Researcher:
Ertürk, Kayhan

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Kayhan

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Ertürk

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Ertürk, Kayhan

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2020 - 202327

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    Median age of cutaneous melanoma presentation in Turkey from a single tertiary center is younger than other western countries
    (Springer) Tas, Faruk; N/A; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
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    Complementary and alternative medicine (CAM) in Turkish cutaneous melanoma patients: a prospective study from tertiary cancer center
    (Sage Publications Ltd, 2022) Tas, Faruk; Cinar, Ebru; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    Background: Only a few studies assessed the prevalence and the predictors of complementary and alternative medicine (CAM) use specifically in melanoma patients. The aim of this study was to assess the extent of CAM use in Turkish melanoma patients. Objective: To assess the extent of CAM use and to compare sociodemographic and clinical characteristics between users and non-users in melanoma patients. Methods: One hundred melanoma patients who were seen in outpatient clinics were included in a survey using questionnaire on CAM use. Results: Twenty-seven patients used at least one type of CAM, the majority of which were herbs (73%). Turmeric (curcumin) was the most popular herb that was used alone or in conjunction with various other herbs (41%). Living in rural areas was significantly associated with CAM use (p = 0.02). The most common reason for CAM use was intent to cure of the disease (52%). The primary source of information about CAM was a close friend or a family contact (44%). CAMs were generally used together with conventional anticancer treatment modalities (64%) and they were ingested on a regular base (72%). CAMs could easily be acquired at regular herbal stores (88%). The patients experienced almost no adverse effects with CAM use; and most cases (71%) had confidence in CAM. About half of the patients consulted with their physicians about CAM use. Conclusion: Minority, nearly one fourth of the melanoma cases used at least one type of CAM, the majority of which were herbs and turmeric (curcumin) was the most popular agent.
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    Serum folate and vitamin B12 levels in cutaneous melanoma
    (Wiley, 2021) Tas, Faruk; Soydinc, Hilal Oguz; N/A; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    Background: Vitamin B12 and folate are the major micronutrients that play significant roles in DNA synthesis. Epidemiological studies and clinical evidences displayed alterations in serum concentrations folate and of vitamin B12 in various human malignancies, yet their roles in patients with melanoma have yet to be understood. Objective: To assess circulating vitamin B12 and folate concentrations of patients with melanoma and compare them with other malignant tumors and healthy subjects. Methods: A total of 98 skin melanoma cases from university clinic were enrolled into the study. Serum vitamin B12 and folate concentrations were analyzed by electrochemiluminescence binding assay. Results: Circulating levels of vitamin B12 in patients with melanoma were similar compared with other malignancies and healthy controls (P > .05). However, melanoma cases had significantly lower serum folate concentrations than healthy control group (P = .04). Melanoma patients with metastatic disease (P = .001) and with short history of disease (P = .05), and those who had active diseases in course of the study (P = .04) had low serum folate concentrations. Conclusion: Serum levels of folate were found significantly lower in melanoma cases, and this association was stronger for patients with metastatic melanoma; however, no such association was found between melanoma and serum vitamin B12 levels.
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    De novo and nevus-associated melanomas: different histopathologic characteristics but similar survival rates
    (Springer, 2020) Tas, Faruk; N/A; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    The clinical significances of de novo and nevus-associated melanomas are controversial. In this study, we investigated the correlations of these forms of melanomas in respect to their pathological and clinical features and patient outcomes. The data of 660 pathologically confirmed Turkish-Caucasian melanoma patients, whose tumors were either associated with a pre-existing melanocytic nevus or not, were analyzed retrospectively. They were treated and followed up at a single tertiary referral center. A total of 440 de novo (66.7%) and 220 nevus-associated melanomas (33.3%) were enrolled into the study. The median age of the patients was 51 years. The patients consisted of 341 men (51.7%) and 319 women (48.3%). There were significant correlations between de novo melanomas and advanced age (p = 0.003), tumor thickness greater than 2 mm (p = 0.0001), ulceration (p = 0.01) and high mitotic rate (p = 0.03). On the other hand, nevus-associated melanomas were found significantly associated with histological regression (p = 0.03) and BRAFV600E mutation (p = 0.003). Most of the nevus-associated melanomas were found on trunk and head/neck, whereas extremities were more frequently inflicted by de novo melanomas (p = 0.0001). Furthermore, none of other variables, such as sex, histopathology, lymph node involvement and presence of metastasis, showed statistically significant difference between de novo and nevus-associated melanoma patients (p > 0.05). The 5-year DFS rates were 62.4% and 72.7% for de novo melanoma and for nevus-associated melanoma patients, respectively (p = 0.1). The 5-year OS rate were 72.1% and 76.4% for de novo melanoma and nevus-associated melanoma patients, respectively (p = 0.2). In conclusion, even though de novo melanomas are more significantly correlated with aggressive histopathologic variables, such as tumor depth, ulceration and high mitotic rate, the survival rates of de novo and nevus-associated melanomas are similar.
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    Single-agent temozolomide may be an effective option for late adjuvant therapy in patients with melanoma
    (Sage Publications Ltd, 2021) Tas, Faruk; N/A; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    Background Late adjuvant therapy is the term to define the treatment administered following complete resection of metastatic or relapsed disease. Objective To assess the efficacy of single-agent temozolomide, a standard agent is used for metastatic melanoma in late adjuvant chemotherapy for cutaneous melanoma. Methods Twenty-seven adult cutaneous melanoma patients whose relapses were completely resected were included in this study. Temozolomide was administered as follows: peroral, 200 mg/m(2) once daily for five consecutive days of a 28-day treatment cycle for six cycles. Results The median age was 55 years and men were predominant (74%). Median follow-up time was 23.6 months (range, 3.6-122.6 months). Any type of relapse occurred in 14 (51.9%) patients, and five patients relapsed while on chemotherapy. Almost all relapses (n = 13, 93%) occurred within the first two years of follow-up. The relapse rates were found 37.4 and 49.1% in the first and second years of follow-up, respectively. Moreover, after fifth year of onset of chemotherapy, relapse rate was found only 51.9%. The median relapse-free survival (RFS) was 12.9 months, and 1-, 2-, 3-, and 5-year RFS rates were 60, 46, 39, and 39%, respectively. The estimated median overall survival was 23.6 months. All patients survived first year (n = 27, 100%), and the overall survival rates for 2, 3, and 5 years were 81, 48, and 48%, respectively. Conclusion Single-agent temozolomide may be a rational and prudent option for late adjuvant therapy in melanoma patients if/when novel therapies, such as targeting and immune therapies, are not accessible or available.
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    Larger tumors are associated with poorer prognostic factors in cutaneous melanoma
    (Springer India, 2022) Taş, Faruk; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
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    Using Google as a source of information about breast cancer
    (Springer India, 2022) Taş, Faruk; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
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    Major histotypes in skin melanoma: nodular and acral lentiginous melanomas are poor prognostic factors for relapse and survival
    (Lippincott Williams and Wilkins (LWW), 2022) Taş, Faruk; N/A; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    The histological subtype is not considered one of the major prognostic factors in melanoma, yet it is known to have an impact on survival. The aim of this study was to investigate the clinical significance of histological subtypes and the possible impacts of clinicopathological factors on the course of melanoma patients of all stages. A total of 1017 cutaneous melanoma patients were analyzed retrospectively. Four major melanoma histotypes that were studied in this study were as follows: (1) superficial spreading melanoma (SSM), (2) nodular melanoma (NM), (3) acral lentiginous melanoma (ALM), and (4) lentigo maligna melanoma (LMM). Unlike SSMs and LMMs, there were statistically significant correlations between NMs and ALMs and most aggressive histopathological prognostic indicators, such as higher Clark level (P = 0.0001), thick Breslow depth (P = 0.0001), presence of ulceration (P = 0.0001), and lymphovascular invasion (P = 0.0001). Furthermore, NMs and ALMs were also associated with advanced clinical stages, that is, node involvement and metastasis. Relapse rates for nonmetastatic melanomas were higher in NMs (39.6%) and ALMs (35.3%) than in SSMs (24.3%) and LMMs (10.3%) (P = 0.0001). Additionally, 5-year relapse-free survival rates were 90.5%, 70.5%, 55.7%, and 50.5% in LMMs, SSMs, ALMs, and NMs, respectively (P = 0.0001). Moreover, 5-year overall survival rates plummeted from 84.3% in LMMs to 74.8%, 64.3%, and 46% in SSMs, ALMs, and NMs, respectively (P = 0.0001). In conclusion, we observed that the histologic subtype was an independent predictor for relapse and outcome for cutaneous melanoma patients. Both NM and ALM had unfavorable prognoses, and they were associated with known poor pathological and clinical indicators.
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    Nivolumab for metastatic uveal melanoma: a multicenter, retrospective study
    (Lippincott Williams and Wilkins (LWW), 2021) Tacar, Seher Yıldız; Yılmaz, Mesut; Sarıcı, Ahmet Murat; Gültürk, İlkay; Ayhan, Murat; Tural, Deniz; Selçukbiricik, Fatih; Ertürk, Kayhan; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 202015; N/A
    Systemic treatment options with proven efficacy for the treatment of metastatic uveal melanoma are limited. In this study, we aimed to evaluate the efficacy of nivolumab in metastatic uveal melanoma patients. In our multi-center study, the files of patients who received nivolumab treatment with a diagnosis of metastatic uveal melanoma were retrospectively reviewed and their information was recorded. Seventeen patients were enrolledand 16 patients were evaluable for efficacy. The objective response rate (ORR) was 18% including one confirmed complete response and two confirmed partial responses. The median progression-free survival (PFS) was 5.8 months (95% CI, 0.03-11.57 months), and the median overall survival (OS) was 10.5 months (95% CI, 3.87-14.14 months). Significant longer OS and PFS were observed in patients with the performance status of the Eastern Cooperative Oncology Group (ECOG-PS) 0. Although significant longer OS was detected in patients with low median lactate dehydrogenase (LDH) levels, no significant difference was found in PFS. Grade 1 and 2 fatigue and decreased appetite were the most common side effects associated with treatment (17%); grade 3 and 4 side effects were not observed. Immunotherapy is also emerging as a treatment option among the limited number of treatment options in metastatic uveal melanoma (mUM), but its efficacy needs to be demonstrated with prospective studies involving a larger number of patients.
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    Completion lymph node dissection is unnecessary after positive sentinel lymph node in melanoma - a case series analysis
    (Springer India, 2022) Taş, Faruk; Ferhatoğlu, Ferhat; Ertürk, Kayhan; Faculty Member; School of Medicine; Koç University Hospital; N/A
    In recent times, significant trials showed that sentinel lymph node biopsy alone was therapeutic in melanoma and no further surgery was necessary even if sentinel lymph node biopsy was found positive. In this retrospective study, we aimed to determine the prognostic importance of the total number of excised lymph nodes after sentinel lymph node biopsy in pN1 stage III melanoma patients from a single tertiary cancer centre. A total of 194 stage III primary melanoma patients with only one metastatic regional lymph node (pN1) determined by sentinel lymph node biopsy were included in the study. All patients with pathologically positive sentinel lymph node biopsy underwent a completion of lymphadenectomy. The numbers of excised lymph nodes were divided into the groups 1 to 5, 6 to 10, 11 to 15, and >= 16. The estimated 5-year relapse-free survival of all patients was 44.3% and there was no significant association between increasing excised lymph node groups and relapse-free survival (p = 0.3). Moreover, the 5-year overall survival for all cases was 48.7% and no significant association between increasing excised lymph node groups and overall survival was observed (p > 0.05). In conclusion, we suggest no prognostic impact for the extended removal of lymph nodes on relapse and outcome in pN1 melanoma patients after sentinel lymph node biopsy.