The real-world outcomes of Lutetium-177 PSMA-617 radioligand therapy in metastatic castration-resistant prostate cancer: Turkish Oncology Group multicenter study.

Metastatic castration-resistant prostate cancer (mCRPC) remains a challenging condition to treat despite recent advancements. This retrospective study aimed to assess the activity and tolerability of Lutetium-177 (Lu-177) PSMA-617 radioligand therapy (RLT) in mCRPC patients across multiple cancer centers in Turkey. The study included 165 patients who received at least one cycle of Lu-177 PSMA-617 RLT, with the majority having bone metastases and undergone prior treatments. Prostate-specific antigen (PSA) levels were assessed before each treatment cycle, and the biochemical response was evaluated in accordance with the Prostate Cancer Work Group 3 Criteria. The PSA decline of ≥50% was classified as a response, while an increase of ≥25% in PSA levels was indicative of progressive disease. Neither response nor progression was considered as stable disease. The Lu-177 PSMA-617 RLT led to a significant PSA response, with 50.6% of patients achieving a >50% decrease in PSA levels. Median overall survival (OS) and progression-free survival were 13.5 and 8.2 months, respectively. Patients receiving Lu-177 PSMA-617 RLT in combination with androgen receptor pathway inhibitors (ARPIs) had a higher OS compared to those receiving Lu-177 PSMA-617 RLT alone (18.2 vs 12.3 months, P = .265). The treatment was generally well-tolerated, with manageable side effects such as anemia and thrombocytopenia. This study provides real-world evidence supporting the effectiveness and safety of Lu-177 PSMA-617 RLT in mCRPC patients, particularly when used in combination with ARPIs. These findings contribute to the growing body of evidence on the potential benefits of PSMA-targeted therapies in advanced prostate cancer.

Comparing the efficacy of regorafenib and 5-fluorouracil-based rechallenge chemotherapy in the third-line treatment of metastatic colorectal cancer.

BACKGROUND: The optimal treatment for metastatic colorectal cancer (mCRC) after the second line is still controversial. Regorafenib has been the standard of care in this setting as it improved overall survival (OS) compared to placebo. In real-world practice chemotherapy rechallenge is also a preferred option even though supporting evidence is not enough. We aim to compare the efficacy of regorafenib and 5-fluorouracil-based (5-FU) rechallenge treatment in the third line setting of mCRC. METHODS: In this retrospective multi-institutional trial, mCRC patients from 21 oncology centers who progressed after 2 lines of chemotherapy were analyzed. Patients who were treated with regorafenib or rechallenge therapy in the third-line setting were eligible. Rechallenge chemotherapy was identified as the re-use of the 5-FU based regimen which was administered in one of the previous treatment lines. OS, disease control rate (DCR), progression free survival (PFS) and toxicity were analyzed. RESULTS: Three hundred ninety-four mCRC patients were included in the study. 128 (32.5%) were in the rechallenge, and 266 (67.5%) were in the regorafenib group. Median PFS was 5.82 months in rechallenge and 4 months in regorafenib arms (hazard ratio:1.45,95% CI, p = 0.167). DCR was higher in the rechallenge group than regorafenib (77% vs 49.5%, respectively, p = < 0.001). Median OS after the third-line treatment was 11.99 (95% CI, 9.49-14.49) and 8.08 months (95% CI, 6.88-9.29) for rechallenge and regorafenib groups, respectively (hazard ratio:1.51, 95% CI, p < 0.001). More adverse effects and discontinuation were seen with regorafenib treatment. CONCLUSION: Our study revealed that higher disease control and OS rates were achieved with rechallenge treatment compared to regorafenib, especially in patients who achieved disease control in one of the first two lines of therapy.

The efficacy of palbociclib and ribociclib in the first-line treatment of metastatic hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer in male patients: a Turkish oncology group (TOG) study.

INTRODUCTION: Male breast cancer, comprising approximately 1% of all breast cancer cases, often leads to the exclusion of male patients as a criterion in clinical trials. While the efficacy of Cyclin-dependent kinases 4 and 6 (CDK 4/6) inhibitors has been established in metastatic hormone receptor-positive (HR +) and human epidermal growth factor receptor 2-negative (HER2 -) breast cancer in women, limited data exist on their effectiveness in male patients. We aimed to evaluate the efficacy and safety of palbociclib or ribociclib in male patients with breast cancer. METHODS: This study is a multicenter, retrospective study. We included male patients with HR + and HER2-metastatic breast cancer who received palbociclib or ribociclib as first-line treatment. Our primary endpoints were progression-free survival (PFS), overall response rates (ORR), and drug-related adverse effects. RESULTS: A total of 46 male patients from 27 institutions were enrolled. The median age at initiation of CDK 4/6 inhibitors was 63.64 ± 13.69 years, with a median follow-up of 21.33 (95% CI 14.92-27.74) months. The ORR were 84% for palbociclib and 76.2% for ribociclib. The mPFS for the entire cohort was 28.06 months (95% CI 18.70-37.42). No significant difference in PFS was observed between palbociclib and ribociclib (mPFS: 24.46 months (95% CI 11.51-37.42) vs 28.33 months (95% CI 14.77-41.88), respectively, p = 0.211). No new adverse events were reported. DISCUSSION: This study demonstrates that palbociclib and ribociclib are effective and safe options for first-line treatment in male patients with HR + /HER2 - metastatic breast cancer. However, further prospective studies are warranted to establish their efficacy in this population.

Real-world evaluation of nivolumab in patients with non-nasopharyngeal recurrent or metastatic head and neck cancer: a retrospective multi-center study by the Turkish Oncology Group (TOG).

OBJECTIVES: Head and neck cancers (HNCs) represent a significant global health concern due to high morbidity and mortality rates. Despite therapeutic advances, the prognosis for advanced or recurrent cases remains challenging. Nivolumab obtained approval for recurrent or metastatic HNC based on the Phase III CheckMate 141 trial. This study aimed to evaluate the real-world outcomes of nivolumab in patients with non-nasopharyngeal HNC. DESIGN: In this multicenter retrospective study, we analyzed 124 patients with recurrent or metastatic non-nasopharyngeal HNC who received nivolumab in the second-line setting and beyond. Data were collected from 20 different cancer centers across Turkey. The effectiveness and safety of the treatment and survival outcomes were evaluated. RESULTS: Nivolumab exhibited favorable clinical responses, yielding an objective response rate of 29.9% and a disease control rate of 55.7%. Safety assessments revealed a generally well-tolerated profile, with no instances of treatment discontinuation or mortality due to side effects. Survival analysis disclosed a median overall survival (OS) of 11.8 (95% CI 8.4-15.2) months. Multivariate analysis revealed that ECOG-PS ≥ 1 (HR: 1.64, p = 0.045), laryngeal location (HR: 0.531, p = 0.024), and neutrophil-to-lymphocyte ratio > 3.5 (HR: 1.97, p = 0.007) were independent predictors of OS. CONCLUSIONS: Nivolumab is an effective and safe treatment option for patients with recurrent or metastatic non-nasopharyngeal HNC in real-world settings. Further studies are needed on factors affecting response to treatment and survival outcomes.

Efficacy of subsequent treatments in patients with hormone-positive advanced breast cancer who had disease progression under CDK 4/6 inhibitor therapy.

BACKGROUND: There is no standard treatment recommended at category 1 level in international guidelines for subsequent therapy after cyclin-dependent kinase 4/6 inhibitor (CDK4/6) based therapy. We aimed to evaluate which subsequent treatment oncologists prefer in patients with disease progression under CDKi. In addition, we aimed to show the effectiveness of systemic treatments after CDKi and whether there is a survival difference between hormonal treatments (monotherapy vs. mTOR-based). METHODS: A total of 609 patients from 53 centers were included in the study. Progression-free-survivals (PFS) of subsequent treatments (chemotherapy (CT, n:434) or endocrine therapy (ET, n:175)) after CDKi were calculated. Patients were evaluated in three groups as those who received CDKi in first-line (group A, n:202), second-line (group B, n: 153) and ≥ 3rd-line (group C, n: 254). PFS was compared according to the use of ET and CT. In addition, ET was compared as monotherapy versus everolimus-based combination therapy. RESULTS: The median duration of CDKi in the ET arms of Group A, B, and C was 17.0, 11.0, and 8.5 months in respectively; it was 9.0, 7.0, and 5.0 months in the CT arm. Median PFS after CDKi was 9.5 (5.0-14.0) months in the ET arm of group A, and 5.3 (3.9-6.8) months in the CT arm (p = 0.073). It was 6.7 (5.8-7.7) months in the ET arm of group B, and 5.7 (4.6-6.7) months in the CT arm (p = 0.311). It was 5.3 (2.5-8.0) months in the ET arm of group C and 4.0 (3.5-4.6) months in the CT arm (p = 0.434). Patients who received ET after CDKi were compared as those who received everolimus-based combination therapy versus those who received monotherapy ET: the median PFS in group A, B, and C was 11.0 vs. 5.9 (p = 0.047), 6.7 vs. 5.0 (p = 0.164), 6.7 vs. 3.9 (p = 0.763) months. CONCLUSION: Physicians preferred CT rather than ET in patients with early progression under CDKi. It has been shown that subsequent ET after CDKi can be as effective as CT. It was also observed that better PFS could be achieved with the subsequent everolimus-based treatments after first-line CDKi compared to monotherapy ET.

Real-life experience of patients with sarcomatoid renal cell carcinoma: a multicenter retrospective study.

Sarcomatoid renal cell carcinoma (sRCC) is a rare variant of renal cell carcinoma (RCC) and is associated with a poor prognosis. We reviewed the outcomes of patients from oncology centers in Turkey. Our aim is to share our real-life experience and to contribute to the literature. The demographic and clinical features, treatment, and survival outcomes of 148 patients with sRCC were analyzed. The median age at the time of diagnosis was 58 years (range: 19-83 years). Most patients (62.8%) had clear-cell histology. Most patients were in the intermediate Memorial Sloan-Kettering Cancer Center (MSKCC) risk group (67.6%) and were stage 4 at the time of diagnosis (63.5%). The most common sites of metastasis were the lung (60.1%), lymph nodes (47.3%), and bone (35.8%). The patients received a median of two lines (range: 0-6) of treatment. The most common side effects were fatigue, hematological side effects, hypertension, and hypothyroidism. The median follow-up was 20.9 months (range: 1-162 months). The median overall survival (OS) was 30.8 months (95% confidence interval: 24.9-36.7 months). In multivariate analysis, high MSKCC scores, sarcomatoid differentiation rates >50%, having stage 4 disease, and having lung metastasis at the time of diagnosis were independent factors for poor prognosis affecting OS. No difference was observed between patients who received tyrosine kinase inhibitor (TKI) as the first or second-line treatments. Similarly, no difference between TKI and immunotherapy as the second-line treatment. In conclusion, sRCC is a rare variant of RCC with a poor prognosis and response to treatment. Larger-scale prospective studies are needed to define an optimal treatment approach for longer survival in this aggressive variant.

Real-Life Analysis of Efficacy and Safety of Everolimus Plus Exemestane in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor-2-Negative Metastatic Breast Cancer Patients: A Turkish Oncology Group (TOG) Study.

PURPOSE: This study evaluated the efficacy and safety of everolimus (EVE) plus exemestane (EXE) in hormone-receptor positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) metastatic breast cancer (MBC) patients in real-life settings. METHODS: Overall, 204 HR+, HER2- MBC patients treated with EVE + EXE after progressing following prior endocrine treatment were included. Overall survival (OS) and progression-free survival (PFS) and safety data were analyzed. RESULTS: The objective response rate, median PFS, and median OS were 33.4%, 8.9 months, and 23.4 months, respectively. Multivariate analysis revealed that negative progesterone receptor status was a significant determinant of poor treatment response (p = 0.035) and PFS (p = 0.024). The presence of bone-only metastasis was associated with better treatment response (p = 0.002), PFS (p < 0.001), and OS (p = 0.001). CONCLUSION: We confirmed the favorable efficacy and safety profile of EVE + EXE for HR+, HER - MBC patients.

The effectiveness and safety of neoadjuvant pertuzumab and trastuzumab in women with locally advanced, inflammatory, or early-stage human epidermal growth factor receptor 2-positive breast cancer: Turkish Oncology Group study.

In our study, we aimed to evaluate the pathological response rates and side effect profile of adding pertuzumab to the treatment of HER2+ locally advanced, inflammatory, or early-stage breast cancer. This study was conducted by the Turkish Oncology Group (TOG) with data collected from 32 centers. Our study was multicentric, and a total of 364 patients were included. The median age of the patients was 49 years (18-85 years). Two hundred fifteen (60%) of the cases were hormone receptor/HER2+ positive(ER+ or PR+, or both), and 149 (40%) of them were HER2-rich (ER and PR negative). The number of complete responses was 124 (54%) in the docetaxel+trastuzumab+pertuzumab arm and 102 (45%) in the paclitaxel+trastuzumab+pertuzumab arm, and there was no difference between the groups in terms of complete response. In 226 (62%) patients with complete response, a significant correlation was found with DCIS, tumor focality, removed lymph node, and ER status P < 0.05. Anemia, nausea, vomiting, myalgia, alopecia, and mucosal inflammation were significantly higher in the docetaxel arm, P < 0.05. In our study, no statistical difference was found between the before-after echocardiography values. DCIS positivity in biopsy before neoadjuvant chemotherapy, tumor focality; the number of lymph nodes removed and ER status were found to be associated with pCR. In conclusion, we think that studies evaluating pCR-related clinicopathological variables and radiological imaging features will play a critical role in the development of nonsurgical treatment approaches.

Real-world data on efficacy and safety of first-line alectinib treatment in advanced-stage, ALK-positive non-small-cell lung cancer patients: a Turkish Oncology Group study.

Aims: In this multicenter study, the authors aimed to determine the real-life efficacy and safety of first-line alectinib. Materials & methods: This retrospective trial included advanced-stage, ALK-positive non-small-cell lung cancer patients who were treated with first-line alectinib in terms of ALK-tyrosine kinase inhibitors, regardless of previous chemotherapy. The co-primary end points were progression-free survival both for all patients and for the treatment-naive population. The secondary end points were overall response rate, overall survival, rate of CNS progression and safety. Results & conclusion: A total of 274 patients (n = 177 for treatment-naive patients) were enrolled in the study. The median progression-free survival was 26 and 28.8 months for all patients and the treatment-naive group, respectively. The overall response rate, CNS progression rate and 1-year overall survival ratio were 77.9, 12.4 and 77%. Alectinib is a highly effective therapy with a favorable safety profile.

The advancements in cancer treatment, particularly in the last two decades, have been promising. Non-small-cell lung cancer (NSCLC) is one of the most important diseases experiencing these promising developments. ALK positivity, which is caused by the rearrangement of different gene fragments between two chromosomes, affects about 5% of NSCLC patients. This provides a target for next-generation therapies. One of these targeted therapy drugs is alectinib. The authors examined the outcomes of 271 patients with body-disseminated NSCLC who received alectinib as initial targeted therapy. These patients were not chosen to participate in a clinical phase study. They were treated with an approved drug; the study also included 97 patients who had previously received chemotherapy. The median duration of survival without disease worsening was 26 months for all patients receiving alectinib treatment. This value was 28.8 months in 177 patients who had not received any treatment before alectinib. Regardless of disease status, 77% of all patients were found to be alive at the end of the first year. Alectinib treatment resulted in a significant improvement of the disease in approximately four out of five patients. The treatment's side effects were generally tolerable or manageable. Only four patients were reported to have discontinued their medication due to treatment-related side effects. These real-world findings are compatible with previous clinical research. Alectinib is an important first-line treatment option for patients with advanced, ALK-positive NSCLC.

Prognostic factors of perioperative FLOT regimen in operable gastric and gastroesophageal junction tumors: real-life data (Turkish Oncology Group).

BACKGROUND: Perioperative FLOT regimen is a standard of care in locally advanced operable gastric and GEJ adenocarcinoma. We aimed to determine the efficacy, prognostic factors of perioperative FLOT chemotherapy in real-life gastric and GEJ tumors. METHODS: The data of patients who were treated with perioperative FLOT chemotherapy were retrospectively analyzed from 34 different oncology centers in Turkey. Baseline clinical and demographic characteristics, pretreatment laboratory values, histological and molecular characteristics were recorded. RESULTS: A total of 441 patients were included in the study. The median of age our study population was 60 years. The majority of patients with radiological staging were cT3-4N(+) (89.9%, n = 338). After median 13.5 months (IQR: 8.5-20.5) follow-up, the median overall survival was NR (95% CI, NR to NR), and median disease free survival was 22.9 (95% CI, 18.6 to 27.3) months. The estimated overall survival at 24 months was 62%. Complete pathological response (pCR) and near pCR was achieved in 23.8% of all patients. Patients with lower NLR or PLR have significantly longer median OS (p = 0.007 and p = 0.033, respectively), and patients with lower NLR have significantly longer median DFS (p = 0.039), but PLR level did not affect DFS (p = 0.062). The OS and DFS of patients with better ECOG performance scores and those who could receive FLOT as adjuvant chemotherapy instead of other regimens were found to be better. NLR was found to be independent prognostic factor for OS in the multivariant analysis. At least one adverse event reported in 57.6% of the patients and grade 3-4 toxicity was seen in 23.6% patients. DISCUSSION: Real-life perioperative FLOT regimen in operable gastric and GEJ tumors showed similar oncologic outcomes compared to clinical trials. Better performance status, receiving adjuvant chemotherapy as same regimen, low grade and low NLR and PLR improved outcomes in real-life. However, in multivariate analysis, only NLR affected OS.

Association of illness perception with chemotherapy-induced nausea and vomiting: a Turkish Oncology Group (TOG) study.

Chemotherapy-induced nausea and vomiting (CINV) may be linked to the psychological status of cancer patients. Therefore, the authors aimed to better understand the underlying risk factors for CINV using the Brief Illness Perception Questionnaire. A total of 238 patients were recruited during three cycles of chemotherapy. Patient, disease and treatment characteristics were noted at the onset of chemotherapy. The Brief Illness Perception Questionnaire was administered face-to-face prior to chemotherapy. The relationship between illness perceptions and CINV was analyzed using Spearman's rank correlation. Positive illness perception parameters, including personal and treatment control, were negatively correlated, whereas negative illness perception parameters, including consequences, timeline, identity, concern and emotions, were positively correlated with CINV after adjusting for age, sex and emetogenic potential of chemotherapy (p < 0.001). Illness perception may be an underlying risk factor for CINV.

Is SUVmax of 18F-FDG PET/CT Predictive Factor for Malignancy in Gastrointestinal Tract?

BACKGROUND: Increasing use of 18F-FDG PET/CT in cancer patients, has led to more common detection of 18F- FDG uptake in the gastrointestinal tract (GIT). AIMS: The objective of this study was to assess 18F-FDG uptake in incidental and known GIT malignancy. METHODS: A total of 6500 patients followed-up in a single and tertiary center between January 2010 and September 2016 were retrospectively reviewed. Of 2850 patients assessed with 18FDG-PET/CT, known GIT malignancy and 18F-FDG uptake cases during follow-up were included in the study. RESULTS: Of 658 patients with 18F-FDG uptake, 150 patients who underwent endoscopy were included in the study. Seventy-seven of these patients had known GIT malignancy and 73 had incidental 18F-FDG uptake. Among these 73 patients; 7 (9.6%) had malignancy, 20 (27,2%) adenoma and 24 (32.9%) inflammation that were confirmed. Endoscopy was normal in 22 (30.2%) patients. One hundred forty-three (95.3%) patients had focal and 7 (4.7%) had diffuse uptake. While no malignancy was detected in patients with diffuse uptake, 58.7% (84/143) of the patients with focal uptake presented malignancy. Mean the standardized uptake value (SUV) max values were found as 15.0 ± 10.6 (range, 3.8-56.5) in malignant disease, 10.2 ± 4.3 (range, 2.4-19.7) in adenoma, 7.3 ± 3.6 (range, 3.6-18.7) in inflammation, and 9.8 ± 4.2 (range, 3.8-19.9) in normal endoscopy groups (p < 0.001, rho = 0.378). CONCLUSION: Although this study demonstrated high probability of malignant disease with increased 18F-FDG uptake in the GIT, it would be a more appropriate approach to confirm all patients with 18F-FDG uptake through endoscopy as SUVmax values vary in a wide range.

Is the prognostic nutritional index a prognostic and predictive factor in metastatic non-small cell lung cancer patients treated with first-line chemotherapy?

PURPOSE: We aimed to assess the prognostic and predictive significance of pretreatment Onodera's prognostic nutritional index (OPNI) in metastatic non-small cell lung cancer patients (NSCLC) treated with first-line chemotherapy. MATERIALS AND METHODS: Patients with metastatic NSCLC who attended five different medical oncology clinics between December 2008 and January 2018 were retrospectively analyzed. The optimal cut-off point for OPNI was performed by a receiver operating characteristic (ROC) curve analysis. Patients were assigned to either the low OPNI group or high OPNI group. RESULTS: A total of 333 patients were included in the study. Significant differences between the low and high OPNI groups were found regarding the rates of response to chemotherapy, sex, and hemoglobin level (p < 0.05). The patients in high OPNI group had a longer overall survival (OS) (15.3 vs. 10.6 months, p < 0.001) and progression-free survival (PFS) (6.7 vs. 5.3 months, p < 0.001) compared to the patients in low OPNI group. A multivariate analysis using Cox regression model revealed that a high OPNI score was an independent prognostic factor of OS (HR = 1.535, p = 0.002) and PFS (HR = 1.336, p = 0.014), but failed to demonstrate a statistical significance of pretreatment OPNI scores in predicting treatment response (p = 0.56). CONCLUSIONS: Pretreatment OPNI is an independent prognostic factor for OS and PFS in metastatic NSCLC patients treated with first-line chemotherapy. Thus, it may be used as easily calculated and low-cost prognostic tool in the routine clinical practice in this patient group.

Biweekly cisplatin and gemcitabine with two different doses in non small cell lung cancer patients: A retrospective singlecenter experience.

PURPOSE: Non-small-cell lung cancer (NSCLC) constitutes 80-85% of all lung cancers. Patients with advanced-stage NSCLC may benefit from chemotherapy. Gemcitabine and cisplatin is a well-established therapy for this malignancy. Recently, biweekly administration is becoming more acceptable, but the most effective and tolerable dose remains unclear. The purpose of this study was to compare the toxicity and efficacy of 1000 mg/m2 gemcitabine (GEM 1000) and 1500 mg/m2 gemcitabine (GEM 1500) in combination with 50 mg/m2 cisplatin. METHODS: Gemcitabine was administered at a dose of 1000 or 1500 mg/m2 with cisplatin administered at a dose of 50 mg/m2 on day 1. The treatment was repeated every 2 weeks for a total of 4 courses. Response rates, progression-free survival (PFS), overall survival (OS) and toxicities were assessed. RESULTS: 114 patients with IIIB and IV stages of NSCLC were included. Seventy two patients (63%) received GEM 1000 and 42 (37%) received GEM 1500. The overall reponse rate (ORR), PFS and OS were 24%, 6 months and 13 months respectively in the GEM 1000 group and 36%, 6 months and 15 months in the GEM 1500 group, respectively. Grade 3-4 neutropenia and thrombocytopenia were observed in 4% of the GEM 1000 group and 9% of the GEM 1500 group (p=0.41). CONCLUSION: Biweekly administration of GEM 1000 and 1500 is a well tolerated regimen. Although the GEM 1000 group showed a lower response rate than the GEM 1500 group, PFS and OS were similar.

Comparison of anthracycline-containing and anthracycline-free regimens in neoadjuvant HER-2 positive breast cancer treatment.

While some clinics have adopted abbreviated neoadjuvant treatment for HER2-positive breast cancer, there remains a shortage of comprehensive clinical data to support this practice. This is a retrospective, multicenter study. A total of 142 patients were included in the study who are HER2-positive breast cancer, aged ≤ 65 years, with left ventricular ejection fraction ≥ 50%, received neoadjuvant chemotherapy and underwent surgery at 10 different oncology centers in Türkiye between October 2016 and December 2022. The treatment arms were divided into 4-6 cycles of docetaxel/trastuzumab/pertuzumab for arm A, 4 cycles of adriamycin/cyclophosphamide followed by 4 cycles of taxane/TP for arm B. There were 50 patients (35.2%) in arm A and 92 patients (64.8%) in arm B. The median follow-up of all of the patients was 19.9 months (95% CI 17.5-22.3). The 3-year DFS rates for treatment arms A and B were 90.0% and 83.8%, respectively, and the survival outcomes between the groups were similar (p = 0.34). Furthermore, the pathologic complete response rates were similar in both treatment arms, at 50.0% and 51.1%, respectively (p = 0.90). This study supports shortened neoadjuvant treatment of HER2-positive breast cancer, a common practice in some clinics.

Real-world data on the efficacy and safety of trastuzumab emtansine in patients with metastatic breast cancer previously treated with pertuzumab: Turkish oncology group multicenter study.

We aimed to evaluate the efficacy and safety of trastuzumab emtansine in patients with metastatic breast cancer previously treated with pertuzumab plus trastuzumab and taxane. We reviewed the medical records of patients who were diagnosed with Human Epidermal Growth Factor Receptor 2 (HER-2) positive metastatic breast cancer and received pertuzumab and then TDM-1 between January 2014 and January 2021 from twenty- five cancer centers. The Kaplan- Meier method estimated progression-free survival (PFS) and overall survival (OS). Additionally, objective response rate (ORR), clinical benefit rate (CBR), and safety were evaluated. One hundred fifty-three patients were included,79.1% of the patients received TDM-1 in the second line, 90.8% had visceral metastasis, and 30.7% had central nervous system involvement. The PFS and OS of TDM-1 were evaluated according to the number of previous lines (on the 2nd line or more than two lines) metastatic sites (visceral and non-visceral) and the presence of central nervous metastasis. In TDM-1 therapy, PFS in second line therapy was ten months (95% CI: 7.7 - 12.2); this was statistically higher than later-line PFS, which was six months (95% CI: 3.3 to 8.6) (p = 0.004). The median OS time was 25 months (95% CI: 21.0 to 28.9) in patients treated with TDM-1 in the second line and 19 months (95% CI: 12.3 to 25.6) in patients who received later than the second line(p = 0.175). There were no significant differences in PFS time of patients with and without visceral and central nervous metastases. Our study showed that TDM-1 was also effective in patients using pertuzumab, contributes significantly to PFS when used in the second line compared to its use in the later line, and does not make any difference in OS.

Efficacy of adjuvant capecitabine in residual triple negative breast cancer: a multicenter observational Turkish Oncology Group (TOG) study.

BACKGROUND: Triple negative breast cancer (TNBC) is characterized by high rates of recurrence, especially in patients with residual disease after neoadjuvant chemotherapy (NAC). Capecitabine is being used as standard adjuvant treatment in residual TNBC. We aimed to investigate the real-life data regarding the efficacy of capecitabine in residual TNBC. DESIGN AND METHODS: In this retrospective multicenter study, TNBC patients with residual disease were evaluated. Patients, who received standard anthracycline and taxane-based NAC and adjuvant capecitabine were eligible. Overall survival (OS), disease free survival (DFS) and toxicity were analyzed. RESULTS: 170 TNBC patients with residual disease were included. Of these, 62.9% were premenopausal. At the time of analysis, the recurrence rate was 30% and death rate was 18%. The 3-year DFS and OS were 66% and 74%, respectively. In patients treated with adjuvant capecitabine, residual node positive disease stood out as an independent predictor of DFS (p = 0.024) and OS (p = 0.032). Undergoing mastectomy and the presence of T2 residual tumor was independent predictors of DFS (p = 0.016) and OS (p = 0.006), respectively. CONCLUSION: The efficacy of capecitabine was found lower compared to previous studies. Selected patients may have further benefit from addition of capecitabine. The toxicity associated with capecitabine was found lower than anticipated.