Imatinib mesylate can induce objective response in progressing, highly expressing KIT adenoid cystic carcinoma of the salivary glands

Liver metastasis as the initial clinical manifestation of sublingual gland adenoid cystic carcinoma: A case report

BACKGROUND

Adenoid cystic carcinoma (ACC) is a common malignant tumor of salivary gland. The lung and liver are frequent sites of distant metastasis. Liver metastasis as the initial clinical manifestation of sublingual gland ACC is very rare.

CASE SUMMARY

A 51-year-old Chinese woman presented with a painless mass in the right lobe of liver. The tumor was composed of ductal cells and myoepithelial cells with a morphology including tubiform and cribriform structures. Immunostaining results showed ductal cells positive for CK7, CK14, CK19, CD117, and 34βE12, and negative for MYB, vimentin, ER, PR, and CEA. The myoepithelial cells were positive for p63, calponin and CK5/6. Metastatic salivary ACC was considered, and a sublingual gland mass was revealed by computed tomography. Histological evaluation confirmed primary sublingual gland ACC. Fluorescence in situ hybridization (FISH) did not find an MYB-NFIB fusion gene in specimens from either the primary or metastatic ACC tumors. The sublingual gland ACC relapsed in 20 mo. The recurrent lesion disappeared following local radiation therapy and computed tomography-guided radioactive seed implantation. The patient remains in good condition until now.

CONCLUSION

Metastatic sublingual gland ACC with initial clinical manifestation as a liver mass is very rare, and was pathologically confirmed in this patient by its histological appearance. Primary hepatic tumors and metastatic carcinomas should be included in the differential diagnosis. Immunohistochemical detection of MYB protein and MYB-NFIB fusion gene detection by FISH can be helpful, but occasional negative results confuse the diagnosis.

Salivary Gland Carcinoma: Novel Targets to Overcome Treatment Resistance in Advanced Disease

Salivary gland carcinomas (SGCs) account for <5% of head and neck malignant neoplasms, further subcategorized in over 20 histological subtypes. For the most part, treatment for advanced disease is guided by morphology. SGCs in general respond poorly to a wide array of standard chemotherapy, with short durability, and significant toxicity. More recently, next-generation sequencing provided significant input on the molecular characterization of each SGC subtype, not only improving diagnostic differentiation between morphologically similar tumor types but also identifying novel driver pathways that determine tumor biology and may be amenable to targeted therapy. Among the most common histological subtype is adenoid cystic carcinoma, which often harbors a chromosome translocation resulting in an MYB-NFIB oncogene, with various degrees of Myb surface expression. In a smaller subset, NOTCH1 mutations occur, conferring a more aggressive pattern and potential sensitivity to Notch inhibitors. Salivary duct carcinomas may overexpress Her-2 and androgen receptors, with promising clinical outcomes after exposure to targeted therapies approved for other indications. Secretory carcinoma, previously known as mammary analog secretory carcinoma, is distinguished by an ETV6-NTRK3 fusion that can both help differentiate it from its morphologically similar acinar cell carcinoma and make it susceptible to Trk inhibitors. In the present article, we discuss the molecular abnormalities, their impact on tumor biology, and therapeutic opportunities for the most common SGC subtypes and review published and ongoing clinical trials and future perspectives for this rare disease.

Evaluation of Multimodality Management of Adenoid Cystic Carcinoma of the Head and Neck

Adenoid cystic carcinoma is a relatively rare tumour arising from salivary glands of head and neck region. Surgery and radiotherapy form standard treatment modalities in the management of this tumor. In this analysis we present results of multimodality treatment in our cohort of patient. This retrospective analysis evaluated results of treatment in forty patients diagnosed with adenoid cystic carcinoma of the head and neck. Evaluation was done to identify prognostic factors affecting the disease free survival. A median disease free survival of 34 ± 2.42 (Median ± SE) versus 10 ± 5.45 months was seen in patients undergoing surgery followed by post operative radiotherapy versus radiotherapy alone (P = 0.01). A radiotherapy dose more than 60 Gy was associated with a better disease free survival compared with patients receiving less than 60 Gy (P = 0.01). Positive surgical margins and perineural invasion were associated with a poor treatment outcome (P = 0.02) Patients with c-kit positive status showed a poor local control rate (P = 0.05).

Spiradenocarcinoma: A Comprehensive Data Review

INTRODUCTION

Spiradenocarcinomas (SCs) are rare and potentially aggressive skin adnexal tumors. Optimal treatment has not yet been established. Experiences with this carcinoma are mostly presented in case reports and few case series.

OBJECTIVE

To generate to a synopsis of published data on SC with regard to diagnostic procedures, treatment, and outcome.

RESULTS

Median patient age was 60 years and sex distribution was balanced. Tumor manifestations were evenly distributed within the sweat gland carrying skin. The most commonly reported symptom was accelerated growth of a longstanding indolent lesion, typically present for more than 2 years. Metastatic spread to the lung, bone, lymph nodes, liver, kidney, and breast has been documented. For staging computed tomography (CT) and positron emission tomography-CT are recommended, especially for detection of hematogenic metastases and lymph node involvement. Clear resection margins and tumor free regional lymph nodes reduce recurrence and carcinoma related death. Although low-grade SCs were reported over 3 times more often, high-grade carcinomas show a greater likelihood for recurrence and lethal outcome.

CONCLUSION

Suspicion of an SC should lead to performance of a magnetic resonance imaging for defining tumor extent, and a fludeoxyglucose positron emission tomography-CT for detection of metastases. Radical tumor excision and resection of tumor involved regional lymph nodes are essential for a curative approach. Histopathological evaluation should involve determination of tumor differentiation grade, because high-grade carcinomas seem to have a much more aggressive behavior. Excision of distant metastases has no therapeutic value. Follow-up needs to be carried out in short intervals with frequent imaging.

Salivary gland stem cells: A review of development, regeneration and cancer

Salivary glands are responsible for maintaining the health of the oral cavity and are routinely damaged by therapeutic radiation for head and neck cancer as well as by autoimmune diseases such as Sjögren's syndrome. Regenerative approaches based on the reactivation of endogenous stem cells or the transplant of exogenous stem cells hold substantial promise in restoring the structure and function of these organs to improve patient quality of life. However, these approaches have been hampered by a lack of knowledge on the identity of salivary stem cell populations and their regulators. In this review we discuss our current knowledge on salivary stem cells and their regulators during organ development, homeostasis and regeneration. As increasing evidence in other systems suggests that progenitor cells may be a source of cancer, we also review whether these same salivary stem cells may also be cancer initiating cells.

Management of salivary gland carcinomas - a review

Salivary gland carcinomas are a heterogeneous group of tumors with many histological subtypes which occur in both major and minor salivary glands. However, they have a relatively low of incidence. Their rarity limits study size and the ability to perform phase III trials. Therefore, to date, the entire management is usually varied. Certain published studies have paid more attention to the systemic therapy in the management of metastatic or locally recurrent salivary gland cancer, while little effort has been made to study the entire management for this lesions. Although results of treatment for patients with salivary gland carcinoma have improved in recent years, the treatment of salivary gland cancers is still not standardized. And some patients who haven’t received optimal treatment strategies had a reduced survival. In this review, the topics covered include surgery and radiotherapy, selective neck dissection, chemotherapy, and targeted therapy, which aimed to summarize the optimal management approaches and to develop recommendations for managing this lesions. For these rare cancers, there is also a need for a determined, coordinated effort to conduct high-quality clinical trials.

New Developments in Salivary Gland Pathology: Clinically Useful Ancillary Testing and New Potentially Targetable Molecular Alterations

Accurate diagnosis of salivary gland tumors can be challenging because of the many diagnostic entities, the sometimes extensive morphologic overlap, and the rarity of most tumor types. Ancillary testing is beginning to ameliorate some of these challenges through access to newer immunohistochemical stains and fluorescence in situ hybridization probes, which can limit differential diagnostic considerations in some cases. These ancillary testing strategies are especially useful in small biopsy samples, including aspiration cytology. Molecular techniques are also expanding our understanding of salivary gland tumor pathology and are helping to identify potential targets that may improve treatment for some of these tumors. Here, we summarize the clinical use of new immunohistochemical markers in our practice and review the current understanding of chromosomal rearrangements in salivary gland tumor pathology, emphasizing the prospects for exploiting molecular alterations in salivary gland tumors for diagnosis and targeted therapy. We find that immunohistochemistry and fluorescence in situ hybridization are powerful tools toward the diagnosis of salivary gland tumors, especially when used in a systematic manner based on morphologic differential-diagnostic considerations. As new targeted therapies emerge, it will become increasingly vital to incorporate appropriate molecular testing into the pathologic evaluation of salivary gland cancers.

Adenoid Cystic Carcinoma of Vulva-11 Years' Single-Institution Experience

INTRODUCTION

Adenoid cystic carcinoma of vulva (ACC-vulva) is an extremely rare entity with <100 cases reported in the literature so far.

OBJECTIVE

To study the clinical profile and outcome of ACC-vulva treated at a tertiary cancer care centre in South India.

METHODS

This is a retrospective, record-based study of histopathologically confirmed cases of ACC-vulva treated at our centre from January 2005 to March 2016.

RESULTS

Only four patients were diagnosed with ACC-vulva during the 11-year period under study. The longest duration of follow-up was 129 months. The age at diagnosis ranged from 32 to 43 years, with a median of 40 years. All patients were married, parous and premenopausal and presented with a painless unilateral vulval swelling. All patients had involvement of the Bartholin's gland site with normal overlying skin. In all patients, wide excision was performed. Unilateral inguinal node dissection was done in one case. Perineural infiltration was documented in two cases, while positive excision margins were present in three cases. None of the patients had any lymph node involvement at diagnosis or during follow-up. Two patients had recurrence of disease. The disease-free interval was 23 months for one patient and 118 months for the other. In both, local (vulval) and distant (multiple lung) metastases were detected simultaneously.

CONCLUSION

Adenoid cystic carcinoma of vulva is an extremely rare, slowly progressing neoplasm mostly involving the Bartholin's gland. The usual treatment includes wide excision and adjuvant radiotherapy (if required). There may be late local and distant recurrence.

KIT (CD117) Expression in Benign and Malignant Sweat Gland Tumors

KIT (CD117, c-kit) is a receptor tyrosine kinase involved in the tumorigenesis of several neoplasms. KIT is expressed by the secretory cells of normal sweat glands. We studied the KIT expression and KIT mutational status in various benign and malignant tumors of eccrine and apocrine glands. We included a total of 108 cases comprising 10 benign and 6 malignant sweat gland tumors, and KIT expression was immunohistochemically detected (positive rate): 10 syringomas (0%), 8 poromas (25%), 20 mixed tumors (40%), 21 spiradenomas (43%), 1 cylindroma (0%), 5 hidradenomas (40%), 7 syringocystadenoma papilliferum cases (0%), 1 papillary hidradenoma (100%), 2 tubulopapillary hidradenomas (50%), 8 hidrocystomas (29%), 2 adenoid cystic carcinomas (100%), 5 porocarcinomas (20%), 6 apocrine carcinomas (33%), 10 extramammary Paget diseases (30%), 1 spiradenocarcinoma (100%), and 1 syringocystadenocarcinoma papilliferum (0%). Most KIT-positive cells were luminal cells, arising from glandular structures. We performed polymerase chain reaction–single-strand conformation polymorphism for detecting KIT mutational status. All cases showed no mutations at hot spots for KIT (exons 9, 11, 13, and 17). KIT mutation does not seem to be mechanism for KIT expression, but the expression may be from native sweat glands.

Systemic therapy for recurrent or metastatic salivary gland malignancies

Salivary gland carcinomas are notoriously resistant to therapy and no standard of care exists. Due to the rarity of these malignancies, various histologies, and wide ranging clinical behavior it has been difficult to standardize systemic therapy. We have reviewed clinical prospective studies in the last 15 years with salivary gland malignancies involving cytotoxic chemotherapy and biologic agents including targeted therapies such as anti-HER-2, anti-EGFR therapies, and therapies directed at c-kit. Although the results of most trials are modest at best, there has been an increase in studies for salivary cancer in recent years and there are several promising treatment approaches in evolution. Every effort should be made to treat salivary gland malignancies under a clinical protocol and/or at a large multidisciplinary practice with clinicians experienced in treating these malignancies.

Phase II trial of dasatinib for recurrent or metastatic c-KIT expressing adenoid cystic carcinoma and for nonadenoid cystic malignant salivary tumors

BACKGROUND

Adenoid cystic carcinoma (ACC) is a subtype of malignant salivary gland tumors (MSGT), in which 90% of cases express cKIT. Dasatinib is a potent and selective inhibitor of five oncogenic protein tyrosine kinases (PTKs)/kinase families including cKIT. We conducted a phase II study to determine the antitumor activity of dasatinib in ACC and non-ACC MSGT.

PATIENTS AND METHODS

In a two-stage design, patients with progressive, recurrent/metastatic ACC (+cKIT) and non-ACC MSGT (separate cohort) were treated with dasatinib 70 mg p.o. b.i.d. Response was assessed every 8 weeks using RECIST.

RESULTS

Of 54 patients: 40 ACC, 14 non-ACC (1, ineligible excluded); M:F = 28 : 26, median age 56 years (range 20-82 years), ECOG performance status 0 : 1 : 2 = 24 : 28 : 2, prior radiation: 44, prior chemotherapy: 21. The most frequent adverse events (AEs) (as % of patients, worst grade 2 or higher) were: fatigue (28%), nausea (19%), headache (15%), lymphopenia (7%), dyspnea (11%), alanine aminotransferase increased (7%), anorexia (7%), vomiting (7%), alkaline phosphatase increased (6%), diarrhea (6%), neutropenia (6%), and noncardiac chest pain (6%). No grade 4 AE occurred, 15 patients experienced a grade 3 AE, primarily dyspnea (5) and fatigue (4), and cardiac toxicity (1 prolonged QTc). Among ACC patients, best response to dasatinib: 1 patient (2.5%) had partial response, 20 patients (50%) had stable disease (SD) (3-14 months), 12 patients (30%) had PD, 2 withdrew, 3 discontinued therapy due to AE, and 2 died before cycle 2. Median progression-free survival was 4.8 months. Median overall survival was 14.5 months. For 14 assessable non-ACC patients, none had objective response, triggering early stopping rule. Seven had SD (range 1-7 months), 4 PD, 2 discontinued therapy due to AE, and 1 died before cycle 2.

CONCLUSION

Although there was only one objective response, dasatinib is well tolerated, with tumor stabilization achieved by 50% of ACC patients. Dasatinib demonstrated no activity in non-ACC MSGT.

Slug silencing inhibited perineural invasion through regulation of EMMPRIN expression in human salivary adenoid cystic carcinoma

Salivary adenoid cystic carcinoma (SACC) is the most frequent salivary gland malignancy with a unique characteristic that has been named perineural invasion (PNI). EMMPRIN is a transmembrane glycoprotein that has been demonstrated to promote PNI in SACC. Slug, one of the most effective promoters of the epithelial-to-mesenchymal transition (EMT), has been found to be associated with PNI in SACC. The aim of the present study was to investigate the roles and relationships of Slug, EMMPRIN, and E-cadherin in the PNI process of SACC. The expression levels of Slug, EMMPRIN, and E-cadherin in 115 primary SACC cases were statistically analyzed by immunohistochemistry. Simultaneously, the SACC cell line SACC-83 was transfected with recombinant plasmids of silencing Slug (si-Slug) and/or silencing EMMPRIN (si-EMMPRIN). The functions of Slug and EMMPRIN in the EMT and PNI process were assessed by reverse transcription PCR (RT-PCR), western blotting, morphological observation, scratch test, migration assay, and in vitro perineural invasion assay. The immunohistochemical statistics revealed that the high expression of Slug and EMMPRIN and the low expression of E-cadherin were significantly associated with the PNI of SACC (P < 0.05). Slug expression was significantly associated with EMMPRIN expression (P < 0.05), and Slug expression and EMMPRIN expression were both significantly negatively associated with E-cadherin expression (P < 0.05). Slug and EMMPRIN silencing both significantly inhibited EMMPRIN expression but promoted E-cadherin expression in SACC-83 cells (P < 0.01). The series of in vitro assays revealed that silencing of Slug, EMMPRIN, or both induced cell morphology changes and inhibited tumor cell motility and PNI ability in SACC-83 cells (P < 0.01). These results suggested that Slug silencing could inhibit the EMT process by downregulating EMMPRIN and then upregulating E-cadherin in the PNI process of SACC. The present study indicated that Slug and EMMPRIN are potential biomarkers and therapeutic targets for the diagnosis and treatment of PNI in human SACC.

c-Kit Expression is Rate-Limiting for Stem Cell Factor-Mediated Disease Progression in Adenoid Cystic Carcinoma of the Salivary Glands

Adenoid cystic carcinoma (ACC) is an aggressive malignant neoplasm of the salivary glands in which c-Kit is overexpressed and activated, although the mechanism for this is as yet unclear. We analyzed 27 sporadic ACC tumor specimens to examine the biologic and clinical significance of c-Kit activation. Mutational analysis revealed expression of wild-type c-Kit in all, eliminating gene mutation as a cause of activation. Because stem cell factor (SCF) is c-Kit's sole ligand, we analyzed its expression in the tumor cells and their environment. Immunohistochemistry revealed its presence in c-Kit–positive tumor cells, suggesting an activation of autocrine signaling. We observed a significant induction of ERK1/2 in the cells. SCF staining was also found in other types of non-cancerous cells adjacent to tumors within salivary glands, including stromal fibroblasts, neutrophils, peripheral nerve, skeletal muscle, vascular endothelial cells, mucous acinar cells, and intercalated ducts. Quantitative PCR showed that the top quartile of c-Kit mRNA expression distinguished ACCs from normal salivary tissues and was cross-correlated with short-term poor prognosis. Expression levels of SCF and c-Kit were highly correlated in the cases with perineural invasion. These observations suggest that c-Kit is potentially activated by receptor dimerization upon stimulation by SCF in ACC, and that the highest quartile of c-Kit mRNA expression could be a predictor of poor prognosis. Our findings may support an avenue for c-Kit-targeted therapy to improve disease control in ACC patients harboring the top quartile of c-Kit mRNA expression.

Cetuximab and platinum-based chemoradio- or chemotherapy of patients with epidermal growth factor receptor expressing adenoid cystic carcinoma: a phase II trial

Background:

Epidermal growth factor receptor (EGFR) is highly expressed in adenoid cystic carcinoma (ACC). The efficacy and toxicity of cetuximab with concomitant platinum-based chemoradio- or chemotherapy in patients with locally advanced or metastatic ACC, respectively, was evaluated.

Methods:

Eligible patients (9 with locally advanced tumour and 12 with metastases) had positive tumour EGFR expression. The cetuximab loading dose (400 mg m⁻²) was followed by 250 mg m⁻² per week. Locally advanced tumours were irradiated (mean dose 65 Gy) and treated with concomitant cisplatin (75 mg m⁻², intravenously). Patients with metastases received concomitant cisplatin and 5-fluorouracil (4 × 1000 mg m⁻²).

Results:

For patients with locally advanced disease (median follow-up: 52 months), the median progression-free survival (PFS) was 64 months and the 2-year overall survival (OS) rate was 100%. For patients with metastases (median follow-up: 72 months), the median PFS and OS were 13 and 24 months, respectively. In both groups the objective response rate was >40%. Skin rash, in-field dermatitis, mucositis and vomiting were the most frequent grade 3/4 adverse events.

Conclusion:

In this single-arm study, the efficacy of cetuximab plus chemoradio- or chemotherapy appeared favourable as compared with historical controls. All side effects were manageable and did not hamper the treatment.

Mutation profiling of adenoid cystic carcinomas from multiple anatomical sites identifies mutations in the RAS pathway, but no KIT mutations

AIMS

The majority of adenoid cystic carcinomas (AdCCs), regardless of anatomical site, harbour the MYB-NFIB fusion gene. The aim of this study was to characterize the repertoire of somatic genetic events affecting known cancer genes in AdCCs.

METHODS AND RESULTS

DNA was extracted from 13 microdissected breast AdCCs, and subjected to a mutation survey using the Sequenom OncoCarta Panel v1.0. Genes found to be mutated in any of the breast AdCCs and genes related to the same canonical molecular pathways, as well as KIT, a proto-oncogene whose protein product is expressed in AdCCs, were sequenced in an additional 68 AdCCs from various anatomical sites by Sanger sequencing. Using the Sequenom MassARRAY platform and Sanger sequencing, mutations in BRAF and HRAS were identified in three and one cases, respectively (breast, and head and neck). KIT, which has previously been reported to be mutated in AdCCs, was also investigated, but no mutations were identified.

CONCLUSIONS

Our results demonstrate that mutations in genes pertaining to the canonical RAS pathway are found in a minority of AdCCs, and that activating KIT mutations are either absent or remarkably rare in these cancers, and unlikely to constitute a driver and therapeutic target for patients with AdCC.

Salivary gland cancer: an update on present and emerging therapies

Malignant salivary gland tumors make up a small proportion of malignancies worldwide, yet vary widely in terms of histology, patterns of spread, and recurrence. A better understanding of this variability will guide appropriate treatment recommendations and lead to improved outcomes. Recent molecular genetic studies have uncovered a translocation-generated gene fusion network in salivary gland carcinomas that can be used for diagnosis, treatment decisions, and development of specific targeted therapies. The gene fusions encode novel fusion oncoproteins that function as transcriptional coactivators, tyrosine kinase receptors, and transcription factors involved in growth-factor signaling and cell-cycle regulation. While surgery currently is the primary therapy for operable tumors, radiation plays an important role in the postoperative setting, as well as in the definitive setting for inoperable lesions. An awareness of the risk factors for tumor recurrence and spread is important for both adjuvant therapy referrals and for radiation treatment planning purposes. Additionally, chemotherapy is being used increasingly in both the concurrent setting as a radiosensitizer, as well as in the palliative setting for metastatic tumors. Future trials investigating concurrent chemotherapy and radiation, as well as the use of targeted agents based on evolving molecular discoveries, will elucidate optimal personalized approaches for this challenging disease.

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.

Mutations in the c-Kit gene disrupt mitogen-activated protein kinase signaling during tumor development in adenoid cystic carcinoma of the salivary glands

The Ras/mitogen-activated protein kinase (MAPK) pathway is considered to be a positive regulator of tumor initiation, progression, and maintenance. This study reports an opposite finding: we have found strong evidence that the MAPK pathway is inhibited in a subset of adenoid cystic carcinomas (ACCs) of the salivary glands. ACC tumors consistently overexpress the receptor tyrosine kinase (RTK) c-Kit, which has been considered a therapeutic target. We performed mutational analysis of the c-Kit gene (KIT in 17 cases of ACC and found that 2 cases of ACC had distinct missense mutations in KIT at both the genomic DNA and messenger RNA levels. These mutations caused G664R and R796G amino acid substitutions in the kinase domains. Surprisingly, the mutations were functionally inactive in cultured cells. We observed a significant reduction of MAPK (ERK1/2) activity in tumor cells, as assessed by immunohistochemistry. We performed further mutational analysis of the downstream effectors in the c-Kit pathway in the genes HRAS, KRAS, NRAS, BRAF, PIK3CA, and PTEN. This analysis revealed that two ACC tumors without KIT mutations had missense mutations in either KRAS or BRAF, causing S17N K-Ras and V590I B-Raf mutants, respectively. Our functional analysis showed that proteins with these mutations were also inactive in cultured cells. This is the first time that MAPK activity from the RTK signaling has been shown to be inhibited by gene mutations during tumor development. Because ACC seems to proliferate despite inactivation of the c-Kit signaling pathway, we suggest that selective inhibition of c-Kit is probably not a suitable treatment strategy for ACC.

Phase II study of cisplatin and imatinib in advanced salivary adenoid cystic carcinoma

Patients with adenoid cystic carcinoma of the salivary glands show over-expression of KIT in a high proportion of cases. Options for systemic treatment are limited in locally advanced and metastatic disease. We explored the efficacy of imatinib and cisplatin combined in this group of patients. A Gehan's two-stage, phase II trial was conducted on 28 patients. Those with progressive, locally advanced, and metastatic disease with an over-expression of KIT were treated with single agent imatinib 800 mg daily for two months, followed by a combination of imatinib 400mg daily and cisplatin 80 mg/m(2) at four-weekly intervals for six cycles. This was followed by maintenance single agent imatinib 400mg daily until the disease progressed. Response was monitored using fluorodeoxyglucose positron emission tomography (FDG-PET) and morphological imaging using computed tomography, magnetic resonance, and chest radiographs (CT/MRI/CXR). Morphological imaging showed partial response in three of 28 patients, and five patients showed a response on FDG-PET. In addition, 19 patients had useful stabilisation of disease. The median time to progression and overall survival was 15 months (range 1-43) and 35 months (range 1-75), respectively. The combination of imatinib and cisplatin was reasonably well tolerated. This combination may provide stabilisation in locally advanced and metastatic adenoid cystic carcinoma of the salivary glands.

Contemporary management of sinonasal cancer

BACKGROUND

Sinonasal cancer is a relatively uncommon entity encountered by head and neck oncologists, rhinologists, and skull base surgeons. Recent innovations in surgical and nonsurgical therapeutic modalities raise the question of whether there has been any measurable improvement for treatment outcomes.

METHODS

A retrospective review of data from recent studies that focus on surgery, radiation, and chemotherapy, or combinations thereof, was conducted.

RESULTS

Surgery continues to be the preferred treatment and provides the best results, albeit with an inherent bias based on patient selection. For advanced disease (T4 lesions), the survival rate remains only modest. Complications of treatment, including both surgical and radiation therapy, have been reduced.

CONCLUSIONS

There is a need to improve the efficacy of treatment for this disease. Recommendations for the future direction of therapeutic investigations are outlined.

Parotid carcinoma: Current diagnostic workup and treatment

In this review we present recent progress in diagnostic workup, prognostic evaluation, treatment options and resulting outcomes. Whenever possible, complete resection remains the mainstay of treatment. Sacrifice of facial nerve branches is reserved for the clinically or electromyographically dysfunctioning facial nerve. Clinical or radiological neck disease demands combined surgery and radiotherapy. Treatment of the N0 neck is indicated for advanced stage-high grade tumors but the question remains unanswered whether this should be surgical or radiotherapeutic elective treatment. Surgery alone will cure low stage, low grade tumors, that show no additional negative prognostic factors following adequate resection. In all other tumors postoperative radiotherapy will improve locoregional control. This approach results in good locoregional control, in a way that distant metastasis remains the typical presentation of treatment failure. In this setting, the results of systemic treatment today remain limited, but a huge effort in the molecular biology field has been done to introduce targeted therapy into this domain of head and neck cancer. Disease control remains variable within the patient population. This variation can increasingly be predicted by systems that incorporate the combined information of multivariately identified and quantified prognostic factors into an individualized prognosis for the parotid carcinoma patient.

Major and minor salivary gland tumors

Malignant salivary gland tumors are rare. The most common tumor site is the parotid. Aetiologic factors are not clear. Nutrition may be a risk factor, as well as irradiation or a long-standing histologically benign tumor that occurs at youth. Painless swelling of a salivary gland should always be considered as suspicious, especially if no sign of inflammation is present. Signs and symptoms related to major salivary gland tumors differ from those concerning minor salivary gland tumors, as they depend on the different location of the salivary gland. Surgical excision represents the standard option in the treatment of resectable tumors of both major and minor salivary glands. Neutron, heavy ions or proton radiotherapy may be a treatment option for inoperable locoregional disease. Surgery, irradiation or re-irradiation are treatment options for local relapse, whereas radical neck dissection is indicated for regional relapses. Metastatic disease may be either treated with radiotherapy or palliative chemotherapy, depending on the site of metastases. For highly selected patients the employment of anti-androgen therapy is indicated.

Receptor tyrosine kinases in sinonasal undifferentiated carcinomas--evaluation for EGFR, c-KIT, and HER2/neu expression

BACKGROUND

Our objective was to identify the expression of epidermal growth factor receptor (EGFR), c-KIT (CD117), and HER2/neu in sinonasal undifferentiated carcinoma (SNUC).

METHODS

Immunohistochemistry for c-KIT (CD117), EGFR, and HER2/neu was performed on paraffin-embedded tissue from SNUC cases. A search for activating mutations in c-kit exons 9, 11, 13, and 17 or gene amplification was undertaken by high-resolution DNA melting curve analysis and fluorescence in situ hybridization (FISH) for c-kit and chromosome 4, respectively.

RESULTS

By immunohistochemistry, 9 of 11 cases (81.8%) were diffusely (4+) positive for c-KIT, 3 of 11 cases (27.3%) were positive for EGFR, and none of the cases were positive for HER2/neu. Neither activating mutations nor gene amplification of c-kit were detected in any of the 8 assessable tumors.

CONCLUSION

c-KIT is frequently expressed in SNUC. However, the overexpression is not due to activating mutations or gene amplification.

Signaling pathways in adenoid cystic cancers: implications for treatment

Adenoid cystic cancers (ACC) in the head and neck are rare yet present a clinical dilemma. Although 5-y survivals are excellent, they have a propensity for late recurrences. Most of these cancers are initially treated with surgery followed by radiation. When recurrences happen, treatment options are limited both by the morbidity and low efficacy of re-irradiation and repeated surgical resection. Reported response rates to chemotherapy are low and targeted therapies may be one option. We, therefore, investigated signaling pathways that may be active in adenoid cystic cancers. Tissues from the last nine ACC patients resected at the University of Iowa were immunohistochemically stained with antibodies for EGFR, phosphorylated (P) Akt, and P-MAPK in order to molecularly characterize these tumors. An ACC cell line (ACC3) was also characterized by western blot. We found that seven of the nine tumor samples had strong expression of P-Akt and 5/9 had P-MAPK. None of them had EGFR expression. In the ACC3 cell line, similar data was found in that there was P-Akt and P-MAPK but no EGFR expression. We tested the HIV protease inhibitor nelfinavir (NFV) which has been shown to inhibit Akt signaling to see its effect on ACC3 cells. Both P-Akt and P-MAPK were inhibited with NFV in ACC3 cells and this resulted in growth inhibition and clonogenic death. In patients where re-irradiation or further surgery is not an option, a trial of NFV may be warranted.

Identification of c-kit gene mutations in primary adenoid cystic carcinoma of the salivary gland

The CD117 (KIT) protein is overexpressed in many human neoplasms including adenoid cystic carcinoma of salivary glands. To evaluate the function of c-kit-activating mutations in adenoid cystic carcinoma of the salivary gland, we studied 14 cases (13 primary, 1 cervical lymph node metastasis) from our institution. KIT protein expression was evaluated by immunohistochemistry using formalin-fixed paraffin-embedded tissue. Mutational analyses of c-kit extracellular (exon 9), juxtamembrane (exon 11) and tyrosine kinase domains (exons 13 and 17) were performed by polymerase chain reaction, clonal selection and DNA sequencing. All 14 cases demonstrated strong KIT expression by immunohistochemistry. Molecular analysis was successful in 8 of 14 cases, and c-kit missense point mutations were detected in seven of eight cases (88%) including seven in exon 11, two in exon 9, two in exon 13 and two in exon 17. Eight silent point mutations were detected in five cases. Two cases contained missense mutations in more than one exon. Different mutations were found in the primary tumor and the cervical lymph node metastasis of one patient. Point mutations in domains similar to those described in gastrointestinal stromal tumors were detected, including Pro551Leu and Lys558Glu (5' end of exon 11), Leu576Phe (3' end of exon 11), Val643Ala (exon 13) and Asn822Ser (exon 17). Additional novel point mutations in exons 9, 11, 13 and 17 were also identified. This study is the first to report c-kit gene mutations in primary adenoid cystic carcinoma of the salivary gland. Identification of such potential gain-of-function mutations in exon 11, and less frequently in exons 9, 13 and 17, suggests that KIT may be involved in the pathogenesis of adenoid cystic carcinoma of salivary glands. Our study raises a prospect of correlation of c-kit mutation and a potential treatment of adenoid cystic carcinoma with tyrosine kinase inhibitor (imatinib).

Immunotherapy for adenoid cystic carcinoma of salivary glands: cancer/testis antigens and 5-aza-2'-deoxycytidine

Adenoid cystic carcinoma of salivary glands is the epithelial tumor. There are amount of malignant occurrences of adenoid cystic carcinoma of salivary glands in the head and neck area. Cancer/testis antigens can be found in various malignant tumors, normal adult testis and occasionally placenta, but not in the other normal adult tissues. This characteristic makes Cancer/testis antigens as potential markers to be applied in immunotherapeutic strategies against cancer. It has been shown that in different tumors, the expression of certain Cancer/testis antigens is activated treated with 5-aza-CdR via the demethylation of their promoter CpG islands. It is logical that multiple Cancer/testis antigens may correlate with the clinicopathologic factors of adenoid cystic carcinoma of salivary glands and be the potential markers of prognosis treated with 5-aza-CdR. So the hypothesis will provide the new direction that we can use Cancer/testis antigens as candidate antigens for adenoid cystic carcinoma of salivary glands immunotherapy due to the high expression rate activated with 5-aza-CdR.

Current concepts in research related to oncogenes implicated in salivary gland tumourigenesis: a review of the literature

BACKGROUND

Salivary gland tumours are relatively uncommon and there exists considerable difficulty in decisions regarding prognosis and management, as well as diagnostic uncertainty that has implications for treatment.

METHOD

Literature pertaining to individual oncogenes has been reviewed and commented upon, specifically looking at the role of these as diagnostic and prognostic markers and as potential targets for treatments.

RESULTS

kit, PLAG1, Mect1-Maml2, HMGIC, HER2/neu, ras, c-fos and Sox-4 all have seminal small-scale studies in the literature with potential for further research and eventual clinical applications.

CONCLUSION

A wide variety of oncogenes are implicated in salivary gland tumourigenesis, with evidence being confined to small murine or in vitro studies more often than not. There are possible roles for different oncogenes in therapeutics, prognosis and management of specific salivary gland tumours.

Epirubicin, cisplatin and protracted venous infusion 5-Fluorouracil chemotherapy for advanced salivary adenoid cystic carcinoma

AIMS

Adenoid cystic carcinoma (ACC) is a rare tumour that usually arises in the salivary glands. Initial management is surgery often combined with adjuvant radiotherapy. Chemotherapy is reserved for treatment of symptomatic recurrence. We evaluated the combination of epirubicin, cisplatin and protracted venous infusion 5-fluorouracil (ECF) in the management of ACC.

MATERIALS AND METHODS

Patients referred for treatment of advanced, symptomatic ACC were considered. The drugs given were epirubicin 50 mg/m(2) 3-weekly, cisplatin 60 mg/m(2) 3-weekly and protracted venous infusion 5-fluorouracil 200 mg/m(2)/day.

RESULTS

Eight patients (median age 46 years) received a median of five cycles of chemotherapy. All patients had had previous surgery, seven had had previous radiotherapy and one had had previous chemotherapy. One patient showed a partial response (duration 34 months) and five showed stable disease (median duration 13.6 months [6.8-15.9+ months]). Median survival was 27 months (3.5-62.3 months).

CONCLUSIONS

The activity of ECF in ACC of the head and neck seems to be similar to the combination of cisplatin and 5-fluorouracil and single-agent epirubicin.

Overexpression of EGFR and absence of C-KIT expression correlate with poor prognosis in salivary gland carcinomas

AIMS

To evaluate the prognostic impact of expression of receptor tyrosine kinases epidermal growth factor receptor (EGFR), HER2, and C-KIT in relation to established clinicopathological parameters in salivary gland carcinomas.

METHODS AND RESULTS

Immunohistochemistry for EGFR, HER2, C-KIT and the proliferation marker Ki67 was performed in 101 cases of salivary gland carcinoma and related to long-term clinical follow-up. Immunopositivity of C-KIT was common in adenoid cystic carcinoma (92%). Lack of C-KIT expression occurred in salivary duct carcinoma (P < 0.001) and was associated with high-grade tumours (P = 0.002), positive lymph nodes (P = 0.002) and high expression of Ki67 (P = 0.001). HER2 was typically expressed in salivary duct carcinomas (83%), but was not associated with any other parameter. EGFR overexpression occurred independently of histological type and clinical parameters. On univariate survival analysis, overexpression of EGFR (P = 0.011) and lack of C-KIT (P = 0.014) were associated with worse prognosis, whereas HER2 was of no prognostic significance. On multivariate analysis, the strongest negative predictor of survival was high proliferative activity measured by Ki67 (P = 0.002), followed by presence of residual tumour (P = 0.006), overexpression of EGFR (P = 0.026) and advanced tumour stage (P = 0.041).

CONCLUSIONS

The expression of receptor tyrosine kinases confers additional prognostic impact on disease-specific survival. EGFR overexpression is an independent negative prognostic factor.

Imatinib in the treatment of solid tumours

The extraordinary success of imatinib in gastrointestinal stromal tumors (GIST) represents a model for molecularly targeted therapy for other solid tumors. Research is currently going to identify the molecular basis of mechanisms of action and drug resistance. In this article, we review recent advances in the clinical management of patients with GISTs treated with imatinib, but also of patients with dermatofibrosarcoma protuberans, chordoma, aggressive fibromatosis, and some other common solid tumors treated with this drug. We reviewed the knowledge of the molecular mechanisms that are basic to imatinib effects in these tumors.

Phase II, open-label study evaluating the activity of imatinib in treating life-threatening malignancies known to be associated with imatinib-sensitive tyrosine kinases

PURPOSE

To evaluate the activity of imatinib in treating advanced, life-threatening malignancies expressing one or more imatinib-sensitive tyrosine kinases.

EXPERIMENTAL DESIGN

This was a phase II, open-label, single arm study. Patients > or = 15 years old with malignancies showing histologic or molecular evidence of expression/activation of imatinib-sensitive tyrosine kinases were enrolled. Patients were treated with 400 or 800 mg/d imatinib for hematologic malignancy and solid tumors, respectively. Treatment was continued until disease progression or unacceptable toxicity. The primary objective was to identify evidence of imatinib activity with tumor response as the primary end point.

RESULTS

One hundred eighty-six patients with 40 different malignancies were enrolled (78.5% solid tumors, 21.5% hematologic malignancies). Confirmed response occurred in 8.9% of solid tumor patients (4 complete, 9 partial) and 27.5% of hematologic malignancy patients (8 complete, 3 partial). Notable activity of imatinib was observed in only five tumor types (aggressive fibromatosis, dermatofibrosarcoma protuberans, hypereosinophilic syndrome, myeloproliferative disorders, and systemic mastocytosis). A total of 106 tumors were screened for activating mutations: five KIT mutations and no platelet-derived growth factor receptor mutations were found. One patient with systemic mastocytosis and a partial response to therapy had a novel imatinib-sensitive KIT mutation (D816T). There was no clear relationship between expression or activation of wild-type imatinib-sensitive tyrosine kinases and clinical response.

CONCLUSION

Clinical benefit was largely confined to diseases with known genomic mechanisms of activation of imatinib target kinases. Our results indicate an important role for molecular characterization of tumors to identify patients likely to benefit from imatinib treatment.

Salivary gland cancers: current treatments, molecular characteristics and new therapies

Salivary gland cancers are relatively rare and quite diverse. Current therapy relies on local ablation. There are few large clinical trials or randomized trials to guide treatment, especially for metastatic disease. This article reviews the epidemiology, staging, molecular characteristics, and treatment evidence for the most common types of salivary cancers and suggests potential future diagnostic and treatment directions. Progress in understanding the molecular and cell biology of salivary gland cancers may lead to the development of targeted therapies in these rare tumors. Multidisciplinary and multi-institutional collaborative studies are needed to help improve survival in salivary gland cancers.

High-resolution array comparative genomic hybridization analysis of human bronchial and salivary adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a rare but distinctive tumor. Oligonucleotide array comparative genomic hybridization has been applied for cataloging genomic copy number alterations (CNAs) in 17 frozen salivary or bronchial tumors. Only four whole chromosome CNAs were found, and most cases had 2-4 segmental CNAs. No high level amplification was observed. There were recurrent gains at 7p15.2, 17q21-25, and 22q11-13, and recurrent losses at 1p35, 6q22-25, 8q12-13, 9p21, 12q12-13, and 17p11-13. The minimal region of gain at 7p15.2 contained the HOXA cluster. The minimal common regions of deletions contained the CDKN2A/CDKN2B, TP53, and LIMA1 tumor suppressor genes. The recurrent deletion at 8q12.3-13.1 contained no straightforward tumor suppressor gene, but the MIRN124A2 microRNA gene, whose product regulates MMP2 and CDK6. Among unique CNAs, gains harbored CCND1, KIT/PDGFRA/KDR, MDM2, and JAK2. The CNAs involving CCND1, MDM2, KIT, CDKN2A/2B, and TP53 were validated by FISH and/or multiplex ligation-dependent probe amplification. Although most tumors overexpressed cyclin D1 compared with surrounding glands, the only case to overexpress MDM2 had the corresponding CNA. In conclusion, our report suggests that ACC is characterized by a relatively low level of structural complexity. Array CGH and immunohistochemical data implicate MDM2 as the oncogene targeted at 12q15. The gain at 4q12 warrants further exploration as it contains a cluster of receptor kinase genes (KIT/PDGFRA/KDR), whose products can be responsive to specific therapies.

Salivary gland carcinomas, paranasal sinus cancers and melanoma of the head and neck: an update about rare but challenging tumors

PURPOSE OF REVIEW

This is a review about recent clinical developments in rare cancers of the head and neck.

RECENT FINDINGS

Progress in molecular biology techniques has allowed the identification of new prognostic factors, and potential molecular-targeted therapies. This is of importance since chemotherapy continues to play a role but is still limited in this group of malignancies. New techniques of irradiation such as intensity-modulated radiotherapy and three-dimensional conformal radiotherapy appear to improve the locoregional control of these tumors. Surgery continues to be the cornerstone of treatment, with a growing interest in the technique of sentinel lymph node biopsy.

SUMMARY

As salivary gland carcinomas, paranasal sinus cancers and melanoma of the head and neck are rare malignancies, these tumors must be treated in specialized anticancer centers with access to the latest surgical and irradiation techniques. Moreover, clinical studies with translational research are needed to identify strong prognostic and predictive factors, and effective molecular-targeted therapies.

Tumeurs malignes de la parotide: prise en charge multidisciplinaire, rôle de la radiothérapie

The low incidence, the wide histological spectrum and the natural, sometimes slow, evolution of malignant parotid gland tumours do not allow to easily establish the impact of their treatments. At present, clinical data come from retrospective cohort analysis, whereas randomized phase II-III trials are confidential. Moreover conclusions from these studies are controversial. We present here the therapeutic highlights of parotid cancers: surgery, with the particular concern of facial nerve preservation; and adjuvant treatment essentially based on radiotherapy. This review focused on adjuvant care explores the indications and the technical aspects of radiation, as well as the role of concurrent chemotherapy.

Phase II Study of Lapatinib in Recurrent or Metastatic Epidermal Growth Factor Receptor and/or erbB2 Expressing Adenoid Cystic Carcinoma and Non–Adenoid Cystic Carcinoma Malignant Tumors of the Salivary Glands

Purpose

Expression of erbB2 and/or epidermal growth factor receptor (EGFR) is associated with biologic aggressiveness and poor prognosis in malignant salivary gland tumors (MSGTs). This phase II study was conducted to determine the antitumor activity of lapatinib, a dual inhibitor of EGFR and erbB2 tyrosine kinase activity, in MSGTs.

Patients and Methods

Patients with progressive, recurrent, or metastatic adenoid cystic carcinoma (ACC) immunohistochemically expressing at least 1+ EGFR and/or 2+ erbB2 were treated with lapatinib 1,500 mg daily, in a two-stage cohort. Patients with non-ACC MSGTs were treated as a separate single-stage cohort.

Results

Of 62 patients screened, 29 of 33 (88%) ACC and 28 of 29 (97%) non-ACC patients expressed EGFR and/or erbB2. Forty patients with progressive disease were enrolled onto the study. Among 19 assessable ACC patients, there were no objective responses, 15 patients (79%) had stable disease (SD), nine patients (47%) had SD ≥ 6 months, and four patients (21%) had progressive disease (PD). For 17 assessable non-ACC patients, there were no objective responses, eight patients (47%) had SD, four patients (24%) had SD ≥ 6 months, and nine patients (53%) had PD. The most frequent adverse events were grade 1 to 2 diarrhea, fatigue, and rash. Eight paired tumor biopsies for correlative studies were procured; results did not correlate with clinical outcome.

Conclusion

Although no responses were observed, lapatinib was well tolerated, with prolonged tumor stabilization of ≥ 6 months in 36% (95% CI, 21% to 54%) of assessable patients. The antitumor effects of lapatinib in MGSTs appear mainly cytostatic, hence evaluation of other molecular targeted agents, or combinations with lapatinib, may be considered. Continued efforts should be made to gain better understanding into the biology of this heterogeneous group of malignancies.

Activity of chemotherapy in the palliative treatment of salivary gland tumors: review of the literature

Chemotherapy is sometimes used as palliation for patients with salivary gland tumors not amenable to curative treatment. However, if chemotherapy improves survival is unknown. To identify some prognostic parameters in this disease, we conducted an extensive review of the literature. The prognostic value of the baseline clinical characteristics and the different chemotherapy regimens used was assessed using the Cox proportional hazards regression model on the available individual data. In addition, the effect of the different chemotherapy drugs on median survival time was evaluated using meta-weighted linear regression with dummy covariates referring to each chemotherapy drug. The total number of patients included in these studies that fit our inclusion criteria was 264 patients. By reviewing carefully the papers and by contacting the different authors, we were able to retrieve the individual data of 205 patients. In the multivariate Cox analysis, only the use of platinum-based chemotherapy was identified as an independent predictor of an increased survival (P = 0.01). These results were confirmed in a meta-analysis where median survival was increased by 2.5 (95% IC:0.7-4.4) and 4.9 (95% IC:0.45-9.4) months for patients treated with platinum (P = 0.007) and anthracyclin-based (P = 0.03) chemotherapy, respectively. Although exploratory, our analysis suggests that treatment with a platinum-based chemotherapy regimen may be an independent factor of better survival for patients with incurable salivary gland neoplasms.

A phase II study of Imatinib for advanced adenoid cystic carcinoma of head and neck salivary glands

Adenoid cystic carcinoma of the salivary glands is characterized by a poor response to chemotherapy. Most cases of adenoid cystic carcinoma express the c-kit protein. Imatinib mesylate (Gleevec) inhibits several protein-tyrosine kinases, including c-kit. We therefore hypothesized that Imatinib may be an effective drug in patients with locally advanced or metastatic adenoid cystic carcinoma and conducted a phase 2 trial in order to study this. Patients with locally advanced or metastatic adenoid cystic carcinoma and c-kit positive tumours were eligible. Fourteen patients were screened and 10 patients (71%) with c-kit positive tumours entered the study. Treatment was begun at a dose of Imatinib of 400mg/day. Dose escalation was allowed in the absence of toxicity. The dose was increased to 600mg/d in three patients and 800mg/d in one patient. Three patients required dose reduction to 300mg/d, due to grade 3 toxicity. No grade 4 toxicity was seen. No objective responses were seen. Two patients (20%) exhibited stable disease for 11 and 14 months, respectively. All other patients stopped treatment after 2-14 (median 6) months due to progressive disease. Imatinib has no major effect on advanced adenoid cystic carcinoma of the head and neck.