The clinicopathological significance of the adipophilin and fatty acid synthase expression in salivary duct carcinoma.

Salivary duct carcinoma (SDC) is an aggressive, uncommon tumor histologically comparable to high-grade mammary ductal carcinoma. SDCs are usually androgen receptor (AR)-positive and often HER2-positive. Recently, therapies targeting these molecules for SDC have attracted attention. Lipid metabolism changes have been described in association with biological behavior in various cancers, although no such relationship has yet been reported for SDC. We therefore analyzed the clinicopathological relevance of the immunohistochemical expression of adipophilin (ADP) and fatty acid synthase (FASN), representative lipid metabolism-related proteins, in 147 SDCs. ADP and FASN were variably immunoreactive in most SDCs (both 99.3%), and the ADP and FASN expression was negatively correlated (P = 0.014). ADP-positive (≥ 5%) SDCs more frequently exhibited a prominent nuclear pleomorphism and high-Ki-67 labeling index than those ADP-negative (P = 0.013 and 0.011, respectively). In contrast, a high FASN score, calculated by the staining proportion and intensity, (≥ 120) was correlated with the high expression of AR and FOXA1 (P < 0.001 and = 0.003, respectively). The ADP and FASN expression differed significantly among the subtypes based on biomarker immunoprofiling, as assessed by the AR, HER2, and Ki-67 status (P = 0.017 and 0.003, respectively). A multivariate analysis showed that ADP-positive expression was associated with a shorter overall and progression-free survival (P = 0.018 and 0.003, respectively). ADP was associated with an aggressive histopathology and unfavorable prognosis, and FASN may biologically interact with the AR signaling pathway in SDC. ADP may, therefore, be a new prognostic indicator and therapeutic target in SDC.

Prognostic Implication of Histopathologic Indicators in Salivary Duct Carcinoma: Proposal of a Novel Histologic Risk Stratification Model.

Salivary duct carcinoma (SDC) is a rare, aggressive malignancy that histologically resembles high-grade mammary duct carcinoma. Because of the rarity of this entity, data verifying the association between histologic features and patient survival are limited. We conducted a comprehensive histologic review of 151 SDC cases and performed an analysis of the association between various histomorphologic parameters and the clinical outcome with the aim of developing a histologic risk stratification model that predicts the prognosis of SDC patients. A multivariate analysis revealed that prominent nuclear pleomorphism (overall survival [OS]: P=0.013; progression-free survival [PFS]: P=0.019), ≥30 mitoses/10 HPF (PFS: P=0.013), high tumor budding (OS: P=0.011; PFS: P<0.001), and high poorly differentiated clusters (OS: P<0.001; PFS: P<0.001) were independent prognostic factors. Patients with vascular invasion demonstrated a marginally significant association with shorter PFS (P=0.064) in a multivariate analysis. We proposed a 3-tier histologic risk stratification model based on the total number of positive factors among 4 prognostically relevant parameters (prominent nuclear pleomorphism, ≥30 mitoses/10 HPF, vascular invasion, and high poorly differentiated clusters). The OS and PFS of patients with low-risk (0 to 1 point) (23% of cases), intermediate-risk (2 to 3 points) (54% of cases), and high-risk (4 points) (23% of cases) tumors progressively deteriorated in this order (hazard ratio, 2.13 and 2.28, and 4.99 and 4.50, respectively; Ptrend<0.001). Our histologic risk stratification model could effectively predict patient survival and may be a useful aid to guide clinical decision-making in relation to the management of patients with SDC.

The high expression of FOXA1 is correlated with a favourable prognosis in salivary duct carcinomas: a study of 142 cases.

AIMS: Salivary duct carcinoma (SDC) is an uncommon, aggressive tumour that, histologically, resembles high-grade mammary ductal carcinoma, and is characterised by the expression of androgen receptor (AR). The androgen signalling pathway, a potential therapeutic target, can be regulated by FOXA1. This study aimed to evaluate the clinicopathological implications of FOXA1 in SDC. METHODS AND RESULTS: We examined the relationship between the immunoexpression of FOXA1 and FOXA1 mutations and clinicopathological factors, including the biomarker status and clinical outcome, in 142 SDCs. FOXA1 was expressed in 128 SDCs (90.1%); the immunoexpression was heterogeneous. SDCs with a higher FOXA1 labelling index (LI) (≥20%) more frequently showed less advanced tumors on T classification (P = 0.002). FOXA1 LI was correlated positively with the AR expression value (r = 0.430, P < 0.001). PI3K and p-mTOR positivity, and intact-PTEN, were associated with a higher FOXA1 LI. Twenty-two of 121 SDCs (18.2%) harboured FOXA1 gene mutations at the flanking regions in and around the forkhead DNA binding domain; however, the given gene mutation and the expression of FOXA1 were not significantly correlated. A multivariate analysis revealed that SDCs with a higher FOXA1 LI were associated with longer overall survival and progression-free survival (P = 0.029 and 0.016, respectively). CONCLUSIONS: In SDC, FOXA1, which may biologically interact with the AR and PI3K signalling pathways, is a putative biomarker that may be associated with a favourable prognosis. Further studies are needed to apply the findings to the development of targeted personalised therapy for patients with SDC.

Chemoradiotherapy With Generic Cisplatin Formulations for Head and Neck Cancers.

The use of generic drugs has been increasing. However, studies of the safety of generic cisplatin (CDDP) for the treatment of head and neck cancer (HNC) have not been reported. This study investigated the treatment completion rates and incidence of CDDP-related adverse events in patients with advanced HNC treated with concurrent chemoradiotherapy (CRT) using generic CDDP. This study included 72 patients who received concurrent CRT using generic CDDP. The number of courses of CDDP was 3 in 45 patients, 2 in 19 patients, and 1 in 8 patients. During 154 courses of 80 mg/m2 generic CDDP, grade 3/4 leukopenia in 21 (14%), neutropenia in 18 (12%), and hypochromia in 8 (5%) cases were reported. Grade 2 elevated serum creatinine occurred in 4 cases (3%), but no grade 3/4 elevated serum creatinine was reported. These results suggest that CRT using generic CDDP is well tolerated in patients with HNC.

Prognostic and histogenetic roles of gene alteration and the expression of key potentially actionable targets in salivary duct carcinomas.

The molecular characteristics of therapeutically-relevant targets and their clinicopathological implications in salivary duct carcinomas (SDCs) are poorly understood. We investigated the gene alterations and the immunoexpression of crucial oncogenic molecules in 151 SDCs. The mutation rates that were identified, in order of frequency, were as follows: TP53, 68%; PIK3CA, 18%; H-RAS, 16%; BRAF, 4%; and AKT1, 1.5%. PIK3CA/H-RAS/BRAF mutations were more common in de novo SDC than in SDC ex-pleomorphic adenoma. Furthermore, these mutations were mutually exclusive for HER2 overexpression/amplification. TP53 mutations were frequently detected in cases with the aberrant p53 expression, and TP53 missense and truncating mutations were associated with p53-extreme positivity and negativity, respectively. DISH analysis revealed no cases of EGFR amplification. The rates of PI3K, p-Akt, and p-mTOR positivity were 34%, 22%, and 66%, respectively; PTEN loss was observed in 47% of the cases. These expressions were correlated according to the signaling axis. Cases with PI3K negativity and PTEN loss appeared to show a lower expression of androgen receptor. In the multivariate analysis, patients with SDC harboring TP53 truncating mutations showed shorter progression-free survival. Conversely, p-Akt positivity was associated with a favorable outcome. This study might provide information that leads to advances in personized therapy for SDC.

Biomarker immunoprofile in salivary duct carcinomas: clinicopathological and prognostic implications with evaluation of the revised classification.

Salivary duct carcinoma (SDC) is an uncommon, aggressive malignant neoplasm histologically resembling high-grade mammary ductal carcinoma. SDC can arise de novo or ex pleomorphic adenoma. To clarify the correlation of biomarker immunoprofile with clinicopathological findings and clinical outcome of SDC, we conducted immunohistochemistry for EGFR, HER2, HER3, AR, CK5/6, p53, and Ki-67, along with HER2 fluorescence in situ hybridization in 151 SDCs. SDCs ex pleomorphic adenoma more commonly overexpressed EGFR, HER2, HER3, and Ki-67 than de novo SDCs (P = 0.015, < 0.001, 0.045, and 0.02, respectively). In multivariate analysis, AR- and CK5/6+ were associated with shorter progression-free survival (P = 0.027 and 0.004, respectively). Moreover, patients with p53-extreme negative/positive demonstrated poorer overall survival (P = 0.007). On assessing the revised classification by the combination of biomarker expression, the percentages of each subtype were as follows: 'apocrine A' (AR+/HER2-/Ki-67-low) (24%), 'apocrine B' (AR+/HER2-/Ki-67-high) (18%), 'apocrine HER2' (AR+/HER2+) (35%), 'HER2-enriched' (AR-/HER2+) (12%), and 'double negative' (AR-/HER2-) (11%). 'Double negative' was further subclassified into 'basal-like' (EGFR and/or CK5/6+) (7%) and 'unclassified' (3%). Consequently, patients with 'apocrine A' showed a better progression-free survival than those with any other subtypes. Our revised immunoprofiling classification was valuable for predicting the survival and might be useful in personalized therapy for patients with SDC.

The efficiency and adverse events of radiotherapy with cetuximab for Japanese head and neck cancer patients.

OBJECTIVES: Radiotherapy with cisplatin (Chemoradiotherapy, CRT) has long been one of the standard treatments for head and neck squamous cell cancer (HNSCC). Approval of cetuximab for the treatment of HNSCC has made radiotherapy with cetuximab (Bioradiotherapy, BRT) a new treatment option for HNSCC. Reports of BRT in the Japanese written in English up to now is only the phase II study, though it includes only 22 patients. Also on the nature of the clinical Phase II trial, sampling bias of cases may exist. Here we report the treatment completion rate, response rate and frequency of adverse events of BRT in Japanese patients with HNSCC in English for the first time. In association with this, we examine the issues related to BRT in Japanese patients. PATIENTS AND METHODS: The subjects consisted of patients with HNSCC who underwent BRT as the first curative treatment (45 cases). Their treatment completion rate, response rate and frequency of adverse events were examined. RESULTS: Of the 45patients, 42 were male and 3 were female. The mean age of the patients was 64 (range from 40 to 86). Adverse events of Grade3 or more were 12 cases (27%) of dermatitis, 31 cases (69%) of mucositis/stomatitis, 6 cases (13%) of interstitial pneumonia. The complication rate of pulmonary emphysema in those who developed interstitial pneumonia and those who did not were 83% and 21%, respectively. The BRT completion rate was 78%, and the response rate was 84%. CONCLUSION: BRT is sufficiently tolerable and have high response rate even for the Japanese, but we should recognize that BRT is not a minimally invasive and easily manageable treatment.

Impact of hematological inflammatory markers on clinical outcome in patients with salivary duct carcinoma: a multi-institutional study in Japan.

The prognostic role of modified Glasgow Prognostic Score (mGPS), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with salivary duct carcinoma (SDC) remains unclear. We conducted a multi-institutional retrospective cohort study of 140 SDC patients. The survival impact of these hematological markers was evaluated using multivariate proportional hazard models.High mGPS (≥1) was significantly associated with worse survival (3-year overall survival (OS): 16.7% vs 66.1%, p-value=0.003; 3-year progression-free survival (PFS): 0.0% vs 27.9%, p-value<0.001). Additionally, high C-reactive protein (CRP) (≥0.39 mg/dl) was significantly associated with worse survival (3-year OS: 32.1% vs 68.2%, p-value=0.001; 3-year PFS: 7.1% vs 31.1%, p-value<0.001). These associations were consistent with multivariate analysis adjusted for established prognostic factors. Although we also found significant association of high NLR (≥2.5) with OS (HR 1.80; 95% confidence interval, 1.05-3.08) in multivariate analysis, this association were inconsistent with the results of PFS. In addition, we found no significant associations of PLR with survival. In conclusion, we found that mGPS, CRP and NLR were identified as prognostic factors associated with survival in SDC patients.