified) was the most common tumor entity (18.5%). Most tumors were found in stages T1-T3 (29% T1; 29% T2; 28% T3). The age-standardized incidence rate (ASR) for SGC was 0.65/100,000 and remained stable during the observation period. There was an age-dependent incidence increasing especially from the age 70 years and onwards. The overall 5-year relative survival (RS) for all patients with SGC was 69.2%. RS was 80-95.6% for T1-2 stage tumors, 60.3% for T3, 47.3% for T4 stage, 87.4% for N0 and 51.2% for N1-2, 74.4% for M0 and 44.9% for M1.

CONCLUSION

Age-standardized incidence for SGC has been stable for the observed 10-year period. Smaller tumors and those without lymph node or distant metastases had a better RS than more advanced tumors.

Prognosis of adenoid cystic carcinoma in head and neck region treated with different regimens-A single-centre study

BACKGROUND

No study has evaluated the impact of regimen on recurrence, metastasis and survival in patients with adenoid cystic carcinoma (ACC). The present study aimed to compare the efficacy of radioactive seed implantation and other regimens in treating ACC, so as to investigate the clinical applicability of radioactive seed implantation and determine the indications for this regimen.

METHODS

A total of 188 patients with ACC in oromaxillofacial region were allocated to four groups according to the treatment regimen: group 1 was treated with a combination of surgery and ¹²⁵ I seed therapy, group 2 with a combination of surgery and external radiotherapy, group 3 with surgery, whereas group 4 was untreated. The Kaplan-Meier method was used to assess the survival rates, and the Cox regression analyses were used to identify the associated prognostic factors.

RESULTS

The overall survival rates of 188 patients and groups 1, 2, 3 and 4 were 85.7%, 75%, 68.2% and 37.5%, respectively. Cox regression analysis revealed that age, T stage, N stage and regimen were independent prognostic factors of survival. Amongst patients with primary ACC, the efficacy of radioactive seed implantation was higher in those with perineural invasion than in those without.

CONCLUSION

Patient age, T stage, N stage and regimen are independent prognostic factors of survival in patients with ACC. Patients treated with surgery combined with postoperative ¹²⁵ I seed radiotherapy have a higher overall survival rate, and those with perineural invasion are more suitable for radioactive seed implantation therapy.

Regression Derived Staging Model to Predict Overall and Disease Specific Survival in Patients With Major Salivary Gland Carcinomas With Independent External Validation

The current American Joint Cancer Committee (AJCC) staging system for salivary gland tumors does not include histology and grade in its classification despite their proven prognostic importance. We planned to analyze if a modified staging system integrating these two factors into the staging improves prognostic performance and then validate it externally.

Incorporation of tumor grade and histology in current AJCC staging results in better hazard discrimination.

Oncological outcomes of patients with salivary gland cancer treated with surgery and postoperative intensity-modulated radiotherapy: a retrospective cohort study

BACKGROUND

Salivary gland cancer (SGC) is relatively rare and constitutes a variety of histological subtypes. Previously published studies of SGC patients suggest that postoperative radiation using conventional radiotherapy (RT) or 3-dimensional (3D) conformal radiotherapy may have led to suboptimal oncological outcomes.

METHODS

We identified 60 patients with major SGC treated with surgery followed by postoperative intensity-modulated radiotherapy (IMRT). Data for overall survival (OS), progression-free survival (PFS), locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), prognostic factors, and treatment-related toxicities were analyzed. Survival was analyzed using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

With a median follow-up of 55.5 months, based on Kaplan-Meier analyses, the OS and PFS rates for SGC patients at 3, 5, and 10 years were 90.7%, 85.1%, and 85.1% and 80.1%, 72.7%, and 63.1%, respectively. The LRRFS and DMFS rates at 3, 5, and 10 years were 87.4%, 82.1%, and 82.1% and 85.3%, 78.4%, and 66.1%, respectively. In multivariable analysis (MVA), the node stage (N stage) was an independent predictor of PFS [P=0.047; hazard ratio (HR) =0.089]. A positive margin was a significant prognostic factor for PFS (P=0.036; HR =4.086), LRRFS (P=0.026; HR =5.064), and DMFS (P=0.011; HR =6.367). Major nerve involvement was significantly correlated with PFS (P=0.034; HR =2.394) and DMFS (P=0.008; HR =2.115). The interval from surgery to radiotherapy predicted PFS (P=0.036; HR =3.934) and DMFS (P=0.012; HR =6.231). Adenoid cystic carcinoma (ACC) was the most common histology (n=21; 35%). For ACC, the 5-year OS, PFS, LRRFS, and DMFS were 100%, 67.7%, 76.2%, and 90.2%, respectively. The most common acute toxicities were mucositis and dermatitis, and xerostomia was the most common late adverse event. Lung metastasis was the most common pattern of distant failure.

CONCLUSIONS

N stage, positive margin, major nerve involvement, and interval from surgery to radiotherapy were important factors associated with PFS, LRRFS, and DMFS. Postoperative IMRT leads to improved survival for SGC patients, with acceptable toxicities.

The Epidemiology of Salivary Glands Pathologies in Adult Population over 10 Years in Poland-Cohort Study

Background: The aim of this study was a comprehensive analysis of the incidence of different salivary gland pathologies in the adult population of Poland. Methods: A retrospective analysis of salivary gland pathologies diagnosed in Poland in 2010–2019 based on the National Health Fund (NHF) database was performed. Non-neoplastic diseases, and benign and malignant lesions were identified using ICD-10 codes. Demographic characteristics, incidence rates, and the number of inpatient and outpatient medical services were analyzed. Results: Salivary gland pathologies were diagnosed in 230,589 patients over 10 years (85.5% were non-neoplastic lesions, 11.53% benign and 2.93% malignant neoplasms). Incidence rate for all pathologies was 59.94/100,000. The mean incidence for malignant neoplasms was 1.78, and decreasing trend was observed over the analyzed period. Contrarily, for benign neoplasms (mean incidence—6.91), an increase in numbers was noted annually. The incidence for non-malignant lesions was quite stable (mean: 51.25) over the time. The highest number of medical services per patient concerned malignant neoplasms (on average, two hospital stays, and eleven outpatient consultations). Conclusions: An increase of benign salivary gland tumors, and a decrease of malignant neoplasms was observed during the studied period. The number of medical services related to salivary gland pathologies increased during the period under study.

High-grade salivary gland cancer: is surgery followed by radiotherapy an adequate treatment to reach tumor control? Results from a tertiary referral centre focussing on incidence and management of distant metastases

Purpose

Salivary Gland cancer (SGC) is a rare and heterogenous group of tumors. Standard therapeutic options achieve high local but poor distant control rates, especially in high-grade SGC. The aim of this monocentric study was to evaluate patterns of recurrence and its treatment options (local ablative vs. systemic) in a homogenously treated patient population with high-grade SGC after surgery and radio(chemo)therapy.

Methods

Monocentric, retrospective study of patients with newly diagnosed high-grade salivary gland cancer. We retrospectively reviewed clinical reports from 69 patients with high-grade salivary gland cancer in a single-center audit. Survival rates were calculated using the Kaplan–Meier method and prognostic variables were analyzed (univariate analysis: log-rank test; multivariate analysis: Cox regression analysis).

Results

The median time of follow-up was 31 months. After 5 years, the cumulative overall survival was 65.2%, cumulative incidence of local recurrence was 7.2%, whereas the cumulative incidence of distant metastases was 43.5% after 5 years. 30 of 69 patients developed distant metastases during the time of follow-up, especially patients with adenoid cystic carcinoma, salivary duct carcinoma, adenocarcinoma NOS and acinic cell carcinoma with high-grade transformation. The most common type of therapy therefore was chemotherapy (50%). 85.7% of patients with local ablative therapy of distant metastases show disease progression during follow-up afterwards.

Conclusion

With surgery and radio-chemotherapy, a high rate of loco-regional control is reached, but over 40% of patients develop distant metastases in the further follow-up which usually present a diffuse pattern involving in a diffuse metastases. Therefore, in the future, intensified interdisciplinary combination therapies even in the first-line treatment in certain subtypes of high-grade SGC should be investigated.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07024-9.

Patterns of care, toxicity and outcome in the treatment of salivary gland carcinomas: long-term experience from a tertiary cancer center

Background

Salivary gland carcinomas (SGC) cover a heterogeneous group of malignancies with a lack of data of high-level evidence.

Methods

Clinical data of 127 patients treated for SGC at a university cancer center between 2002 and 2017 were analyzed retrospectively. The association of clinicopathological characteristics, treatment modalities, adverse events, and outcome was assessed.

Results

Patients received surgery (n = 65), surgery followed by (chemo-)radiotherapy (n = 56), or primary (chemo-)radiotherapy (n = 6). Injury to the cranial nerves or their branches was the most frequent surgical complication affecting 40 patients (33.1%). Ten year overall and progression-free survival rates were 73.2% and 65.4%, respectively. Parotid tumor site, advanced tumor, and positive nodal stage remained independent negative prognostic factors for overall survival, loco-regional and distant tumor control in multivariate analysis.

Conclusions

Optimizing treatment strategies for SGC, depending on distinct clinicopathological factors, remains challenging due to the low incidence rates of the disease.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-06652-5.