Tamoxifen for salivary gland adenoid cystic carcinoma: report of two cases

An Overview on the Histogenesis and Morphogenesis of Salivary Gland Neoplasms and Evolving Diagnostic Approaches

Simple Summary

Diagnosing salivary gland neoplasms (SGN) remain a challenge, given their underlying biological nature and overlapping features. Evolving techniques in molecular pathology have uncovered genetic mutations resulting in these tumors. This review delves into the molecular etiopatho-genesis of SGN, highlighting advanced diagnostic protocols that may facilitate the identification and therapy of a variety of SGN.

Abstract

Salivary gland neoplasms (SGN) remain a diagnostic dilemma due to their heterogenic complex behavior. Their diverse histomorphological appearance is attributed to the underlying cellular mechanisms and differentiation into various histopathological subtypes with overlapping fea-tures. Diagnostic tools such as fine needle aspiration biopsy, computerized tomography, magnetic resonance imaging, and positron emission tomography help evaluate the structure and assess the staging of SGN. Advances in molecular pathology have uncovered genetic patterns and oncogenes by immunohistochemistry, fluorescent in situ hybridization, and next–generation sequencing, that may potentially contribute to innovating diagnostic approaches in identifying various SGN. Surgical resection is the principal treatment for most SGN. Other modalities such as radiotherapy, chemotherapy, targeted therapy (agents like tyrosine kinase inhibitors, monoclonal antibodies, and proteasome inhibitors), and potential hormone therapy may be applied, depending on the clinical behaviors, histopathologic grading, tumor stage and location, and the extent of tissue invasion. This review delves into the molecular pathways of salivary gland tumorigenesis, highlighting recent diagnostic protocols that may facilitate the identification and management of SGN.

Multicentre clinicopathological study of adenoid cystic carcinoma: A report of 296 cases

Aims

Adenoid cystic carcinoma (ACC) is a distinctive tumour. Limited studies involving a large population have reported multicentre systematic analyses of the clinical, pathological and immunohistochemical (IHC) features of ACC as well as the potential role of IHC markers in the prognosis of ACC.

Methods and Results

The clinical, histopathological and IHC data of 296 cases obtained from two tertiary hospitals were analysed. The age at onset ranged from 12 to 87 years with a median age of 52 years. The male‐to‐female ratio was 1:1.3. Patients with ACC arising from the lacrimal gland were younger than those with tumours arising from other sites. Patients with tumours in the extra auditory canal and nasopharynx were older than those with tumours in other locations. Histopathologically, solid type ACC was the most frequent in the nasal cavity and paranasal sinus (6/51) group. Tumours arising from the oral cavity most commonly showed perineural invasion (10/60) and margin positivity (11/60). IHC analyses showed that CK8/18, CK7, CK14, epithelial membrane antigen and CD117 were expressed in 35/35 (100%), 87/88 (98.8%), 26/27 (96.2%), 42/43 (97.6%) and 113/120 (94.1%) patients, respectively. CK5/6, P63, smooth muscle actin, calponin and S100 were positively expressed in 73/73 (100%), 111/124 (89.5%), 38/43 (88.3%), 41/50 (82.0%) and 61/92 (66.3%) cases, respectively. S100 proteins were expressed in 54 (54/77) primary cases and two (2/9) metastatic cases (p = 0.013).

Conclusions

ACC is a distinctive tumour that mainly affects middle‐aged and elderly individuals, with a mild female predominance. Loss of expression of S100 proteins may be a poor prognostic factor associated with metastasis.

Polymorphic variants of drug-metabolizing enzymes alter the risk and survival of oral cancer patients

The present study investigated the prevalence of CYP2D6*4, CYP3A5*3 and SULT1A1*2, using PCR-RFLP, in normal and oral cancer (OC) patients that were stratified by OC subtype and gender. The risk of cancer, 5-year cumulative survival and hazard's ratio (HR) with respect to risk factors and clinical factors were estimated using Fisher's exact test, Kaplan-Meier analysis, and Cox proportional hazards models. CYP2D6*4 'GA' lowered the risk of buccal mucosa cancer (BMC) in males (OR = 0.37), whereas, 'G' allele of CYP3A5*3 increased risk of tongue cancer (TC) (OR = 1.67). SULT1A1*2 'GA' increased the risk of TC (OR = 2.36) and BMC (OR = 3.25) in females. The 5-year survival of the patients depended on factors like age, lymphovascular spread (LVS), perinodal spread (PNS), recurrence, tobacco, and alcohol. CYP3A5*3 'AG' and 'GG' had decreased the hazard ratio (HR) for BMC females when inflammatory infiltrate alone or along with other covariates, LVS, PNI, PNS, metastasis, recurrence, and relapse was adjusted. Similarly, CYP3A5*3 'AG' decreased the risk of death (HR = 0.05) when the grade was adjusted. SULT1A1*2 'GA' had decreased HR for TC males (HR = 0.08) after adjusting for inflammatory infiltrate, LVS, perineural invasion (PNI), PNS, metastasis, recurrence, and relapse. Further, our bioinformatics study revealed the presence of a CpG island within the CYP2D6 and a CTCF binding site upstream of CYP2D6. Interestingly, three CpG islands and two CTCF binding sites were also identified near the SULT1A1. In conclusion, the SNPs altered risk and survival of BMC and TC differentially in a gender specified manner, that varied with clinical and risk factors.

Risk of breast cancer in women after a salivary gland carcinoma or pleomorphic adenoma in the Netherlands

Salivary and mammary gland tumors show morphological similarities and share various characteristics, including frequent overexpression of hormone receptors and female preponderance. Although this may suggest a common etiology, it remains unclear whether patients with a salivary gland tumor carry an increased risk of breast cancer (BC). Our purpose was to determine the risk of BC in women diagnosed with salivary gland carcinoma (SGC) or pleomorphic adenoma (SGPA). BC incidence (invasive and in situ) was assessed in two nationwide cohorts: one comprising 1567 women diagnosed with SGC and one with 2083 women with SGPA. BC incidence was compared with general population rates using standardized incidence ratio (SIR). BC risk was assessed according to age at SGC/SGPA diagnosis, follow‐up time and (for SGC patients) histological subtype. The mean follow‐up was 7.0 years after SGC and 9.9 after SGPA diagnosis. During follow‐up, 52 patients with SGC and 74 patients with SGPA developed BC. The median time to BC was 6 years after SGC and 7 after SGPA. The cumulative risk at 10 years of follow‐up was 3.1% after SGC and 3.5% after SGPA (95% Confidence Interval (95%CI) 2.1%–4.7% and 2.6%–4.6%, respectively). BC incidence was 1.59 times (95%CI 1.19–2.09) higher in the SGC‐cohort than expected based on incidence rates in the general population. SGPA‐patients showed a 1.48 times (95%CI 1.16–1.86) higher incidence. Women with SGC or SGPA have a slightly increased risk of BC. The magnitude of risk justifies raising awareness, but is no reason for BC screening.

Carcinoma ex pleomorphic adenoma: case report and options for systemic therapy

The most common benign salivary tumour is a pleomorphic adenoma. Transformation to malignancy, carcinoma ex pleomorphic adenoma (cxpa), occurs in 6% of cases. Management focuses on surgical resection and radiotherapy; however, rare cases require systemic management. We present the case of a 60-year-old woman with a cxpa of the left parotid gland who required systemic therapy for locally recurrent disease. Treatment options were guided by the literature concerning malignant salivary gland tumour and by whole-genome and transcriptome sequencing of the tumour. The patient received multiple systemic agents during the course of her disease, with cyclophosphamide-doxorubicin-cisplatin providing the best control (partial response). Genomeand transcriptome-directed therapy, including sorafenib and vismodegib, were utilized with limited clinical benefit. Malignant transformation in cxpa is a complex process, and therapy directed at a single tumour pathway might not be sufficient to control disease.

New concepts of personalized therapy in salivary gland carcinomas

Salivary gland carcinomas are rare tumours and therapy strategies are less standardized than in lung, gastric or breast cancer. Therapy is based on surgery, but not all carcinomas are completely resectable, e.g. because carcinomas often show infiltration of nerves. For further therapy decision pathology is recommended, but evaluation of potential targets for personalized therapy is not part of the routine panel. Many salivary gland carcinomas can be resistant to radio- and/or chemotherapy, which limits therapeutic options. This review summarizes new concepts for personalized therapy in salivary gland carcinoma patients. Targeting growth receptors HER2, EGFR, AR and ER is possible but, in some studies, potential target molecules were not adequately tested before therapy. In addition, approximately 20-25% of carcinomas have RAS mutation (mainly H-RAS), which could explain resistance to therapy. Possible therapy options in the future could be immunomodulation (inhibition of PDL1/PD1 signalling), nanoparticles (gold nanoparticles conjugated to cetuximab can increase radiosensitivity) and drug delivery systems (trastuzumab emtansine/T-DM1).

Cytogenetic and immunohistochemical biomarker profiling of therapy-relevant factors in salivary gland carcinomas

OBJECTIVES

There is currently no established algorithm for the molecular profiling of therapy-relevant defects in salivary gland carcinomas (SGC). HER2 overexpression in a subfraction of SGC and low frequencies of EGFR mutations are known. Here, we established receptor and cell signalling profiles of 17 therapy-relevant factors and propose a molecular diagnostic algorithm for SGC.

MATERIALS AND METHODS

Formalin-fixed and paraffin-embedded tissue samples from SGC (n = 38) were analysed with immunohistochemistry and fluorescence in situ hybridisation (FISH).

RESULTS

Two or more expressed receptors and/or receptor gene amplification were detectable in eight of 38 (21%) tumours: HER2 3+/AR 1+, HER3 gene amplification/AR 1+/EGFR 1+, ER 3+/AR 1+, EGFR 2+/PR 1+ and EGFR 2+/PR 1+/AR 1+. No FGFR1-3, MET, ALK1, ROS1, RET, BRAF nor VEGFA defects were detectable, and ERCC1 was not overexpressed. No PD1+ tumour-infiltrating T cells were detectable.

CONCLUSION

Personalised therapy of patients with salivary gland carcinomas should include HER2 and EGFR signalling testing and, in negative cases, evaluation of rare potential target molecules. ERCC1 and PD1 do not appear to be reliable markers for the decision for or against chemotherapy or immunotherapy, respectively.

Adenoid cystic carcinoma of the lung: Response to tamoxifen after chemoradiation

Primary adenoid cystic carcinoma of the lung is a rare subtype of lung cancer with a prolonged natural history but is difficult to completely resect surgically due to its proximal location. Hence radiotherapy plays a role for local control of these cancers. The role of systemic therapies in the treatment of adenoid cystic carcinoma of the lung remains unclear. Isolated case reports have previously described the treatment of primary adenoid cystic carcinoma of the lung with tamoxifen, resulting in partial control. We report the first case of primary adenoid cystic carcinoma of the lung treated with primary chemoradiotherapy due to unresectable location of the tumor, and disease stabilization with symptomatic response to tamoxifen following tumor recurrence. There is a need for further studies to investigate the role of anti-hormonal therapies in the treatment of adenoid cystic carcinoma of the lung.

Clinicopathologic predictors of recurrence and overall survival in adenoid cystic carcinoma of the head and neck: a single institutional experience at a tertiary care center

BACKGROUND

The purpose of this study was to determine factors that impact recurrence and long-term survival of head and neck adenoid cystic carcinoma (ACC).

METHODS

We conducted a retrospective review of 87 patients with head and neck ACC who were evaluated between 1992 and 2009. Staining for Ki-67, p53, α-estrogen receptor (αER), and progesterone receptor (PR) was performed.

RESULTS

Forty men (46%) and 47 women (54%) were included in this study. Median follow-up for patients was 98 months. Five-year recurrence-free and overall survival (OS) rates were 56% and 81%, respectively. Ki-67 and p53 expression was observed in 5 (6%) and 2 (2%) patients, respectively. αER and PR were all negative. The most important determinants of disease-free survival (DFS) were perineural invasion (PNI; p = .001) and female sex (p = .027). Disease site (major vs minor salivary gland) was the only predictor of worse OS on multivariate analysis.

CONCLUSION

Perineural invasion, female sex, and disease site were the most consistent predictors of poor outcome in head and neck ACC.

Immunohistochemical expression of oestrogen receptor-α and progesterone receptor in salivary gland tumours

BACKGROUND

The mammary and salivary glands are tubulo-acinar exocrine glands, sharing similar morphological characteristics and tumour histology. It is logical to postulate that they may have similar tumour biology. This study was carried out to define the expression of oestrogen-α (ER-α) and progesterone (PR) in salivary gland tumours (SGTs) presenting at the University College Hospital, Ibadan.

METHODS

Formalin-fixed, paraffin-embedded tissue samples of different salivary gland neoplasms were processed for antibodies to ER-α and PR using the specifications of the manufacturer. Two independent investigators reviewed the slides scoring the pattern and intensity of staining as follows: negative (0), weakly positive (+1), moderately positive (+2) and strongly positive (+3). Data were analysed using version 16 of the Statistical Package for Social Sciences (SPSS16). The level of significance was set at P < 0.05.

RESULTS

A total of 40 SGTs from 19 males (47.5%) and 21 females (52.5%) were utilised. There were 15 benign and 25 malignant SGTs. ER expression in benign SGTs was 6.7%, while in malignant SGTs, it was 28.0%. There was no statistically significant difference in the gender and mean age distribution between patients with or without positive ER-α expression (χ(2) = 0.37, P = 0.59 Fisher's exact test; t = 0.054, P = 0.96, respectively). About 66.7% of high-grade SGTs was positive for ER while only 20% of the low-grade lesions were positive.

CONCLUSION

This study showed that ER-α was expressed more in the high-grade malignant SGTs compared with the low-grade malignant SGTs and the benign SGTs.

Prognostic value of expression of molecular markers in adenoid cystic cancer of the salivary glands compared with lymph node metastasis: a retrospective study

BACKGROUND

Adenoid cystic cancer arising in the salivary glands has distinctive features such as perineural invasion, distant metastasis, and a variable prognosis. In salivary gland cancer, c-kit, EGFR, and VEGF are representative molecular markers that may predict remnant and recurrent tumors. In this study, the expression of c-kit, EGFR, and VEGF in adenoid cystic cancer was evaluated, and the relationships between the expression of these markers and the clinical findings were investigated.

METHODS

The medical records of 48 patients who were treated for parotid adenoid cystic cancer from January 1990 to January 2006 were reviewed. The tumor location, size, histological subtypes, perineural invasion, the resected margin status, and lymph node metastasis were assessed. Immunohistochemical staining and semiquantitative analysis of c-kit, EGFR and VEGF were performed. The relationship between the expression of each marker and the clinicopathological factors were analyzed.

RESULTS

Positive c-kit immunostaining was present in 45 patients (94%), with weak positivity (+1) in 23, moderate positivity (+2) in 19 and strong positivity (+3) in three. Positive EGFR immunostaining was observed in 27 (56%), with weak positivity (+1) in 19 and moderate positivity (+2) in eight with no strong positive staining. Positive VEGF immunostaining was present in 42 patients (88%) with weak positivity (+1) in 12, moderate positivity (+2) in 17, and strong positivity (+3) in 13. Only the expression of VEGF was significantly higher in parotid gland tumors than in any other gland (P = 0.032). Marginal involvement was associated with strong VEGF expression (P = 0.02). No marker was significantly correlated with recurrence or the survival rate. Lymph node status was related to the survival rate.

CONCLUSIONS

The expression of c-kit, EGRF, and VEGF had no predictive value for recurrence or the prognosis of adenoid cystic cancer. Only the lymph node status was related to the prognosis.

Systemic therapy in the management of metastatic or advanced salivary gland cancers

Salivary gland cancers are very rare tumors. They are characterized by a histologic heterogeneity and a poor outcome. According to this rarity, few prospective data are available to date. No standard recommendations could be held for the use of systemic therapy in these tumors. Several case reports and small studies have investigated the contribution of different agents of chemotherapy. With the extension of molecular biology approach in oncology several signaling pathways have been discovered in different cancers including salivary gland cancers; thus a number of targeted therapies have been investigated. This paper reviewed exhaustively the studies investigating the role of systemic therapies (chemotherapy, targeted therapy, hormone therapy) in salivary gland cancers.

Systemic therapy in the management of metastatic or advanced salivary gland cancers

Salivary gland cancers are very rare tumors. They are characterized by a histologic heterogeneity and a poor outcome. According to this rarity, few prospective data are available to date. No standard recommendations could be held for the use of systemic therapy in these tumors. Several case reports and small studies have investigated the contribution of different agents of chemotherapy. With the extension of molecular biology approach in oncology several signaling pathways have been discovered in different cancers including salivary gland cancers; thus a number of targeted therapies have been investigated. This paper reviewed exhaustively the studies investigating the role of systemic therapies (chemotherapy, targeted therapy, hormone therapy) in salivary gland cancers.

Oestrogen receptor β in adenoid cystic carcinoma of salivary glands

AIMS

This study aimed to describe the expression of oestrogen receptor (ER)α, ERβ and aromatase in salivary gland adenoid cystic carcinoma (ACC).

METHODS AND RESULTS

ERα, ERβ and aromatase expression was analysed by immunohistochemistry in tissue microarray blocks from 38 cases of ACC and seven normal salivary glands. The intracellular localization and amount of total protein expression were investigated by immunofluorescence and western blotting in an ACC cell line. Western blotting analysis showed overexpression of ERα, ERβ and aromatase in the ACC cell line; however, with immunofluorescence, only ERβ was shown to be expressed in the nucleus. Immunohistochemistry revealed positive nuclear expression of ERβ, positive cytoplasmic expression of aromatase and a lack of ERα expression as compared with normal salivary glands.

CONCLUSIONS

The nuclear expression of ERβ indicates that oestrogen may be active in ACC and possibly able to mediate E2-targeted gene transcription. This study strongly suggests that ERβ may be involved in tumour progression, playing a role in tumour development, and thus corroborating the indication for ER antagonists in the clinical control of ACC. This study opens a new perspective on the potential use of anti-oestrogens and aromatase inhibitors as therapeutic agents against ACC.

Novel therapeutic strategies for malignant salivary gland tumors: lessons learned from breast cancer

Malignant salivary gland tumors (MSGTs) account for 2–6% of all head and neck cancers. Despite the rarity, MSGTs have been of great interest due to a wide variety of pathological features and high metastasis rates resulting in poor prognosis. Surgical resection followed by radiation therapy represents the main treatment of this malignancy. Adjuvant therapy is reserved for the management of local recurrence, no longer amenable to additional local therapy, and for metastasis. Based on the studies from other types of tumors, particularly breast cancer, the expression and function of sex steroid hormone receptors in cancer have been extensively studied and applied to diagnosis and treatment. Although a number of studies in MSGTs have been published, the rationale for hormone therapy is still controversial due to the disparate results and insufficient number of cases. However, some recent reports have demonstrated that certain salivary gland neoplasms are similar to breast cancer, not only in terms of the pathological features, but also at the molecular level. Here, we shed light on the biological similarity between MSGTs and certain types of breast cancer, and describe the potential use of hormone and additional therapies for MSGTs.

Salivary glands - "an unisex organ'?

Usually no distinction is made between female and male salivary glands although cyclic changes of and ⁄ or differences in serum and salivary sex steroid concentrations characterize women and men. Moreover, sexual dimorphism is well recognized in salivary glands of rodents.Salivary glands contain estrogen and androgen receptors and are, according to modern high throughput technologies,subjected to gender differences not explainable by gene dose effects by the X chromosome alone. Because sex steroids are lipophilic, it is often thought that approximately 10% of them passively diffuse from plasma to saliva. Indeed, saliva can find use as sample material in sports medicine, pediatrics, veterinary medicine and behavioral sciences. Last but not least, humans and other primates are unique in that they have a reticular zone in their adrenal cortex, which produces dehydroepiandrosterone and androstendione pro-hormones. These are processed in peripheral tissues, not only in female breast and uterus and male prostate, but also in salivary glands by an intracrine enzymatic machinery to active 17b-estradiol,dihydrotestosterone and others, to satisfy and buffer against a constantly changing needs caused by circadian,menstrual, pregnancy and chronobiological hormonal changes in the systemic circulation. Female dominance of Sjögren's syndrome and certain forms of salivary gland cancer probably reflect these gender-based differences.

Chemotherapy and targeted therapy in adenoid cystic carcinoma of the head and neck: a review

Adenoid cystic carcinoma (ACC) is an uncommon tumor usually arising in the head and neck region, mainly in the salivary glands. It demonstrates an indolent prolonged course and is characterized by perineural invasion. Primary treatment of local and locoregional disease consists mainly of surgery and/or irradiation. During follow-up these patients frequently develop local recurrences and distant metastases, especially in the lung, although long-term survival is possible. The role of chemotherapy in ACC is limited, and studies with only a limited number of patients are performed. In this article we review the literature on chemotherapy regimens, including monotherapy and combination chemotherapy schedules, as well as the new targeted therapies.