Hae Su Kim

Association Between PD-L1 and HPV Status and the Prognostic Value of PD-L1 in Oropharyngeal Squamous Cell Carcinoma

Purpose Oropharyngeal squamous cell carcinoma (OSCC) has been recognized as an immunosuppressive disease. Various mechanisms have been proposed for immune escape, including dysregulation of immune checkpoints such as the PD-1:PD-L1 pathway. We investigated the expression of programmed cell death-ligand 1 (PD-L1) in HPV-negative and HPV-positive OSCC to determine its prevalence and prognostic relevance. Materials and Methods Using immunohistochemistry, 133 cases of OSCC were evaluated for expression of PD-L1. Formalin-fixed paraffin-embedded tumor samples were stained with monoclonal antibody (clone 5H1) to PD-L1. PD-L1 positivity was defined as membrane staining in ≥20% of tumor cells. Correlations between PD-L1 expression and HPV status and survival parameters were analyzed. Results Of the 133 patients, 68% showed PD-L1 expression, and 67% of patients were positive for p16 expression by immunohistochemistry. No significant difference in PD-L1 expression was observed between HPV(-) and HPV(+) tumors (61% vs. 71%, p=0.274). No significant difference in age, gender, smoking history, location of tumor origin, or stage was observed according to PD-L1 status. With a median follow-up period of 44 months, older age (≥65) (p=0.017) and T3-4 stage (p<0.001) were associated with poor overall survival (OS), whereas PD-L1 expression did not affect OS in univariate and multivariate analysis. Conclusion PD-L1 expression was observed in the majority of OSCC patients regardless of HPV status. Further large prospective studies are required to determine the role of PD-L1 expression as a prognostic or predictive biomarker, and clinical studies of immune checkpoint inhibitors in OCSS are warranted regardless of HPV status.

Mutational profiling of brain metastasis from breast cancer: matched pair analysis of targeted sequencing between brain metastasis and primary breast cancer

Although breast cancer is the second most common cause of brain metastasis with a notable increase of incidence, genes that mediate breast cancer brain metastasis (BCBM) are not fully understood. To study the molecular nature of brain metastasis, we performed gene expression profiling of brain metastasis and matched primary breast cancer (BC). We used the Ion AmpliSeq Cancer Panel v2 covering 2,855 mutations from 50 cancer genes to analyze 18 primary BC and 42 BCBM including 15 matched pairs. The most common BCBM subtypes were triple-negative (42.9%) and basal-like (36.6%). In a total of 42 BCBM samples, 32 (76.2%) harbored at least one mutation (median 1, range 0–7 mutations). Frequently detected somatic mutations included TP53 (59.5%), MLH1 (14.3%), PIK3CA (14.3%), and KIT (7.1%). We compared BCBM with patient-matched primary BC specimens. There were no significant differences in mutation profiles between the two groups. Notably, gene expression in BCBM such as TP53, PIK3CA, KIT, MLH1, and RB1 also seemed to be present in primary breast cancers. The TP53 mutation frequency was higher in BCBM than in primary BC (59.5% vs 38.9%, respectively). In conclusion, we found actionable gene alterations in BCBM that were maintained in primary BC. Further studies with functional testing and a delineation of the role of these genes in specific steps of the metastatic process should lead to a better understanding of the biology of metastasis and its susceptibility to treatment.

A Phase Ib/II Study of Afatinib in Combination with Nimotuzumab in Non-Small Cell Lung Cancer Patients with Acquired Resistance to Gefitinib or Erlotinib

Purpose: In this phase Ib/II study, we aimed to assess the safety and efficacy of afatinib plus nimotuzumab (N) in advanced non–small cell lung cancer (NSCLC) patients with acquired resistance to gefitinib or erlotinib. Experimental Design: In phase Ib stage, patients received afatinib (40 mg or 30 mg once daily) plus nimotuzumab (100 mg or 200 mg once weekly) for 28-day cycles to determine the recommended phase II dose (RPIID). The safety and efficacy of RPIID dose was evaluated in phase II stage. Results: In total, 50 patients were enrolled (13 to phase Ib and 37 to phase II). In the first dose-finding cohort (afatinib 40 mg plus nimotuzumab 100 mg), one patient experienced dose-limiting toxicity (DLT) of grade 3 diarrhea and in the subsequent cohort (afatinib 40 mg plus nimotuzumab 200 mg), two DLTs (grade 3 diarrhea and grade 3 neutropenia) occurred in 2 of 6 patients. Accordingly, RPIID was determined as afatinib 40 mg plus nimotuzumab 100 mg. In 44 patients treated with RPIID, 7 (16%) patients had grade 3 toxicities; skin rash (7%), diarrhea (5%), acne (2%), and fatigue (2%). The overall response rate was 23% and the median duration of response was 4.3 months (range, 0.7–16.2 months). The median progression-free survival and overall survival were 4.0 months [95% confidence interval (CI), 2.3–5.7 months] and 11.7 months (95% CI, 9.4–14.0 months), respectively. Conclusions: Combination treatment of afatinib and nimotuzumab demonstrated an acceptable safety profile and encouraging antitumor activity in advanced NSCLC patients with acquired resistance to gefitinib or erlotinib. Larger phase III trial is warranted to confirm its efficacy and safety. Clin Cancer Res; 22(9); 2139–45. ©2015 AACR.

MCT4 as a potential therapeutic target for metastatic gastric cancer with peritoneal carcinomatosis

Monocarboxylate transporters (MCTs) play a major role in up-regulation of glycolysis and adaptation to acidosis. However, the role of MCTs in gastric cancer (GC) is not fully understood. We investigated the potential utilization of a new cancer therapy for GC. We characterized the expression patterns of the MCT isoforms 1, 2, and 4 and investigated the role of MCT in GC through in vitro and in vivo tests using siRNA targeting MCTs. In GC cell lines, MCT1, 2, and 4 were up-regulated with different expression levels; MCT1 and MCT4 were more widely expressed in GC cell lines compared with MCT2. Inhibition of MCTs by siRNA or AR-C155858 reduced cell viability and lactate uptake in GC cell lines. The effect of inhibition of MCTs on tumor growth was also confirmed in xenograft models. Furthermore, MCT inhibition in GC cells increased the sensitivity of cells to radiotherapy or chemotherapy. Compared with normal gastric tissue, no significant alterations of expression levels in tumors were identified for MCT1 and MCT2, whereas a significant increase in MCT4 expression was observed. Most importantly, MCT4 was highly overexpressed in malignant cells of acsites and its silencing resulted in reduced tumor cell proliferation and lactate uptake in malignant ascites. Our study suggests that MCT4 is a clinically relevant target in GC with peritoneal carcinomatosis.

A Prospective Phase II Study of Cisplatin and Cremophor EL-Free Paclitaxel (Genexol-PM) in Patients with Unresectable Thymic Epithelial Tumors

Background: We conducted a prospective phase II study of cisplatin plus cremophor EL-free paclitaxel (Genexol-PM) in patients with unresectable thymic epithelial tumors to determine the efficacy and tolerability of the combination therapy. Methods: Patients were treated with cisplatin (70 mg/m2) and Genexol-PM (230 mg/m2) on day 1 of a 3-week cycle as first-line palliative chemotherapy. The primary end point of this study was objective response rate, and the secondary end points included toxicity, progression-free survival (PFS), overall survival, correlation between early 18F-fluorodeoxyglucose positron emission tomography/computed tomography response and PFS, and correlation between baseline flurododeoxyglucose uptake and histology. Results: Forty-two patients with unresectable thymoma (n = 14) or thymic carcinoma (n = 28) were enrolled between May 2012 and October 2014. The median age was 59 years (range: 25–77) and 30 patients (71%) were male, and 39 patients (93%) had an ECOG PS of 1. The median number of treatment cycles was six (range: 1–6). For 40 assessable patients, the objective response rate was 62.5% (95% confidence interval [CI]: 47.6–77.4) with rates of 46% (95% CI: 23.3–76.9) for advanced thymoma (n = 13) and 70% (95% CI: 52.0–82.1) for thymic carcinoma (n = 27). With a median follow-up of 15.5 months, the median PFS for all 42 patients was 9.8 months (11.4 months for thymoma versus 8.1 months for thymic carcinoma). The 2-year overall survival was 77.9% for thymoma and 65.9% for thymic carcinoma. There were no treatment-related deaths. The most common grade 3 and 4 treatment-related adverse event was neutropenia in 11 patients (26%). Eight patients (19%) experienced grade 2 hypersensitivity reactions. There was no correlation between early positron emission tomography response and PFS, but tumor histology (thymoma versus thymic carcinoma) was correlated with SUVmax before chemotherapy. Conclusions: These data suggest that combination of cisplatin and Genexol-PM is highly effective and tolerable for the treatment of unresectable thymic epithelial tumors.

Clinicopathologic Features and Long-Term Outcomes of Elderly Breast Cancer Patients: Experiences at a Single Institution in Korea

Purpose The purpose of this study was to assess the tumor characteristics and long-term clinical outcomes of adjuvant treatments after surgery with a curative aim for patients with breast cancer who are 65 years and older. Materials and Methods Patients with breast cancer who underwent curative surgery from 2000 to 2009 were analyzed (n=4,388). Tumor characteristics and survival outcome were compared by dividing the patients into two age groups (< 65 and ≥ 65 years old). The Kaplan-Meier method was used for comparison of survival rates by log-rank test, and a Cox regression model was used to examine the effect of variables. Results Among 4,388 patients with invasive breast cancer, 317 patients (7.2%) were 65 years or older and the median age of all patients was 47 years (range, 18 to 91 years). Tumor characteristics were similar between the two age groups, but the older patients were treated less often with adjuvant treatments. During a median follow-up period of 122 months, recurrence-free survival (RFS) was equivalent for patients 65 years and older compared to younger patients, but significantly worse in overall survival (OS) and breast cancer–specific survival (BCSS) (5-year OS, 94.3% vs. 90.5%; p < 0.001 and 5-year BCSS, 94.7% vs. 91.8%; p=0.031). In the multivariate model, age ≥ 65 years old was identified as an independent risk factor for OS and RFS. Conclusion Elderly breast cancer appeared to have worse outcomes with very low prevalence in Korea, despite similar tumor characteristics. More active adjuvant therapies would have a role for aggressive subtypes for fit, elderly patients.

Genetic Alterations and Their Clinical Implications in High-Recurrence Risk Papillary Thyroid Cancer

Purpose Papillary thyroid carcinomas (PTCs) frequently involve genetic alterations. The objective of this study was to investigate genetic alterations and further explore the relationships between these genetic alterations and clinicopathological characteristics in a high-recurrence risk (node positive, N1) PTC group. Materials and Methods Tumor tissue blocks were obtained from 240 surgically resected patients with histologically confirmed stage III/IV (pT3/4 or N1) PTCs. We screened gene fusions using NanoString’s nCounter technology and mutational analysis was performed by direct DNA sequencing. Data describing the clinicopathological characteristics and clinical courses were retrospectively collected. Results Of the 240 PTC patients, 207 (86.3%) had at least one genetic alteration, including BRAF mutation in 190 patients (79.2%), PIK3CA mutation in 25 patients (10.4%), NTRK1/3 fusion in six patients (2.5%), and RET fusion in 24 patients (10.0%). Concomitant presence of more than two genetic alterations was seen in 36 patients (15%). PTCs harboring BRAF mutation were associated with RET wild-type expression (p=0.001). RET fusion genes have been found to occur with significantly higher frequency in N1b stage patients (p=0.003) or groups of patients aged 45 years or older (p=0.031); however, no significant correlation was found between other genetic alterations. There was no trend toward favorable recurrence-free survival or overall survival among patients lacking genetic alterations. Conclusion In the selected high-recurrence risk PTC group, most patients had more than one genetic alteration. However, these known alterations could not entirely account for clinicopathological features of high-recurrence risk PTC.

Clinical features and treatment outcomes of blastic plasmacytoid dendritic cell neoplasm: a single-center experience in Korea

Background/Aims Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that typically presents in the form of skin manifestations with or without lymph node and bone marrow involvement. Given its rarity and recent recognition as a distinct pathological entity, no standard of treatment exists for this aggressive disease and its prognosis is particularly dismal. Methods We retrospectively analyzed clinical features and treatment outcomes of patients who were diagnosed with BPDCN between 2000 and 2014. Results Ten patients had a median age at diagnosis of 41 years (range, 18 to 79), and seven patients were male. Sites of disease involvement were the skin (n = 7), lymph node (n = 5), bone marrow (n = 2), liver (n = 2), spleen (n = 2), and soft tissue (n = 1). Intensified chemotherapy regimens such as hyperCVAD regimen (cyclophosphamide, vincristine, doxorubicin, dexamethasone, methotrexate, cytarabine), and VPDL (vincristine, methylprednisolone, daunorubicin, L-asparaginase) were used as a first-line treatment. Although all patients treated with intensified chemotherapy showed an objective response (five patients with complete response) with median progression-free survival of 11.2 months (range 6.2 to 19.4), complete remission was not sustained for more than 2 years in any case. The response was relatively long-lived compared with previously reported CHOP (doxorubicin, cyclophosphamide, vincristine, prednisone)-like regimens, but the above regimens do not result in long-term remission. Conclusions All patients treated with hyperCVAD or VPDL showed an objective response, but the duration of response was relatively short. Thus, the development of more effective induction as well as consolidation treatment strategy should be warranted to improve this rare disease entity.

Macrophage inflammatory protein 1 alpha (MIP-1α) may be associated with poor outcome in patients with extranodal NK/T-cell lymphoma

The macrophage inflammatory protein 1α (MIP‐1α) is anticipated to have a role in extranodal natural killer (NK)/T‐cell lymphoma (ENKTL) because the expression of MIP‐1α is related to Epstein–Barr virus (EBV) latency in EBV‐related non‐Hodgkin lymphoma cells. Thus, we measured the serum level of MIP‐1α in 69 patients with ENKTL using frozen serum samples that were archived at diagnosis. As serum level of MIP‐1α was not detectable in 19 patients (range: 0–24.37 pg/mL), patients were dichotomized into positive (n = 50) and negative (n = 19) MIP‐1α groups according to the presence of detectable level of MIP‐1α in serum. MIP‐1α‐positive group showed a significantly poor overall survival (OS) in comparison with the MIP‐1α‐negative group (p = 0.004). In the subgroup analysis, the positivity of MIP‐1α was significantly associated with OS in patients with stage IIIE/IV and a detectable level of EBV DNA (p = 0.002 and 0.032, respectively). Multivariate analysis also showed that the positivity of MIP‐1α was independently associated with worse OS together with bone marrow involvement (p = 0.002). An in vitro study with patient‐derived ENKTL tumour cells showed the expression of CCR1 and CCR5 on the surface of tumour cells (28% and 14%, respectively) , and the addition of MIP‐1α to the culture media of tumour cells increased cell growth supporting the negative impact of MIP‐1α on the prognosis of ENKTL patients. In conclusion, serum levels of MIP‐1α could predict survival outcomes in patients with ENKTL. Therefore, MIP‐1α should be considered for prognostication and a potential therapeutic target. Copyright

Weekly docetaxel and gemcitabine in previously treated metastatic esophageal squamous cell carcinoma

AIM To assess the efficacy and safety of weekly docetaxel plus a fixed-dose rate (FDR) of gemcitabine in metastatic esophageal squamous cell carcinoma (SCC). METHODS A multi-center, open-label, prospective phase II study was designed. Thirty-three esophageal SCC patients with documented progression after fluoropyrimidine/platinum-based first-line chemotherapy were enrolled and treated with docetaxel 35 mg/m(2) and gemcitabine 1000 mg/m(2) iv at a FDR (10 mg/m(2) per minute) on days 1 and 8. Treatment was repeated every twenty-one days until disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was response rate (RR), and secondary endpoints were safety, progression-free survival (PFS) and overall survival (OS). RESULTS Combination of weekly docetaxel and FDR gemcitabine was well tolerated: the most common treatment-related adverse events were anemia (97%), fatigue (64%) and neutropenia (55%). One patient with multiple lung and lymph node metastases died of respiratory failure after receiving four cycles of chemotherapy, and the possibility of drug-induced pneumonitis could not be completely excluded. Disease control (objective response plus stable disease) in the ITT population was achieved in 88% of patients, and the overall RR was 30% (95%CI: 15%-46%). The median PFS and OS were 4.0 (95%CI: 3.4-4.6) and 8.8 mo (95%CI: 7.8-9.8 mo), respectively. CONCLUSION A combination of weekly docetaxel and FDR gemcitabine showed promising antitumor activity and tolerability in previously treated, metastatic esophageal SCC.