Murat Kocer

Biological Subtypes and Survival Outcomes in Breast Cancer Patients with Brain Metastases (Study of the Anatolian Society of Medical Oncology)

Background: The aim of this study is to determine the relationship between the survival outcomes and biological subtype in breast cancer patients with brain metastases. Methods: We retrospectively evaluated clinical data from 422 breast cancer patients with brain metastases between 2001 and 2011 from referral centers in Turkey. The study population was divided into four biological subtypes according to their hormone receptor status and HER2 expression. Results: Systemic treatment prolonged median overall survival (OS) after brain metastases in the entire group (14 vs. 3.2 months, p < 0.001). It also prolonged median OS after brain metastases in the triple negative (7.5 vs. 1.6 months, p = 0.010) and luminal A (14.3 vs. 7.1 months, p = 0.003) subgroups. The median OS for untreated patients, chemotherapy and/or hormonal therapy receiving patients, and chemotherapy and/or hormonal therapy plus targeted therapy receivers was 2, 5.8, and 17.7 months, respectively (p < 0.001), in the HER2-overexpressing subgroup. In the luminal B subgroup, it was 3.7, 5.3, and 15.4 months, respectively (p = 0.003). Conclusions: The use of systemic therapy improves OS after brain metastases in all biological subgroups. Targeted therapies also improve OS after brain metastases in HER2-positive patients. The combined use of targeted therapies and lapatinib are superior to single use and trastuzumab, respectively, in these patients.

The clinicopathological and prognostic significance of CD24, CD44, CD133, ALDH1 expressions in invasive ductal carcinoma of the breast: CD44/CD24 expression in breast cancer.

BACKGROUND Recently, there are several studies about cancer stem cells (CSC), indicating that they are the cells that initiate the tumor, provide progression, metastasis and responsible for the aggressive tumor behavior. MATERIALS AND METHODS The purpose of this study is to investigate the expressions of CD24, CD44, their different combinations, ALDH1 and CD133 in invasive ductal carcinoma. Their relationships with clinicopathologic parameters, such as tumor grade, lymphovascular invasion, tumor size, axillary lymph node involvement, stage, hormone receptors, HER2 expression, basal like tumors, triple negative status and prognosis were also investigated. Tissue microarray method was used to investigate ımmunohistochemical CD24, CD44, ALDH1 and CD133 expressions in 105 invasive ductal carcinoma cases. RESULTS CD133 expression was significantly associated with tumor size (p=0.023) and stage (p=0.009). CD133 expression was decreased in tumors with larger tumor size, higher stage and lymphovascular invasion. CD133 expression was positively correlated with CD44 (r=0.212, p=0.032) and CD44(+)/CD24(+) (r=0.202, p=0.040) expressions. CD44, CD24 and ALDH1 expressions showed no significant relationship and correlation with clinicopathologic features. There was a significant relationship (p=0.048) between CD44(+)/CD24(-/low) phenotype and basal like tumors. EGFR expression was positively correlated with CD44(+)/CD24(-/low) phenotype (r=0.211, p=0.036). CONCLUSIONS Basal like tumors are enriched for CSCs with CD44(+)/CD24(-/low) phenotype. CD133 can detect a different population of CSC in breast carcinoma.

Clinicopathological Features of Patients with Malignant Mesothelioma in a Multicenter, Case-Control Study: No Role for ABO-Rh Blood Groups

BACKGROUND Malignant mesothelioma (MM) is an aggressive tumor of mesothelial surfaces. Previous studies have observed an association between ABO blood groups and risk of certain malignancies, including pancreatic and gastric cancer; however, no information on any association with MM risk is available. The aim of this study was to investigate possible associations amoong MM clinicopathological features and ABO blood groups and Rh factor. MATERIALS AND METHODS In 252 patients with MM, the ABO blood group and Rh factor were examined and compared with the control group of 3,022,883 healthy volunteer blood donors of Turkish Red Crescent between 2004 and 2011. The relationship of blood groups with various clinicopathological features were also evaluated in the patient group. RESULTS The median age was 55 (range: 27-86) and 61.5% of patients were male. While 82.8% of patients had a history of exposure to asbestos, 60.7% of patients had a smoking history. Epithelioid (65.1%) was the most common histology and 18.7% of patients had mixed histology. Overall, the ABO blood group distribution of the 252 patients with MM was comparable with the general population. The median overall survival (OS) was 14 months (95% confidence interval, 11.3-16.6 months). The median OS for A, B, AB, and O were 11, 15, 16, and 15 months respectively (p=0.396). First line chemotherapy was administered to 118 patients. The median OS of patients on pemetrexed or gemcitabine was longer than patient who was not administered chemotherapy [17 months (95%CI, 11.7-22.2) vs. 9 months (95%CI, 6.9-11.0); p<0.001]. CONCLUSIONS The results of this study suggest that patients with MM can benefit from treatment with pemetrexed or gemcitabine in combination with cisplatin. We did not observe a statistically significant association between ABO blood group and risk of MM.

Effects of bisphosphonate on oxidative stress levels in patients with different types of cancer.

We investigated the effects of bisphosphonate (BP) on oxidative stress levels in blood of patients with cancer. In total, 19 patients with cancer and 21 healthy subjects were included in the study. BP was intravenously administrated to the participants for 6 weeks. The patients had higher lipid peroxidation (LP) levels in the plasma and erythrocyte samples but lower glutathione peroxidase (GSH-Px) and plasma vitamin E values. In patients treated with BP, calcium and LP levels decreased, but GSH-Px and vitamin E values improved. In conclusion, we observed that treatment with BP alleviated oxidative stress induced by cancer.

Acute transient encephalopathy after weekly paclitaxel infusion

Paclitaxel is highly active against a variety of solid tumors including breast lung, ovarian and head and neck cancer. Although peripheral neurotoxicity is well-known side effect, central nervous system (CNS) toxicity-related standard dose of paclitaxel is extremely uncommon, because paclitaxel dose not cross the blood–brain barrier and is not detectable in the cerebrospinal fluid. We present a patient with advanced stage breast carcinoma who developed acute and spontaneous resolving encephalopathy after weekly dose of paclitaxel. The patient did not have brain metastasis, or prior whole-brain irradiation, or any type of neurosurgery. Radiological imaging studies showed no abnormalities. CNS toxicity of paclitaxel should be kept in mind in patients without a previous history of brain metastasis or brain irradiation and even with low weekly doses.

Multicenter epidemiologic study on hepatocellular carcinoma in Turkey.

BACKGROUND Hepatocellular cancer (HCC) is one of the important health problems in Turkey, being very common and highly lethal. The aim of this study was to determine clinical, demographic features and risk factors. MATERIALS AND METHODS Nine hundred and sixth-three patients with HCC from 13 cities in Turkey were included in this study. RESULTS Only 205 (21%) of the 963 patients were women, with a male:female predominance of 4.8:1 and a median age of 61 years. The etiologic risk factors for HCC were hepatitis B in 555 patients (57.6%), 453 (81%) in men, and 102 (19%) in women, again with male predominance, hepatitis C in 159 (16.5%), (14.9% and 22.4%, with a higher incidence in women), and chronic alcohol abuse (more than ten years) in 137 (14.2%) (16.8% and 4.9%, higher in males). The Child-Pugh score paralleled with advanced disease stage amd also a high level of AFP. CONCLUSIONS According to our findings the viral etiology (hepatitis B and hepatitis C infections) in the Turkish population was the most important factor in HCC development, with alcohol abuse as the third risk factor. The Child-Pugh classification and AFP levels were determined to be important prognostic factors in HCC patients.

Do high-risk features support the use of adjuvant chemotherapy in stage II colon cancer? A Turkish Oncology Group study.

BACKGROUND A high-risk group of patients with stage II colon cancer has been identified by the results of studies in Western populations. The aim of this study was to investigate the prognostic factors of adjuvant chemotherapy in Turkish patients with stage II colon cancer. METHODS A total of 554 stage II colon cancer patients were retrospectively enrolled in the study. Three hundred fifty-three patients had received adjuvant chemotherapy (5-FU-LV, FOLFOX or FLOX) and 201 had received no adjuvant chemotherapy. T4 tumor stage, lymphovascular invasion, perineural invasion, bowel obstruction and/or perforation, <12 harvested lymph nodes, and poor differentiation were defined as high-risk factors. RESULTS The median age of the patients was 62 years (range 26-88). The median disease-free survival (DFS) was 58.1 months (95% CI, 47.6 months to 68.5 months) in the non-treatment group and has not been reached in the treatment group (P <0.01). In univariate analysis, patient age >60 years and T4 tumor stage were statistically significant factors that affected DFS as poor prognostic factors. Adjuvant chemotherapy reduced the risk of recurrence with statistical significance (P <0.01). In multivariate analysis, patient age >60 years and T4 tumor stage were independent risk factors affecting DFS. In addition, adjuvant chemotherapy was an independent favorable prognostic factor for DFS (P <0.01). CONCLUSIONS Clinical and pathological risk factors in patients with stage II colon cancer may be different in the Turkish population compared to other populations. Further prospective studies in colon cancer are needed to understand the differences in biology and risk factors between races.

Immunohistochemical expression of caspase-3, caspase-5, caspase-7 and apoptotic protease-activating factor-1 (APAF-1) in the liver and kidney of rats exposed to zoledronic acid (ZOL) and basic fibroblast growth factor (bFGF)

Background: Bisphosphonates (BPs) like zoledronic acid (ZOL) are widely used for the treatment of different diseases such as osteoporosis, metastatic bone diseases and hypercalcaemia. However, the effects of BPs on apoptosis of the liver and kidney after treatment are unclear. Furthermore, basic fibroblast growth factor (bFGF) is an angiogenic molecule, which plays an important role in angiogenesis and tissue repair. The present study investigated the expression of caspase-3, -5, -7 and apoptotic protease-activating factor-1 (APAF-1) in the liver and kidney of rats treated with ZOL and bFGF. Objective: The present study investigated the expression of caspase-3, -5, -7 and apoptotic protease-activating factor-1 (APAF-1) in the liver and kidney of rats treated with ZOL and bFGF. Animals and methods: An animal model with 32 male Sprague Dawley rats was used. The effects of ZOL and bFGF on liver and kidney with the expressions of different apoptosis markers were studied histopathologically and immunohistochemically. Data were analyzed using Cronbachs alpha, Kruskal–Wallis and Bonnferroni–Dunn tests. Results: The main microscopic findings were mononuclear cell infiltrations around the bile ducts, binuclear and markedly enlarged hepatocytes (cytomegaly) and mitotic figures in the liver of rats treated with ZOL only. Immunohistochemically, both APAF-1 and caspase-3, -5 and -7 expressions were found elevated significantly (P < 0.05) in the liver and kidney of these rats. Conclusions: Our findings showed that ZOL treatment increased while bFGF treatment decreased apoptosis significantly in the liver and kidney of Sprague Dawley rats. Clinical importance: The addition of bFGF to ZOL treatment of various diseases might reduce the ZOL effects.

Effectiveness and Safety of LMWH Treatment in Patients With Cancer Diagnosed With Non-High-Risk Venous Thromboembolism: Turkish Observational Study (TREBECA):

We compared the efficacy and safety of low-molecular-weight heparins (LMWHs) in patients with cancer who are at low risk of venous thromboembolism (VTE). Patients were treated by medical oncologists in Turkey at 15 sites, where they were enrolled and followed up for a period of 12 months. Due to the study design, there was no specific treatment protocol for LMWH. Primary end points were efficacy and the time to change in VTE status. Of the included 250 patients, 239 (95.6%), 176 (70.4%), 130 (52.0%), and 91 (36.4%) completed their day 15, month 3, month 6, and month 12 visits, respectively. Number of patients treated with enoxaparin, bemiparin, and tinzaparin were 133, 112, and 5, respectively. Anticoagulant therapy provoked thrombus resolution in 1.2% and 12.7% of patients using enoxaparin and bemiparin, respectively (P = .004). Thrombus resolution was observed in 81 more patients at month 3 visit. This ratio was 35 (40.2%) of 87 and 46 (54.1%) of 85 patients administered enoxaparin and bemiparin at the third visit, respectively (P = .038). Thrombus resolution was observed in 21 more patients during month 6 visit. This ratio was 5 (7.7%) of 65 and 15 (23.4%) of 64 patients administered enoxaparin and bemiparin at the fourth visit, respectively (P = .022). The LMWH was discontinued in only 2 patients due to gastrointestinal bleeding. This pioneering study shows bemiparin is more effective than enoxaparin in thrombosis resolution and has a similar tolerability profile.

Factors predicting lapatinib efficacy in HER-2+ metastatic breast carcinoma: Does it work better in different histologic subtypes?

CONTEXT Introduction of trastuzumab, a recombinant monoclonal antibody against the extracellular domain of HER-2, is a cornerstone in the treatment of HER-2+ breast carcinoma. However, many cancers that have an initial response to trastuzumab will progress some time later. After progression on trastuzumab-based first-line treatment, there are several options. Although TDM-1 (Trastuzumab emtansine) has prolonged progression-free survival (PFS) and overall survival in patients previously treated with trastuzumab and taxane, it is still not available in Turkey. Patients may be switched to lapatinib (an oral tyrosine kinase inhibitor targeting both HER-1 and HER-2), or they may re-challenge with trastuzumab. There is no clear definition of the patients who should be switched to lapatinib. AIM In this study, we investigated the factors predicting the efficacy of lapatinib. SUBJECTS AND METHODS Totally, 94 patients treated with lapatinib for metastatic breast carcinoma was included in our study. Retrospective data including pathology, treatments and treatment results, metastatic sites, and laboratory tests were collected. RESULTS Progression-free survival was 9.1 months. Histologic subtypes other than invasive ductal carcinoma and liver metastasis were inversely related with PFS. Overall survival was 22.1 months, and patients with histologic subtypes other than invasive ductal carcinoma and who progress with brain metastasis had a worse prognosis. CONCLUSION Clinicians should give attention to histologic subtype and metastatic sites when choosing patients for lapatinib treatment.