Nivolumab for esophageal squamous cell carcinoma and the predictive role of PD-L1 or CD8 expression in its therapeutic effect

INTRODUCTION

Nivolumab, a programmed death 1 (PD-1) inhibitor, has recently demonstrated efficacy as second-line therapy for esophageal squamous cell carcinoma (ESCC) patients in a phase III trial. We report real-world clinical outcomes of nivolumab therapy for ESCC patients.

METHODS

ESCC patients refractory/intolerant to at least one line of chemotherapy and who received nivolumab as a subsequent line of therapy were included. The efficacy and safety of nivolumab and the predictive role of PD-L1 and CD8 expression were analyzed.

RESULTS

Fifty-eight patients were analyzed for safety and survival outcomes, while 57 were analyzed for objective response rates (ORR) excluding one with no measurable lesions. Eleven patients achieved a partial response, leading to an ORR of 19.3%. The median response duration was 6.5 months (range 4.1-22.4). The median progression-free survival (PFS) and overall survival were 2.1 (95% confidence interval [CI] 1.8-2.3) and 7.4 (95% CI 4.8-10.0) months, respectively. Among patients with adequate samples, 56.9% (29/51), 27.5% (14/51), and 17.6% (9/51) expressed a combined positive score (CPS) ≥ 1, ≥ 10, and ≥ 20, respectively, while 24.4% (11/45) and 57.5% (23/40) were positive for intratumoral and peritumoral CD8 + T cell infiltration, respectively. A significantly longer PFS was observed in patients with a CPS ≥ 20 (7.5 [95% CI 1.8-13.1] vs. 1.9 [1.4-2.3] months, P = 0.05), and a trend towards better survival was seen in those with CPS ≥ 10 or intratumoral CD8 + T cell infiltration.

CONCLUSIONS

Nivolumab is a valuable option at subsequent treatment lines for patients with advanced ESCC.

PDX models of human lung squamous cell carcinoma: consideration of factors in preclinical and co-clinical applications

Background

Treatment of human lung squamous cell carcinoma (LUSC) using current targeted therapies is limited because of their diverse somatic mutations without any specific dominant driver mutations. These mutational diversities preventing the use of common targeted therapies or the combination of available therapeutic modalities would require a preclinical animal model of this tumor to acquire improved clinical responses. Patient-derived xenograft (PDX) models have been recognized as a potentially useful preclinical model for personalized precision medicine. However, whether the use of LUSC PDX models would be appropriate enough for clinical application is still controversial.

Methods

In the process of developing PDX models from Korean patients with LUSC, the authors investigated the factors influencing the successful initial engraftment of tumors in NOD scid gamma mice and the retainability of the pathological and genomic characteristics of the parental patient tumors in PDX tumors.

Conclusions

The authors have developed 62 LUSC PDX models that retained the pathological and genomic features of parental patient tumors, which could be used in preclinical and co-clinical studies.

Trial registration Tumor samples were obtained from 139 patients with LUSC between November 2014 and January 2019. All the patients provided signed informed consents. This study was approved by the institutional review board (IRB) of Samsung Medical Center (2018-03-110)

Characteristics and outcomes of RET-rearranged Korean non-small cell lung cancer patients in real-world practice

OBJECTIVE

Since the first discovery of rearranged during transfection (RET) fusion in lung adenocarcinoma in 2011, two tyrosine kinase inhibitors, namely vandetanib and cabozantinib, are currently available. Despite favorable outcomes in systemic control, the intracranial therapeutic response remains insufficient. In this study, the clinical characteristics and outcomes of non-small cell lung cancer (NSCLC) patients with RET rearrangements were analyzed.

METHODS

Patients with NSCLC harboring RET fusion who received treatment between January 2006 and January 2018 were analyzed. RET rearrangement was identified by FISH or NGS.

RESULTS

A total of 59 patients were identified. About half of the patients were female (47.5%) and never smokers (50.9%). Most patients had adenocarcinoma (89.8%). A total of 17 patients (28.8%) had an intracranial lesion at the initial diagnosis of stage IV disease, and 11 additional patients (18.6%) developed intracranial metastases during follow-up. The median time to development of intracranial metastases was 19.0 months (95% CI: 9.6-28.5), resulting in a >60% cumulative incidence of brain metastasis at 24 months. The systemic efficacy of pemetrexed-based regimens was favorable with progression-free survival of 9.0 (95% CI: 6.9-11.2) and OS of 24.1 (95% CI: 15.2-33.0) months. The median progression-free survival for vandetanib and immunotherapy was 2.9 (95% CI: 2.0-3.8) and 2.1 (95% CI: 1.6-2.6) months, respectively.

CONCLUSIONS

Given the likelihood of RET-rearranged NSCLC progressing to intracranial metastases and the absence of apparent clinical benefit of currently available targeted or immunotherapeutic agents, development of novel treatment with higher selectivity and better penetration of the blood-brain barrier remains a priority.

Osimertinib Improves Overall Survival in Patients With EGFR-Mutated NSCLC With Leptomeningeal Metastases Regardless of T790M Mutational Status

INTRODUCTION

Osimertinib, a third-generation EGFR tyrosine kinase inhibitor, efficiently penetrates the blood-brain barrier. This study explored whether treatment with osimertinib leads to improved overall survival (OS) for patients with EGFR-mutated NSCLC with leptomeningeal metastases (LM) compared with those not treated with osimertinib.

METHODS

From October 2008 to October 2019, patients with EGFR-mutated NSCLC and cytologically confirmed LM were retrospectively analyzed for OS according to osimertinib treatment and T790M mutational status. The OS was defined as the time from the diagnosis of LM to death.

RESULTS

For the 351 patients with LM included in the analysis, the median OS (mOS) was 8.1 months (95% confidence interval [CI]: 7.2-9.0). T790M mutation was detected in 88 of 197 patients tested, and a total of 110 patients were treated with osimertinib after LM. No difference in mOS according to T790M mutational status (10.1 mo [95% CI: 4.31-15.82] versus 9.0 [95% CI: 6.81-11.21], p = 0.936) was found. Nevertheless, patients treated with osimertinib had a superior OS of 17.0 months (95% CI: 15.13-18.94) compared with those not treated with osimertinib who had a mOS of 5.5 months (95% CI: 4.34-6.63), regardless of T790M mutational status (hazard ratio: 0.36 [95% CI: 0.28-0.47], p < 0.001). This was also considerably longer even than the mOS of 8.7 months (95% CI: 7.01-10.39) of those who were never treated with osimertinib but had first- or second-generation EGFR tyrosine kinase inhibitors.

CONCLUSIONS

Osimertinib is a promising treatment option for EGFR-mutated NSCLC with LM regardless of T790M mutational status.

Radial neuropathy caused by intraneural leiomyoma: A case report

INTRODUCTION

Leiomyoma of peripheral nerve is a rare condition characterized by neuropathy of affected nerve. We herein report a rare presentation of leiomyoma of radial nerve which presented with wrist drop.

PATIENT CONCERNS

A 37-year-old man visited our clinic with a history of sudden onset weakness of the wrist dorsiflexion/finger extension of the right side.

DIAGNOSIS

T2-weighted with fat saturation image of MRI demonstrated a well-defined, intra-neural, round mass of about 0.8 cm × 0.5 cm within the radial nerve. Excision of mass established the pathological diagnosis of intra-neural leiomyoma.

INTERVENTIONS

The patient underwent excision of mass and attached nerve tissue, followed his medial antebrachial nerve graft for repair of the defected radial nerve.

OUTCOMES

As of the 1-year follow-up, no symptoms of recurrence have been observed. Also, the strength of wrist dorsiflexion improved to grade 4/5 CONCLUSION:: This rare case demonstrates the importance of MR imaging to differentiate intra-neural leiomyomas from other benign peripheral nerve sheath tumors. Surgical treatment plays an important role in the treatment of patient with intraneural leiomyoma with neurologic deficits.

Deep learning-based immune phenotype analysis reveals distinct resistance pattern of immune checkpoint inhibitor in non-small cell lung cancer

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Background: Resistance pattern and biological mechanism of immune checkpoint inhibitor (ICI) has been poorly understood. Sine suggested resistance mechanisms would be either innate resistance caused by lack of immune recruitment or acquired immune evasion after durable response of ICI treatment, we hypothesized that resistance pattern of tumor microenvironment would be distinct according to duration of ICI response in non-small cell lung carcinoma (NSCLC). In the current study, we applied deep-learning-based classification of three immune phenotypes (3IP): inflamed, excluded, and desert, to objectively assess the immunologic status of tumor microenvironment. Methods: Deep-learning algorithm of H&E Whole-Slide Images (WSI), called Lunit-SCOPE, was trained with 1,824 H&E WSI of NSCLC from Samsung Medical Center (SMC). WSI was divided into patches and each patch (~10 high-power fields) was classified as inflamed, excluded and desert, based on both quantity and localization of immune cells. Among NSCLC patients treated with ICI in SMC, 87 paired treatment-naïve (Pre, patch N = 15,415) and post-progression (Post, patch N = 18,197) tumor tissues were analyzed for Lunit-SCOPE. Results: In 87-paired samples, proportions of excluded and desert phenotypes were increased in post-progression tumor tissues (excluded; Pre 26.8% versus Post 32.5%, desert; Pre 19.5% versus Post 25.3%). Focused on 29 patients classified as inflamed in treatment-naïve, proportion of immune phenotypes of post-progression were clearly different according to duration of response, divided by median progression-free survival (PFS) of 3.7 m. Patients with rapid progression without ICI response (PFS < 3.7 m) turned into desert type (46.2%), whereas durable responder (PFS ≥ 3.7 m) either still remained on inflamed phenotype (42.9%) or turned into excluded phenotype (21.4%). Patients who remained on inflamed phenotype had favorable overall survival after progression on ICI, compared to turned into desert type (median survival not reached versus 6.6 m, P= 0.0296). Conclusions: Resistance patterns of ICI are distinct according to duration of response in patients with inflamed phenotype. Rapid progressor turns off immune into desert phenotype whereas most durable responder keeps immune recruitment into tumor microenvironment, which needs tailored strategy to overcome ICI resistance.

Deep-learning analysis of H&E images to define three immune phenotypes to reveal loss-of-target in excluded immune cells as a novel resistance mechanism of immune checkpoint inhibitor in non-small cell lung cancer

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Background: Discovery of predictive biomarker to enrich the responder of immune checkpoint inhibitor (ICI) in PD-L1-low ( < 50%) non-small cell lung cancer (NSCLC) is still challenging. Recent study showed that loss of heterozygosity (LOH) of HLA led to immune evasion. In the current study, we hypothesized that 3 immune phenotype (3IP): inflamed, excluded and desert would be reliably classified by deep-learning algorithm of H&E image, called Lunit-SCOPE, which would dictate the responder in PD-L1-low NSCLC patients and discover a unique resistance pathway in excluded phenotype. Methods: Lunit-SCOPE was trained with 1,824 H&E Whole-Slide Image (WSI) of NSCLC from Samsung Medical Center (SMC). WSI was divided into patches (~10 high-power fields) which was classified for 3IP, based on both quantity and localization of immune cells. The 3IP was trained and optimized by considering clinical outcome of 119 NSCLC patients with PD-(L)1 inhibitor (training cohort, patches = 25,897), and validated in 62 patients enrolled in LC-biomarker study (NCT03578185, validation cohort, patches = 8,929). Tumor Proportion Score (TPS) of PD-L1 22C3 immunohistochemistry was assessed by pathologists. Tumor Mutational Burden (TMB) was calculated as number of nonsynonymous alterations throughout whole-exome and HLA LOH was called by LOHHLA algorithm. Results: Interactive analysis to classify 3IP in training cohort showed that 8,726 (33.7%), 10,965 (42.3%), and 6,206 (24.0%) patches were classified as inflamed, excluded, and desert, respectively. In validation cohort, median progression-free survival (mPFS) of inflamed phenotype was 10.1 m, significantly prolonged compared to either excluded phenotype (3.0 m, P= 0.0053) or desert phenotype (1.4 m, P= 0.0011). Inflamed phenotype independently dictated favorable ICI outcome in PD-L1-low (TPS < 50%, mPFS of inflamed: 14.3 m vs excluded/desert: 1.4 m, P= 0.0233) as well as in PD-L1-high (TPS≥50%, 10.1 m vs 4.2 m, P= 0.0361), respectively. Excluded phenotype had higher TMB compared to inflamed phenotype had (median 177 vs 107), and HLA LOH was also enriched in excluded phenotype (31.0%) compared to inflamed (17.6%) and desert (16.7%) phenotypes. Conclusions: Lunit-SCOPE based 3IP classification can predict ICI outcome especially in PD-L1-low ( < 50%) patients. Excluded phenotype showed poor ICI outcome even with high TMB, partially explained by HLA LOH resulting in loss-of-target, as a novel resistance mechanism of ICI.

Outstanding clinical efficacy of PD-1/PD-L1 inhibitors for pulmonary pleomorphic carcinoma

BACKGROUND

We evaluated programmed death ligand 1 (PD-L1) expression and efficacy of PD-1/PD-L1 inhibitors in patients with pulmonary pleomorphic carcinoma (PC).

METHODS

We created two cohorts of patients diagnosed with pulmonary PC from 2016 to 2019, PD-L1 expression and programmed death 1 (PD-1)/PD-L1 inhibitor efficacy cohorts. The PD-L1 expression cohort included all patients evaluated for PD-L1 expression, irrespective of PD-1/PD-L1 inhibitor therapy. High PD-L1 expression was defined as ≥50% positive tumour cells (TC) for 22C3, ≥25% for SP263 or ≥10%/5% TC/immune cell (IC) for SP142. The PD-1/PD-L1 efficacy cohort included patients treated with PD-1/PD-L1 inhibitors, irrespective of PD-L1 tests.

RESULTS

One hundred twenty-five of 175 patients diagnosed with pulmonary PCs were included in the PD-L1 expression cohort. Among them, 112 patients (89.6%) had PD-L1-positive (≥1%) tumours and 100 (80.0%) had tumours with high PD-L1 expression. A total of 49 patients were included in the efficacy cohort: 40 received pembrolizumab, 7 nivolumab and 2 atezolizumab. The objective response rate was 49.0%, with a median progression-free survival (PFS) of 7.2 months and a median overall survival of 22.2 months. In the efficacy cohort, high PD-L1 expression (n = 41) was associated with longer PFS (median: 7.2 versus 1.5 months, hazard ratio [HR]: 0.53 [0.22-1.29], p = 0.16) and overall survival (median: 22.2 versus 3.5, HR: 0.21 [0.08-0.57], p = 0.001) than low/negative/unknown PD-L1 expression (n = 8).

CONCLUSION

PD-1/PD-L1 inhibitors show outstanding efficacy for pulmonary PCs, and this is possibly attributable to high PD-L1 expression in these tumours.

Paired genomic analysis of squamous cell carcinoma transformed from EGFR-mutated lung adenocarcinoma

OBJECTIVES

Adenocarcinoma (ADC) to squamous cell carcinoma (SCC) transformation (AST) is reported in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer after tyrosine kinase inhibitor (TKI) failure. However, little is known about the underlying genomic changes during the AST process.

MATERIALS AND METHODS

We retrospectively reviewed our tissue database collected after first- or second- generation EGFR TKI resistance (n = 263) and identified 3 cases of AST. The additional case was acquired from the osimertinib resistance sample. Deep target sequencing (381 genes) using paired samples from 4 patients with AST after EGFR TKI treatment was performed. The histology of each sample was confirmed by TTF-1 and p63 immunohistochemistry. The patients received first- or second-generation EGFR TKI as an initial treatment.

RESULTS

Overall incidence of AST was 1.1% (3/263). Transformed SCC acquired genomic alterations related to the PI3K/AKT/mTOR pathway, in addition to the initial EGFR mutation. In a representative case, two separate sub-clones, with a PTEN nonsense mutation and EGFR p.T790 M mutation, were observed without histologic transformation at the time of gefitinib resistance. After subsequent treatment with osimertinib, SCC transformation was observed with the disappearance of the EGFR p.T790 M mutation and acquired copy number loss in PTEN. Adopting the sub-clonal fraction model elucidates the sub-clonal evolution process of the PTEN mutant sub-clone toward AST under the background of EGFR mutation. The rest of the transformed samples also had acquired genomic alterations in PTEN, LKB1, PIK3CA, or RICTOR, which are related to the PI3K/AKT/mTOR pathway.

CONCLUSIONS

Paired genomic analysis from our sample provides early clinical evidence of the ADC to SCC lineage transition that might be provoked by an alteration in the PI3K/AKT/mTOR pathway during EGFR TKI treatment. This finding could potentially broaden the known spectrum of EGFR TKI resistance mechanisms.

Deep learning-based predictive biomarker for immune checkpoint inhibitor response in metastatic non-small cell lung cancer

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Background: In the era of immunotherapy, immune checkpoint inhibitor (ICI) has changed the treatment paradigm in metastatic non-small cell lung cancer (NSCLC). Along with clinical trials, there is an ongoing investigation to discover the predictive biomarker of ICI which so far has unsatisfactory reliability. As an effort to enhance the predictive value of ICI treatment, we applied deep learning and developed artificial intelligent (AI) score (range from 0 to 1) to analyze the specific context of immune-tumor microenvironment (TME) extracted by scanned images from H&E slides. Methods: As a ground work, deep learning-based H&E image analyzer, Lunit SCOPE, has been trained with H&E images (n = 1824) from ICI naive NSCLC samples. For the calculation of AI score, training was conducted using responder/non-responder labeled ICI treated samples from the exploratory cohort. The ICI responder was defined as the patient with a best overall response of partial or complete response and stable disease for more than 6 months. The positivity of PD-L1 immunohistochemistry (IHC) was assessed manually by pathologists. Results: The exploratory cohort is composed of NSCLC patients treated with ICI (n = 189) in Samsung Medical Center, and response to ICI was observed in 72 (38.1%) patients. Median follow-up duration was 6.8 months (6.6~8.2). Samples with PD-L1 IHC positive, defined by ≥ 1%, was observed in 138 (73.0%) patients. AI score was significant higher in the responder group (median: 0.391 vs 0.205, P = 6.14e-5), and the patients with AI score above the cut-off (0.337) showed a better response to ICI (odds ratio [OR] 3.47 P = 7.34e-5) which is higher than patients with PD-L1 ≥ 1% (OR 1.92, P = 0.069). High AI score group (n = 83) showed significantly favorable PFS compared to low AI score group (n = 106, median PFS: 5.1m vs 1.9m, hazard ratio [HR] 0.51, P = 9.6e-5) and this outcome was independent with PD-L1 status (P = 6.0e-5). In subgroup analysis, PFS of PD-L1 high / AI score high group (n = 63) had longer median PFS (6.7m) compared to both PD-L1 high / AI score low group (n = 70, 4.0m, P = 0.001) and PD-L1 low/AI score low group (n = 35, 1.9m, P = 4.0e-6). Tumor infiltrating lymphocyte (TIL) density of cancer epithelium was significantly correlated with AI score (Pearson’s r = 0.310, P = 1.43e-5), which suggests that AI score may partly reflect TME represented by TIL. Conclusions: The AI score by machine-learned information, extracted from H&E images without additional IHC stain, could predict responsiveness and PFS of ICI treatment independent of PD-L1 IHC positivity.

Paired whole exome and transcriptome analyses for the Immunogenomic changes during concurrent chemoradiotherapy in esophageal squamous cell carcinoma

BACKGROUND

The immunogenomic changes triggered by concurrent chemoradiation therapy (CCRT), a standard neoadjuvant treatment for locally advanced esophageal squamous cell carcinoma (ESCC), are unknown. We aimed to analyze the early immunogenomic changes in ESCC induced by CCRT and to correlate them with clinical outcomes.

METHODS

We collected biopsy samples from 40 patients with ESCC and the surgical candidates were treated with 5-fluorouracil (5-FU)/Cisplatin and concurrent radiation therapy. Endoscopic biopsy was performed before and after one treatment cycle of 5-FU/Cisplatin and 5 to 18 fractions of radiation. We analyzed immunogenomic changes using paired whole-exome sequencing (n = 29) and paired whole-transcriptome sequencing (WTS, n = 23). Multiplex immunohistochemistry (IHC) was conducted in four representative pair samples.

RESULTS

Fourteen out of 23 WTS samples (60.8%) showed increased immune scores after CCRT, as calculated by ESTIMATE. The rate of progression-free survival was higher in patients with increased immune scores compared with the remaining patients (83.1% vs. 57.1%, p = 0.25). Tumor mutation burden and neoantigen load were significantly reduced after CCRT (p < 0.001). We observed no specific correlation with non-synonymous mutations and no changes in the single-nucleotide variant spectrum after CCRT. Post-CCRT samples were enriched in gene sets related to immune signaling pathways, such as interferon gamma signaling and CD28 co-stimulation. Multiplex IHC showed an incremental trend in the proportion of CD4 positive cells in cytokeratin positive region after CCRT. However, CD8, CD20, FOXP1, PD-L1 showed no definitive trend. Proportion of immune cells calculated by CIBERSORT, showed that significant increase in neutrophils after CCRT.

CONCLUSIONS

We have comprehensively analyzed the early immunogenomic changes induced in ESCC by CCRT and correlated them with clinical outcomes. Our results provide a potential basis for combining immunotherapy with CCRT for the treatment of ESCC.

Efficacy and Safety of Lorlatinib in Korean Non-Small-Cell Lung Cancer Patients With ALK or ROS1 Rearrangement Whose Disease Failed to Respond to a Previous Tyrosine Kinase Inhibitor

INTRODUCTION

Non-small-cell lung cancer (NSCLC) patients harboring ALK or ROS1 rearrangements invariably acquire resistance to the first- and second-generation tyrosine kinase inhibitors (TKIs), most notably ALK G1202R and ROS1 G2032R. Lorlatinib, a novel third-generation TKI, produced remarkable results from the first-in-man phase 1 trial: an overall response rate of 46% and 50% for previously treated ALK- and ROS1-positive patients, respectively. However, the efficacy of lorlatinib has not been widely validated in Asian patients.

PATIENTS AND METHODS

Patients with advanced NSCLC with ALK or ROS1 rearrangements who initiated lorlatinib therapy between November 2016 and July 2018 were retrospectively analyzed.

RESULTS

Twelve consecutive patients were included. The median age was 55 years (range, 36-76 years). Ten (83%) had ALK-positive NSCLC and 2 (17%) had ROS1-positive NSCLC. All patients had a history of first- or second-generation ALK TKI receipt. Two ALK-positive patients and one ROS1-positive patient had the G1202R and G2032R mutations, respectively. The overall response rate was 64% and the disease control rate was 91%. Of the 3 ALK-positive patients with intracranial target lesions, 1 (33%) had a complete response and 2 (67%) a partial response, producing an intracranial objective response of 100%. The median progression-free survival was 6.5 months (range, 1.0-16.5 months). The most common adverse event was hypercholesterolemia (83%), and no adverse event-related dose reductions or treatment discontinuations were reported.

CONCLUSION

This study is the first to report that lorlatinib is an important novel therapeutic option for Asian patients who have advanced NSCLC harboring ALK/ROS1 mutations whose disease progressed during treatment with first- and second-generation TKIs.

Anaplastic lymphoma kinase (ALK)-expressing Lung Adenocarcinoma with Combined Neuroendocrine Component or Neuroendocrine Transformation: Implications for Neuroendocrine Transformation and Response to ALK-tyrosine Kinase Inhibitors

BACKGROUND

Anaplastic lymphoma kinase tyrosine kinase inhibitors (ALK-TKIs) are usually effective in lung adenocarcinoma patients with anaplastic lymphoma kinase (ALK) rearrangement. However, even after a good response to ALK-TKI therapy, most patients acquire resistance to these agents. Histological transformation is one of several suggested mechanisms of acquired resistance to ALK-TKIs. The clinicopathologic features of four patients with ALK-expressing adenocarcinoma and neuroendocrine features were analyzed.

METHODS

We selected combined neuroendocrine differentiation in pulmonary adenocarcinoma cases with positive ALK immunostaining. Neuroendocrine differentiation was confirmed by CD56 immunohistochemical stain. Additional ALK fluorescence in situ hybridization (FISH) study and epidermal growth factor receptor (EGFR) mutation tests were also performed.

RESULTS

All four cases were positive for ALK immunohistochemistry and no EGFR mutations were detected. Interestingly, the results of ALK FISH assays showed rearrangement in only two cases. Three cases showed combined adenocarcinoma and neuroendocrine component without history of ALK-TKI administration; one of them was treated with crizotinib and experienced partial tumor regression. The remaining case had an adenocarcinoma at initial biopsy and she showed a partial response to crizotinib, and neuroendocrine changes were visible on second biopsy. Then she was treated with ceritinib and achieved a partial response.

CONCLUSION

We suggest that ALK-rearranged adenocarcinoma with combined neuroendocrine component is responsive to ALK-TKIs. Moreover, even after neuroendocrine transformation as a result of resistance to ALK-TKIs, the tumor may have partial response to second generation ALK-TKIs.

Clinicopathologic characteristics of EGFR, KRAS, and ALK alterations in 6,595 lung cancers

BACKGROUND

EGFR, KRAS, and ALK alterations are major genetic changes found in non-small cell lung cancers (NSCLCs). Testing advanced lung adenocarcinoma tumors for these three genes is now standard care. The purpose of this study was to investigate the clinicopathologic expression pattern of these three genes in East Asian NSCLC patients.

PATIENTS AND METHODS

We conducted a retrospective study of all patients tested for mutations of these three genes at a single institute in Korea between 2006 and 2014. Study data were extracted from electronic medical records. Univariate and multivariate logistic regression analyses were used to measure associations between clinicopathologic features and alterations of EGFR, KRAS, and ALK.

RESULTS

We detected 12 EGFR-mutated tumors with additional mutations in KRAS (N=6, 0.1%) or ALK (N=6, 0.1%). General clinicopathologic characteristics of tumors with EGFR, KRAS, or ALK mutations were similar to previous reports. Patients having EGFR L858R point mutations were older than patients having EGFR exon 19 deletions. EGFR G719X point mutations were more common in men and smokers than exon 19 deletions or L858R point mutations. Tumors having KRAS G12C mutations were less often of mucinous type than those with G12D or G12V, mutations.

CONCLUSIONS

This is the largest three gene molecular epidemiology study in East Asian NSCLC patients. Each genetic alteration was associated with distinct clinicopathologic characteristics. Furthermore, different age and sex are associated with different subtypes of EGFR and KRAS mutations.

Phenylethanolamine N-methyltransferase downregulation is associated with malignant pheochromocytoma/paraganglioma

Malignant pheochromocytoma/paraganglioma (PCC/PGL) is defined by the presence of metastases at non-chromaffin sites, which makes it difficult to prospectively diagnose malignancy. Here, we performed array CGH (aCGH) and paired gene expression profiling of fresh, frozen PCC/PGL samples (n = 12), including three malignant tumors, to identify genes that distinguish benign from malignant tumors. Most PCC/PGL cases showed few copy number aberrations, regardless of malignancy status, but mRNA analysis revealed that 390 genes were differentially expressed in benign and malignant tumors. Expression of the enzyme, phenylethanolamine N-methyltransferase (PNMT), which catalyzes the methylation of norepinephrine to epinephrine, was significantly lower in malignant PCC/PGL as compared to benign samples. In 62 additional samples, we confirmed that PNMT mRNA and protein levels were decreased in malignant PCC/PGL using quantitative real-time polymerase chain reaction and immunohistochemistry. The present study demonstrates that PNMT downregulation correlates with malignancy in PCC/PGL and identifies PNMT as one of the most differentially expressed genes between malignant and benign tumors.

PIK3CA amplification is associated with poor prognosis among patients with curatively resected esophageal squamous cell carcinoma

To investigate the clinicopathologic characteristics and the prognostic impact of PIK3CA gene amplification in curatively resected esophageal squamous cell carcinoma (ESCC). Using 534 curatively resected ESCCs, the PIK3CA gene copy number was evaluated with fluorescent in situ hybridization. PIK3CA amplification was defined as PIK3CA/centromere 3 ratio is ≥ 2.0 or average number of PIK3CA signals/tumor cell nucleus ≥ 5.0. PIK3CA mutations in exon 9 and 20, encoding the highly conserved helical and kinase domains were assessed by direct sequencing in 388 cases. PIK3CA amplification was detected in 56 (10.5%) cases. PIK3CA amplification was significantly associated with higher T-stage (P=0.026) and pathologic stage (P=0.053). PIK3CA amplification showed a significantly shorter disease free survival (DFS) compared with that of non-amplified group (33.4 vs 63.1 months, P=0.019). After adjusting for gender, tumor location, pathologic stage, histologic grade and adjuvant treatment, PIK3CA amplification was significantly associated with a shorter DFS (adjusted hazard ratio [AHR] 1.53; 95% CI, 1.10-2.17; P=0.02). Though the statistical insignificance, PIK3CA amplification showed tendency of shorter OS (52.1 vs 96.5 moths, P=0.116). PIK3CA mutations were detected in 6 (1.5%) of 388 cases; 5 cases with exon 9 mutations in E545K while one exon 20 mutation in H1047L. PIK3CA amplification is a frequent oncogenic alteration and associated with shorter survival, suggesting its role as a prognostic biomarker in resected ESCC. PIK3CA amplification may represent a promising therapeutic target for ESCC.

Open-Label, Multicenter, Phase II Study of Ceritinib in Patients With Non-Small-Cell Lung Cancer Harboring ROS1 Rearrangement

Purpose ROS1 rearrangement is a distinct molecular subset of non-small-cell lung cancer (NSCLC). We investigated the efficacy and safety of ceritinib in patients with ROS1-rearranged NSCLC. Patients and Methods We enrolled 32 patients with advanced NSCLC who tested positive for ROS1 rearrangement by fluorescent in situ hybridization. Ceritinib 750 mg was administered once daily. The primary end point was objective response rate. The secondary end points were disease control rate; duration of response; progression-free survival; overall survival; toxicity; and concordance among fluorescent in situ hybridization, immunohistochemistry, and next-generation sequencing. Results Between June 7, 2013, and February 1, 2016, 404 patients underwent ROS1 prescreening, and 32 patients with ROS1 rearrangement were enrolled. All patients except two were crizotinib-naïve. At the time of data cutoff, the median follow-up was 14.0 months, and 18 patients (56%) had discontinued treatment. Of the 32 patients enrolled, 28 were evaluable for response by independent radiologic review. Objective response rate was 62% (95% CI, 45% to 77%), with one complete response and 19 partial responses; duration of response was 21.0 months (95% CI, 17 to 25 months); and disease control rate was 81% (95% CI, 65% to 91%). The median progression-free survival was 9.3 months (95% CI, 0 to 22 months) for all patients and 19.3 months (95% CI, 1 to 37 months) for crizotinib-naïve patients. The median overall survival was 24 months (95% CI, 5 to 43 months). Of the eight patients with brain metastases, intracranial disease control was reported in five (63%; 95% CI, 31% to 86%). The most common adverse events (majority, grade 1 or 2) for all treated patients were diarrhea (78%), nausea (59%), and anorexia (56%). Conclusion Ceritinib demonstrated potent clinical activity in patients with ROS1-rearranged NSCLC who were heavily treated previously with multiple lines of chemotherapy.

Identification of leukocyte-specific protein 1-positive cells: a clue to the cell of origin and a marker for the diagnosis of dermatofibroma

Background

Dermatofibroma (DF) comprises a heterogeneous group of mesenchymal tumors, with fibroblastic and histiocytic elements present in varying proportions. The cell of origin of DF has been investigated, but remains unclear.

Objective

The present study attempted to investigate the expression of leukocyte-specific protein 1 (LSP1), a marker of fibrocytes, in DF. Additionally, we evaluated the effectiveness of LSP1 in the differential diagnosis of DF from dermatofibrosarcoma protuberans (DFSP).

Methods

Immunohistochemical staining was performed on 20 cases of DF using antibodies against LSP1, CD68, and factor XIIIa (FXIIIa). In addition, the expression of LSP1 and FXIIIa was evaluated in 20 cases of DFSP.

Results

Eighteen of 20 cases (90%) of DF stained positive for LSP1, with variation in the intensity of expression. CD68 was positive in 10 cases (50%), and FXIIIa was expressed in all cases of DF. There were differences between the regional expression patterns of the three markers in individual tumors. In contrast, only 2 of 20 cases of DFSP expressed LSP1, and none of DFSP cases stained positive for FXIIIa.

Conclusion

The LSP1-positive cells in DF could potentially be fibrocyte-like cells. FXIIIa and CD68 expression suggests that dermal dendritic cells and histiocytes are constituent cells of DF. It is known that fibrocytes, dermal dendritic cells and histiocytes are all derived from CD14+ monocytes. Therefore, we suggest that DF may originate from CD14+ monocytes. Additionally, the LSP1 immunohistochemical stain could be useful in distinguishing between DF and DFSP.

Efficacy of pazopanib monotherapy in patients who had been heavily pretreated for metastatic soft tissue sarcoma: a retrospective case series

Background

We retrospectively reviewed outcomes of treatment with pazopanib, an oral multi-tyrosine kinase angiogenesis inhibitor, in patients with advanced soft tissue sarcoma, a rare and heterogeneous tumor group with limited treatment options.

Methods

Between 2009 and 2013, 43 patients with metastatic soft tissue sarcoma received pazopanib as salvage chemotherapy after one or more cytotoxic regimens. Response rate, progression-free survival, and overall survival were analyzed according to histological subtype, Eastern Cooperative Oncology Group performance status, and metastatic site.

Results

Common histological subtypes included leiomyosarcoma (n = 9), angiosarcoma (n = 6), malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma (MFH/UPS, n = 5), malignant peripheral nerve sheath tumor (MPNST, n = 5), and synovial sarcoma (n = 4). Nineteen patients (44.2%) received more than two chemotherapy regimens before pazopanib. At the time of analysis, 208 treatment cycles of pazopanib had been administered (median, 4.8 cycles per patient), and no treatment-related mortality occurred. The disease control rate was 61.0% (95% confidence interval [CI], 46.1–75.9%), and the overall response rate was 17.1% (partial response, n = 7; complete response, n = 0). Partial response was achieved in two patients with synovial sarcoma, two with MFH/UPS, one with MPNST, one with leiomyosarcoma, and one with angiosarcoma. The median lengths of progression-free survival and overall survival were 5.0 months (95% CI, 3.6–6.4 months) and 8.2 months (95% CI, 5.8–10.6 months), respectively. Progression-free survival was shorter in the patients with liposarcoma and rhabdomyosarcoma (1.3 and 0.9 months, respectively) than in those with leiomyosarcoma, MPNST, MFH/UPS, and synovial sarcoma (5.6, 6.5, 7.1, and 7.7 months, respectively).

Conclusions

Pazopanib demonstrated acceptable antitumor activity in the Asian patients who had been heavily pretreated for sarcoma, with seemingly more favorable results in the patients with leiomyosarcoma, MPNST, MFH/UPS, and synovial sarcoma than in those with liposarcoma and rhabdomyosarcoma.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1160-x) contains supplementary material, which is available to authorized users.

Successful use of pazopanib for treatment of refractory metastatic hemangiopericytoma

Hemangiopericytoma is a rare disease entity of soft-tissue sarcoma (STS) that can be cured with surgical resection. In cases of inoperable recurrence or metastasis, palliative chemotherapy is indicated, though there is currently no approved chemotherapy regimen. Therefore new treatment regimens are needed.

We describe three cases of metastatic hemangiopericytoma. In the first case, five lines of chemotherapeutic agents were used unsuccessfully in a patient with a 12-year history of metastatic hemangiopericytoma. After one cycle of pazopanib therapy, however, chest radiography showed a decrease in tumor volume of more than 30%. A marked decrease in FDG uptake on PET CT was also noted, and the patient is now on her 5^th month of pazopanib therapy. The second case is a patient with a brain hemangiopericytoma with multiple liver, lung, and bone metastases. Pazopanib induced radiologic stabilization of metastatic disease over the course of 8 months. The third case is a patient with a retroperitoneal hemangiopericytoma with pleural and peri-renal metastases. For more than 8 months, he has exhibited stable disease with pazopanib treatment.

Pazopanib may be useful for treatment of metastatic hemangiopericytoma, though further studies are needed to confirm the efficacy of this medication and to investigate its molecular mechanism of action.

Role of HER3 expression and PTEN loss in patients with HER2-overexpressing metastatic breast cancer (MBC) who received taxane plus trastuzumab treatment

BACKGROUND

The aim of this study was to investigate the role of human epidermal growth factor receptor (HER3) and PTEN expression in patients with HER2-overexpressing metastatic breast cancer (MBC).

METHODS

One hundred twenty-five MBC patients who were treated with taxane plus trastuzumab chemotherapy as first-line therapy were included in this analysis. Immunohistochemical (IHC) staining with HER3 and PTEN antibodies were conducted retrospectively.

RESULTS

Patients who had negative HER3 staining (62.4%) had a better progression-free survival (PFS) than did those who had positive HER3 staining (P=0.001; median PFS, 21 vs 11 months). Patients who had a PTEN score >20 (78.1%) showed longer PFS than did those with a PTEN score ≤20 (P=0.006; median PFS, 13 vs 9 months). Patients who had a PTEN score >20 exhibited a longer overall survival (OS) than did those with a PTEN score ≤20 (P=0.005; median OS, 48 vs 25 months). HER3 negativity and PTEN loss were identified as independent risk factors for PFS. PTEN loss was identified as an independent risk factor for OS.

CONCLUSION

HER3 and PTEN expressions may be predictive markers, and PTEN expression may be a predictive and prognostic biomarker for trastuzumab treatment in HER2-positive MBCs.

A phase-1b study of everolimus plus paclitaxel in patients with small-cell lung cancer

BACKGROUND

The mammalian target of rapamycin (mTOR) pathway is dysregulated in small-cell lung cancer (SCLC) and everolimus is an oral mTOR inhibitor.

METHODS

This phase-1b study assessed everolimus safety at the levels of 2.5, 5, or 10 mg once daily in combination with paclitaxel (175 mg m(-2)) once every 3 weeks in previously treated SCLC patients. The primary end point was to determine the maximum tolerated dose of everolimus.

RESULTS

Among 21 enrolled patients, common drug-related adverse events were anaemia, neutropenia, thrombocytopenia, pain, hyperglycemia, and stomatitis. Out of 11 evaluable patients treated with everolimus at the level of 5 mg, 1 patient experienced dose-limiting toxicity (DLT) of grade 4 febrile neutropenia and grade 3 thrombocytopenia. The other two DLTs (grade 4 thrombocytopenia and grade 3 hyperglycemia) occurred in two out of three patients receiving everolimus 10 mg. The overall objective response rate was 28%.

CONCLUSION

Everolimus showed an acceptable safety profile and preliminary antitumour activity at the dose of 5 mg once daily when combined with 3-weekly paclitaxel 175 mg m(-2) in patients with SCLC.

Prediction of disease-free survival in hepatocellular carcinoma by gene expression profiling

BACKGROUND

Progression of hepatocellular carcinoma (HCC) often leads to vascular invasion and intrahepatic metastasis, which correlate with recurrence after surgical treatment and poor prognosis. The molecular prognostic model that could be applied to the HCC patient population in general is needed for effectively predicting disease-free survival (DFS).

METHODS

A cohort of 286 HCC patients from South Korea and a second cohort of 83 patients from Hong Kong, China, were used as training and validation sets, respectively. RNA extracted from both tumor and adjacent nontumor liver tissues was subjected to microarray gene expression profiling. DFS was the primary clinical end point. Gradient lasso algorithm was used to build prognostic signatures.

RESULTS

High-quality gene expression profiles were obtained from 240 tumors and 193 adjacent nontumor liver tissues from the training set. Sets of 30 and 23 gene-based DFS signatures were developed from gene expression profiles of tumor and adjacent nontumor liver, respectively. DFS gene signature of tumor was significantly associated with DFS in an independent validation set of 83 tumors (P = 0.002). DFS gene signature of nontumor liver was not significantly associated with DFS in the validation set (P = 0.827). Multivariate analysis in the validation set showed that DFS gene signature of tumor was an independent predictor of shorter DFS (P = 0.018).

CONCLUSIONS

We developed and validated survival gene signatures of tumor to successfully predict the length of DFS in HCC patients after surgical resection.

HER3 status by immunohistochemistry is correlated with poor prognosis in hormone receptor-negative breast cancer patients

Breast cancer is a highly heterogeneous malignancy. The triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER2) breast cancer subtypes are highly aggressive and are associated with a poor prognosis. The therapeutic targets for TNBC remain undefined, and many patients with the HER2 subtype acquire resistance to therapy after prolonged treatment. The objective of this study was to evaluate the prognostic significance of HER3 expression in invasive breast carcinoma. We established matched tissue microarray (TMA) blocks and clinical data from 950 cases of invasive breast carcinoma with long-term clinical follow-up data (median 109.7 months). Using the TMAs, we characterized the expression of ER, PR, HER2, EGFR, and HER3 by immunohistochemistry. Each case was classified as one of four IHC-based subtypes based on the expression of hormonal receptor (HR) and HER2. The clinicopathological characteristics and survival of 950 patients were analyzed by subtype. In the TNBC subtype, the HER3(+) group showed poorer disease-free survival (DFS, P = 0.010) and overall survival (OS, P = 0.015) than the HER3(-) group. In the HER2 subtype, the HER3(+) group also showed poorer DFS (P = 0.022) and OS (P = 0.077) than the HER3(-) group. However, there was no difference in patients with HR-positive breast cancer. HER3 expression was associated with poor DFS in both the TNBC and HER2 subtypes and poor OS in the TNBC subtype. HER3 overexpression is an important prognostic marker in hormone receptor-negative breast cancer, and further study is needed to clarify the role of HER-3 targeted treatment.

A proposal for creating a guideline for cancer registration of the fibromatosis, PEComa group, malignant lymphoma In Situ and dendritic cell tumors (III)

BACKGROUND

Understanding the biologic behavior of a tumor is a prerequisite for tumor registration code assignment. The aim of this report was to propose appropriate behavior codes of the International Classification of Disease Oncology 3 (ICD-O3) to rare, yet pathologically interesting hematopoietic and soft tissue tumors.

METHODS

The Study Group for Hematopathology, the Bone and Soft Tissue Pathology Study Group, and the Cancer Registration Committee prepared the questionnaire containing provisional behavior codes of selected diseases.

RESULTS

In situ lesions of mantle cell and follicular lymphomas, dendritic cell tumors, and neoplasms with perivascular epithelioid cell differentiation (PEComa), not otherwise specified were classified as malignant (-/3). The fibromatosis group, with the exception of lipofibromatosis, was proposed as benign (-/0). Lipofibromatosis and several diseases that belong to the PEComa group were proposed as uncertain malignant potential (-/1). For the hematologic and soft tissue tumors, 274 and 288 members of the Korean Society of Pathologists, respectively, provided opinions through questionnaire, and most responders showed agreement with the provisional behavior code proposed.

CONCLUSIONS

The determination of behavior codes for the rare diseases described in this study, especially those of the PEComa group or malignant lymphoma, could be viewed as impractical and premature, but this study provides the basis for future research on this topic.

Primary extraskeletal osteosarcoma of the seminal vesicle: a case report and literature review

A primary extraskeletal osteosarcoma (EOS) is a rare tumour. An EOS of the seminal vesicle has not been reported in the literature. We describe a case of a seminal vesicle EOS initially detected as a pre-rectal mass on a routine transrectal ultrasound in a 48-year-old man. A computed tomography (CT) scan confirmed the tumour to be arising from the left seminal vesicle. A robot-assisted laparoscopic seminal vesiculectomy was performed to avoid neurovascular bundle injury. Microscopic examination of the resected specimen showed a poorly differentiated osteosarcoma originating from the seminal vesicle. The patient received adjuvant chemotherapy. He is doing well without voiding or erectile dysfunction and he is tumour-free five months after surgery.

Thymidylate synthase and thymidine phosphorylase as predictive markers of capecitabine monotherapy in patients with anthracycline- and taxane-pretreated metastatic breast cancer

PURPOSE

The primary purpose of this study was to evaluate the role of thymidylate synthase (TS) and thymidine phosphorylase (TP) as biomarkers to predict clinical outcomes of capecitabine monotherapy in patients with anthracycline- and taxane-pretreated metastatic breast cancer (MBC).

METHODS

Of the patients who were previously treated with anthracycline and taxane regimens, 90 patients who had available tissue block for immunohistochemistry with measurable lesions were included. All patients received capecitabine (2,500 mg/m(2)/day) for 14 days every 3 weeks.

RESULTS

High TS expression was more common among patients with triple-negative (TN) subtype than among patients with other subtypes (33% for hormone receptor+, 8% for HER2+, and 58% for TN, P = 0.023). The median PFS was significantly lower in patients with high TS (6.6 vs. 3.0 months; P = 0.017) and low TP expressions (6.0 vs. 3.3 months; P = 0.013). A high TS and a low TP expressions were identified as unfavorable independent risk factors for PFS to capecitabine monotherapy in multivariate analysis (hazard ratio [HR], 1.7, P = 0.037 for high TS score; HR, 1.8, P = 0.014 for low TP score).

CONCLUSIONS

Our data suggest that high TS and low TP scores correlate with a shorter PFS for capecitabine monotherapy in patients with anthracycline- and taxane-pretreated MBC.

Favorable response to doxorubicin combination chemotherapy does not yield good clinical outcome in patients with metastatic breast cancer with triple-negative phenotype

BACKGROUND

We analyzed the responses to first line treatment and clinical outcomes of metastatic breast cancer patients treated with palliative doxorubicin/cyclophosphamide (AC) according to molecular cancer subtype.

METHODS

A retrospective analysis was performed for 110 metastatic breast cancer patients selected on the basis of palliative AC treatment and the availability of immunohistochemical data for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2/neu) status.

RESULTS

Of the 110 patients analyzed, 71 (64.5%) were hormone receptor positive (HR+), 14 (12.7%) were HER2+, and 25 (22.7%) were triple negative (TN). There were no differences in age, stage at diagnosis, total number of cycles of palliative chemotherapy, incidence of visceral metastasis, and metastatic sites with the exception of liver among breast cancer subtypes. The overall response rates to AC were 55.9% for the HR+ subgroup, 42.9% for the HER2+ subgroup, and 56.5% for the TN subgroup. The progression-free survival (PFS) in patients with HER2+ and TN were significantly shorter than in the HR+ (median PFS, 9.1 vs 8.1 vs 11.5 months, respectively; p = 0.0002). The overall survival (OS) was 25.4 months in the TN subgroup and 27.3 months in HER2+ subgroup. The median OS for these two groups was significantly shorter than for patients in the HR+ subgroup (median, 38.5 months; 95% CI, 30.1-46.9 months; p < 0.0001).

CONCLUSIONS

The response to palliative AC chemotherapy did not differ among breast cancer subtypes. Despite chemosensitivity for palliative AC, the TN subtype has a shorter overall survival than non-TN subtypes. Innovative treatment strategies should be developed to slow the course of disease.

Clinical presentation of carcinoma of unknown primary: 14 years of experience

A carcinoma of unknown primary (CUP) is a histologically confirmed metastatic cancer without a definitive primary site after performing a detailed medical examination. The purpose of the study was to classify unfavorable CUPs into more reliable disease entities, which reflect the clinical course. We reviewed the medical records of patients diagnosed with a CUP between January 1995 and March 2008. Patients were classified into a conventional favorable-risk group and a newly proposed unfavorable-risk group according to the clinicopathologic features. Five hundred eighty-six patients were diagnosed with CUPs. Fifty-six (9.6%) patients were classified in the conventional favorable-risk group, and 486 (82.9%) patients were classified in the unfavorable-risk group. We further classified the 486 patients into six subgroups with an unfavorable risk, while excluding 29 patients (5.0%) who were not classifiable. The overall survival of the conventional favorable-risk group was 47.0 months (95% CI, 11.1~82.9 months), which was significantly longer than that of any subgroup of the newly proposed unfavorable-risk group (P < 0.001). Patients with squamous cell carcinoma in the abdominopelvic cavity showed similar overall survival with unfavorable-risk group (P = 0.484). Women with non-papillary malignant ascites had a survival in between the favorable and unfavorable groups (P <  0.001). The newly proposed unfavorable-risk group may assist in classifying CUP patients with an unfavorable risk in a clinically more meaningful way. Squamous cell carcinoma in the abdominopelvic cavity should be considered in the unfavorable-risk group and women with non-papillary malignant ascites in an intermediate-risk group. Further studies with molecular profiling would help in classifying and treating patients with CUPs and an unfavorable risk.

A risk stratification by hormonal receptors (ER, PgR) and HER-2 status in small (< or = 1 cm) invasive breast cancer: who might be possible candidates for adjuvant treatment?

As the use of screening mammography expands, the proportion of invasive breast cancer > or = 1 cm is increasing. The aims of this study were: (1) to identify risk factors for systemic metastases in patients with > or = 1 cm invasive breast cancer and (2) to investigate the patient groups at the greatest risk for metastases with such small tumors. Data were collected retrospectively from the breast cancer registry of our institution for patients with invasive breast cancer from October 1994 to December 2004. Of 4,036 patients who received curative breast cancer surgery, we identified 427 patients who had T1a or T1b breast cancer excluding 39 patients who received neoadjuvant chemotherapy. Ipsilateral axillary lymph node involvement was found in 13% (57/427) of patients at the time of surgery. A multivariate analysis was conducted in 370 (T1aN0, T1bN0) patients without lymph node involvement. In a Cox-regression model, HER-2 positive and triple negative (TN) groups were identified as independent risk factors to predict distant relapse-free survival (DRFS) [Hazard ratio (HR) 8.8, P = 0.003 for HER-2 positive group; HR 5.1, P = 0.026 for TN group] in T1bN0 tumors. Statistical significance was not maintained when the analysis was limited to T1aN0 tumors. Even though T1aN0 and T1bN0 tumors have a relatively low risk of systemic failure, antiHER-2-directed therapy for HER-2 group and new innovative adjuvant systemic treatment for TNBC patients with T1bN0 tumors should be considered. Prospective adjuvant trials are warranted in these subgroups of patients.

Liver X receptor mediates hepatitis B virus X protein-induced lipogenesis in hepatitis B virus-associated hepatocellular carcinoma

Although hepatitis B virus X protein (HBx) has been implicated in abnormal lipid metabolism in hepatitis B virus (HBV)-associated hepatic steatosis, its underlying molecular mechanism remains unclear. Liver X receptor (LXR) plays an important role in regulating the expression of genes involved in hepatic lipogenesis. Here we demonstrate that LXRalpha and LXRbeta mediate HBV-associated hepatic steatosis. We have found that HBx induces the expression of LXR and its lipogenic target genes, such as sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and peroxisome proliferator-activated receptor, and this is accompanied by the accumulation of lipid droplets. RNA interference with LXR expression decreases the amount of lipid droplets as well as the expression of the lipogenic genes, and this indicates that HBx-induced lipogenesis is LXR-dependent. LXRalpha and HBx colocalize in the nucleus and are physically associated. HBx induces the transactivation function of LXRalpha by recruiting CREB binding protein to the promoter of the target gene. Furthermore, we have observed that expression of LXR is increased in the livers of HBx-transgenic mice. Finally, there is a significant increase in the expression of LXRbeta (P = 0.036), SREBP-1c (P = 0.008), FAS, and stearoyl-coenyzme A desaturase-1 (P = 0.001) in hepatocellular carcinoma (HCC) in comparison with adjacent nontumorous nodules in human HBV-associated HCC specimens.

CONCLUSION

Our results suggest a novel association between HBx and LXR that may represent an important mechanism explaining HBx-induced hepatic lipogenesis during HBV-associated hepatic carcinogenesis.

Treatment outcomes and clinicopathologic characteristics of triple-negative breast cancer patients who received platinum-containing chemotherapy

The aim of this study was to evaluate the role of platinum-containing chemotherapy for metastatic triple-negative breast cancer (TNBC) patients in terms of the response rate (RR) and progression-free survival. A second aim was to characterize the clinical behavior at the time of relapse of TNBC. We retrospectively analyzed the clinical outcomes of patients with metastatic breast cancer who received taxane-platinum chemotherapy as the first- or second-line treatment, focusing on the TN phenotype. In total, 257 patients with metastatic breast cancer received platinum-containing chemotherapy at Samsung Medical Center from 1999 to 2006. Of these patients, 106 patients with available data on estrogen (ER), progesterone (PgR) and human epidermal growth factor receptor-2 (HER2) receptor status received taxane-platinum regimen as the first- or second-line treatment. The overall RR of patients with TNBC was 39%. This rate did not differ significantly from those of patients with other phenotypes. The time to death after chemotherapy (19 vs. 50 months, p = 0.037) and overall survival (OS) (21 vs. 56 months, p = 0.030) differed significantly between patients with TNBC and non-TNBC. TNBC showed a unique locoregional infiltration pattern at relapse, which might reflect its aggressive clinical behavior. Despite the similar response to platinum-containing chemotherapy, patients with TNBC had a shorter OS than patients with non-TNBC. The implication of TN phenotype as poor prognostic factor is uncertain, because it needs to be defined whether poor outcome is related to the rapid growing characteristics of tumor itself or the resistance to drug therapy. Further prospective studies are warranted.

CAMK1D amplification implicated in epithelial-mesenchymal transition in basal-like breast cancer

Breast cancer exhibits clinical and molecular heterogeneity, where expression profiling studies have identified five major molecular subtypes. The basal-like subtype, expressing basal epithelial markers and negative for estrogen receptor (ER), progesterone receptor (PR) and HER2, is associated with higher overall levels of DNA copy number alteration (CNA), specific CNAs (like gain on chromosome 10p), and poor prognosis. Discovering the molecular genetic basis of tumor subtypes may provide new opportunities for therapy. To identify the driver oncogene on 10p associated with basal-like tumors, we analyzed genomic profiles of 172 breast carcinomas. The smallest shared region of gain spanned just seven genes at 10p13, including calcium/calmodulin-dependent protein kinase ID (CAMK1D), functioning in intracellular signaling but not previously linked to cancer. By microarray, CAMK1D was overexpressed when amplified, and by immunohistochemistry exhibited elevated expression in invasive carcinomas compared to carcinoma in situ. Engineered overexpression of CAMK1D in non-tumorigenic breast epithelial cells led to increased cell proliferation, and molecular and phenotypic alterations indicative of epithelial-mesenchymal transition (EMT), including loss of cell-cell adhesions and increased cell migration and invasion. Our findings identify CAMK1D as a novel amplified oncogene linked to EMT in breast cancer, and as a potential therapeutic target with particular relevance to clinically unfavorable basal-like tumors.

Autocrine and/or paracrine growth of aggressive ATLL cells caused by HGF and c-Met

Adult T-cell leukemia/lymphoma (ATLL) is a neoplasia characterized by the massive invasion of various organs by tumor cells. Previously, we found that expression of the gene for c-Met, a receptor tyrosine kinase for hepatocyte growth factor (HGF), was specific to the acute type among 41 patients with ATLL by microarray. First in the present study, we analyzed the survival of the patients in relation to expression of c-Met and HGF in ATLL cells. Expression of the former but not the latter was associated with poor prognosis. Then, we analyzed the growth of ATLL cells caused by HGF and c-Met. c-Met was expressed in 0/7 chronic ATLLs, 12/14 acute ATLLs, 1/1 IL-2-independent ATLL cell line and 1/7 IL-2-dependent ATLL cell lines as assessed by flow cytometry. HGF induced the proliferation of primary cells from most acute cases examined as well as the c-Met-positive KK1 cell line in contrast to c-Met-negative cells. HGF induced autophosphorylation of c-Met in c-Met-positive cells from an acute case and KK1 cells. The plasma level of HGF was elevated in acute as compared to chronic cases. The levels of HGF and/or IL-6 which induces the production of HGF by stromal cells, were elevated in the supernatant of short-term cultured cells from certain patients with acute or chronic disease. Finally, infiltrated ATLL cells and adjacent stromal cells in liver were shown to be positive for c-Met/HGF and HGF, respectively, in acute cases. Autocrine and/or paracrine growth caused by HGF and c-Met was suggested in aggressive ATLL cells secreting HGF and/or IL-6, respectively.

High-resolution analysis of chromosome copy number alterations in angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma, unspecified, with single nucleotide polymorphism-typing microarrays

Angioimmunoblastic T-cell lymphoma (AILT) and peripheral T-cell lymphoma, unspecified (PTCL-u) are relatively frequent subtypes of T- or natural killer cell lymphoma. To characterize the structural anomalies of chromosomes associated with these disorders, we here determined chromosome copy number alterations (CNAs) and loss of heterozygosity (LOH) at >55,000 single nucleotide polymorphism loci for clinical specimens of AILT (n=40) or PTCL-u (n=33). Recurrent copy number gain common to both conditions was detected on chromosomes 8, 9 and 19, whereas common LOH was most frequent for a region of chromosome 2. AILT- or PTCL-u-specific CNAs or LOH were also identified at 21 regions, some spanning only a few hundred base pairs. We also identified prognosis-related CNAs or LOH by several approaches, including Cox's proportional hazard analysis. Among the genes that mapped to such loci, a poor prognosis was linked to overexpression of CARMA1 at 7p22 and of MYCBP2 at 13q22, with both genes being localized within regions of frequent copy number gain. For a frequent LOH region at 2q34, we also identified IKAROS family zinc-finger 2 cDNAs encoding truncated proteins. Our data indicate that AILT and PTCL-u consist of heterogeneous subgroups with distinct transforming genetic alterations.

Evaluation of ER and Ki-67 proliferation index as prognostic factors for survival following neoadjuvant chemotherapy with doxorubicin/docetaxel for locally advanced breast cancer

BACKGROUND

The aim of the study was to identify reliable predictive biological markers for treatment outcome following neoadjuvant adriamycin/docetaxel (AT) chemotherapy in locally advanced breast cancer patients.

MATERIALS AND METHODS

This study was a phase II study on AT neoadjuvant chemotherapy in locally advanced breast cancer patients. Patients received 50 mg/m(2) of doxorubicin intravenously (IV) over 15 min followed by docetaxel 75 mg/m(2) infused over 1 h, repeated every 3 weeks for three cycles. Surgery was performed within 3-4 weeks following the last cycle of chemotherapy. We analyzed the pre-treatment and post-treatment expression levels of ER, PgR, HER-2, Ki-67 proliferation index, and p53 and examined the correlation between the markers and clinical parameters with treatment response, overall survival and relapse-free survival following neoadjuvant treatment.

RESULTS

From July 2001 to September 2004, 61 patients were enrolled. The meaningful parameters adversely influencing survival were post-treatment ER(-) status (P = 0.013) and post-treatment Ki-67 index above 1.0% (P = 0.013). At the multivariate level, the post-treatment Ki-67 proliferation index < or = 1.0 was the only meaningful prognostic factor for better survival (P = 0.033). Notably, tumors with Ki-67 index < or = 1.0 were more likely to express ER with statistical significance (P = 0.002). Tumors with ER(+) and Ki-67 index < or = 1.0 showed the highest survival rate, followed by ER(+) and Ki-67 index > 1.0%, ER(-) and Ki-67 < or = 1.0%, and ER(-) and Ki-67 > 1.0% with the worst survival (P = 0.033).

CONCLUSION

Collectively, post-treatment ER status and Ki-67 proliferation index were prognostic of overall survival following neoadjuvant AT chemotherapy.

Relationship between p53-associated proteins and estrogen receptor status in ovarian serous neoplasms

We studied the immunoexpression of p14ARF, MDM2, and p53, in addition to relationships between those protein expressions and estrogen receptor (ER)alpha in ovarian serous tumors including benign (n= 23), borderline (n= 41), and malignant (n= 94). The aberrant expressions of p14ARF, MDM2, and p53 were observed in 19.6% (31/158), 47.5% (75/158), and 39.9% (63/158) of cases, respectively. The expression of MDM2 was significantly higher in borderline tumors compared to benign (P= 0.04) and malignant (P < 0.01) tumors. p53 expression in borderline tumors was uncommon, and p14ARF expression loss was mainly observed in carcinomas. Altered expression of p14ARF, MDM2, and p53 shows significant relationship with stage. Overexpression of MDM2 (P= 0.01) and loss of p14ARF expression (P= 0.04) were significantly associated with ER expression. Our results suggest that alteration of p14ARF-MDM2-p53 pathway proteins may contribute significantly to the tumorigenesis of ovarian serous neoplasms, and ER is involved in cellular regulation of p14ARF-MDM2-p53 pathway in ovarian serous neoplasms.

Expression of TGF-beta signaling proteins in normal placenta and gestational trophoblastic disease

The transforming growth factor beta (TGF-beta) is a vital regulator of placental development and functions. TGF-beta exerts several modulatory effects on trophoblast cells, such as inhibition of proliferation and invasiveness, and stimulation of differentiation by inducing multinucleated cell formation. In this study, we determine the expression patterns of TGF-beta signaling molecules in normal trophoblast, various hydatidiform mole types and choriocarcinoma. A total of 132 cases, including 51 normal placenta (20 first trimester, 11 second trimester, and 20 third trimester) and 81 gestational trophoblastic diseases (17 choriocarcinoma, and 64 hydatidiform moles: 39 complete, 6 partial, and 19 invasive) were immunohistochemically analyzed with anti-TGF beta1/2, TGF-beta receptor type I (TbetaRI), TbetaRII, Smad 2/3, and Smad 4 antibodies on paraffin blocks. In the case of normal placenta, maximal levels of all TGF-beta signaling molecules were observed in villous trophoblast in the first trimester, which decreased with gestational age. Expression of all the TGF-beta signaling proteins except Smad2/3, was significantly enhanced in various moles, relative to normal trophoblast. Moreover, TGF-beta signaling molecules were significantly downregulated in choriocarcinoma, compared to moles. In particular, TbetaRI and Smad2/3 levels were lower in choriocarcinoma than normal villous trophoblast (TbetaRI: p<0.025, Smad2/3: p<0.001). In conclusion, the TGF-beta signaling pathway plays an important role in the pathogenesis and progression of gestational trophoblastic disease, and may thus be employed as a potential therapeutic target and a diagnostic biomarker.

A genomic analysis of adult T-cell leukemia

Adult T-cell leukemia (ATL) is an intractable malignancy of CD4+ T cells that is etiologically associated with infection by human T-cell leukemia virus-type I. Most individuals in the chronic stage of ATL eventually undergo progression to a highly aggressive acute stage. To clarify the mechanism responsible for this stage progression, we isolated CD4+ cells from individuals in the chronic (n=19) or acute (n=22) stages of ATL and subjected them to profiling of gene expression with DNA microarrays containing >44,000 probe sets. Changes in chromosome copy number were also examined for 24 cell specimens with the use of microarrays harboring approximately 50,000 probe sets. Stage-dependent changes in gene expression profile and chromosome copy number were apparent. Furthermore, expression of the gene for MET, a receptor tyrosine kinase for hepatocyte growth factor (HGF), was shown to be specific to the acute stage of ATL, and the plasma concentration of HGF was increased in individuals in either the acute or chronic stage. HGF induced proliferation of a MET-positive ATL cell line, and this effect was blocked by antibodies to HGF. The HGF-MET signaling pathway is thus a potential therapeutic target for ATL.

Intraoperative Examination of Sentinel Lymph Nodes by Ultrarapid Immunohistochemistry in Breast Cancer

BACKGROUND

The ultrarapid immunohistochemistry (IHC) technique was applied to the intraoperative examination of sentinel lymph nodes (SLNs) because routine SLN frozen section examinations sometimes produce false-negative results. The present study was undertaken to develop a reliable protocol for the ultrarapid IHC of SLNs.

METHODS

SLNs from 79 breast cancer patients with clinically negative axillary node were examined intraoperatively by frozen hematoxylin-eosin (H&E) stain and by ultrarapid cytokeratin IHC assay. On the basis of the result of serially sectioned permanent study, the sensitivity and accuracy of each intraoperative technique were compared.

RESULTS

The total number of dissected SLNs was 178 with a mean of 2.3 (1-5) per patient. The mean turnaround time for ultrarapid IHC was 20 min. The sensitivity rates of frozen H&E staining and ultrarapid IHC were 70.0 and 85.0%, respectively (P = 0.083). Each method had a specificity of 100%. The accuracy rates for frozen H&E staining and rapid IHC were 92.4 and 96.2%, respectively (P = 0.083). Ultrarapid IHC detected one additional patient with sentinel node micrometastasis and two additional patients with isolated tumor cells (ITCs). In those patients, two underwent completion axillary dissection simultaneously and could avoid a second operation.

CONCLUSIONS

Ultrarapid cytokeratin IHC enhanced the intraoperative detection of sentinel node micrometastasis and ITCs in breast cancer without consuming much time. In patients who need completion axillary dissection after sentinel node biopsy, this technique could be helpful in avoiding a second operation.

Cloning, purification, and characterization of chitosanase from Bacillus sp. DAU101

A chitosanase-producing Bacillus sp. DAU101 was isolated from Korean traditional food. This strain was identified on the basis of phylogenetic analysis of the 16S rDNA sequence, gyrA gene, and phenotypic analysis. The gene encoding chitosanase (csn) was cloned and sequenced. The csn gene consisted of an open reading frame of 837 nucleotides and encodes 279 amino acids with a deduced molecular weight of 31,420 Da. The deduced amino acid sequence of the chitosanase from Bacillus sp. DAU101 exhibits 88 and 30 % similarity to those from Bacillus subtilis and Pseudomonas sp., respectively. The chitosanase was purified by glutathione S-transferase fusion purification system. The molecular weight of purified enzyme was about 27 kDa, which suggests the deletion of a signal peptide by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pH and temperature optima of the enzyme were 7.5 and 50 degrees C, respectively. The enzyme activity was increased by about 1.6-fold by the addition of 5 or 10 mM Ca(2+). However, Hg(2+) and Ni(+) ions strongly inhibited the enzyme. The enzyme produced, GlcN(2-4), were the major products from a soluble chitosan.

Epigenetic silencing of AXIN2 in colorectal carcinoma with microsatellite instability

Mutation or epigenetic silencing of mismatch repair genes, such as MLH1 and MSH2, results in microsatellite instability (MSI) in the genome of a subset of colorectal carcinomas (CRCs). However, little is yet known of genes that directly contribute to tumor formation in such cancers. To characterize MSI-dependent changes in gene expression, we have now compared transcriptomes between fresh CRC specimens positive or negative for MSI (n=10 for each) with the use of high-density oligonucleotide microarrays harboring >44,000 probe sets. Correspondence analysis of the expression patterns of isolated MSI-associated genes revealed that the transcriptome of MSI+ CRCs is clearly distinct from that of MSI- CRCs. Such MSI-associated genes included that for AXIN2, an important component of the WNT signaling pathway. AXIN2 was silenced, apparently as a result of extensive methylation of its promoter region, specifically in MSI+ CRC specimens. Forced expression of AXIN2, either by treatment with 5'-azacytidine or by transfection with AXIN2 cDNA, resulted in rapid cell death in an MSI+ CRC cell line. These data indicate that epigenetic silencing of AXIN2 is specifically associated with carcinogenesis in MSI+ CRCs.

Malignant lymphoma of the central nervous system: difficult histologic diagnosis after glucocorticoid therapy prior to biopsy

Four cases of central nervous system (CNS) lymphoma are reported which presented obstacles in diagnosis due to steroid treatment prior to biopsy. Reliable diagnoses were provided by molecular analysis. Malignant lymphoma of the CNS may be indistinguishable from other conditions, even in view of the gravity of the diagnosis. All patients had a previous history of glucocorticoid injection, for 2-18 days prior to stereotactic brain biopsy. The pathologic examination revealed in all cases axonal destruction and reactive gliosis with a variable infiltration of B- or T lymphocytes and macrophages. Characteristically, scattered degenerating small round cells with pyknotic or fragmented nuclei were also observed. However, the molecular assessment of paraffin-embedded tissues revealed the monoclonal IgH gene rearrangement, which allowed the confident diagnosis of B cell lymphoma. The histopathological findings of the present cases suggest that the tumor cells might be selectively destroyed by steroid treatment, which may render diagnosis impossible. Thus, molecular genetic investigation constitutes an important tool for establishing a diagnosis of CNS lymphoma obscured by steroid administration. This is especially true in cases where a paucity of tumor cells is observed or when monoclonality fails to be demonstrated by immunohistochemical tests.

An immunohistochemical study of the expression of cell-cycle-regulated proteins p53, cyclin D1, RB, p27, Ki67 and MSH2 in gallbladder carcinoma and its precursor lesions

Gallbladder carcinomas are rare but highly lethal neoplasms. We examined the expression of five cell-cycle-related molecules (p53, RB, cyclin D1, p27, Ki-67), and MSH2, in 46 carcinomas, 14 adenomas, 15 low-grade dysplasias, 9 intestinal metaplasias and 20 normal gallbladder epithelia. The expression of these molecules was altered in gallbladder carcinomas and adenomas. In gallbladder carcinomas we observed increased expression of p53, cyclin D1, Ki-67, and MSH2 together with decreased expression of RB and p27 protein. Aberrant expression of cyclin D1 and reduced expression of RB were noted in adenomas, and expression of cyclin D1 was elevated in low-grade dysplasias. However, there was no change in the levels of these cell-cycle molecules in metaplasia. Expression of p53, p27, Ki-67, and MSH2 was correlated with clinical stage (P<0.05) and there was also a correlation between the expression of Ki-67 and MSH-2 and patient age (P<0.05). These results suggest that altered expression of cell-cycle molecules p53, cyclin D1, RB, p27, and of MSH-2 is involved in the progression of gallbladder carcinomas.

Overexpression of cyclooxygenase-2 in childhood ependymomas: role of COX-2 inhibitor in growth and multi-drug resistance in vitro

The management of ependymomas remains one of the most frustrating issues in pediatric neuro-oncology. Gross total resection is not always possible, and intensive chemotherapy and craniospinal radiotherapy have made no clear advances. Moreover, the chemoresistance of ependymomas may be explained by the expression of membrane transport molecule P-glycoprotein (P-gp). In this study the expression of cyclooxygenase 2 (COX-2) and the role of the specific COX-2 inhibitor NS-398 in growth and multi-drug resistance of ependymomas were investigated. COX-2 protein expression was assessed in 19 ependymomas immunohistochemically, and the effect of NS-398 on growth and multi-drug resistance was investigated using two primary cultured ependymoma cell lines. COX-2 protein expression was observed in 15 (79%) of the 19 ependymomas. NS-398 was found to reduce the proliferation of monolayer cell cultures in a dose- and time-dependent manner and to induce apoptosis and lower bcl-2 protein levels. After NS-398 treatment, Western blotting showed reduced P-gp expression and a rhodamine 123 efflux assay demonstrated a significant decrease in P-gp activity. Our findings demonstrate that COX-2 is overexpressed in ependymomas and that NS-398 is able to induce apoptosis and suppress P-gp expression and activity.