{"id":{"repo_id":"varna","oai_identifier":"oai:repository.mu-varna.bg:nls/4430"},"canonical_url":"https://search.dev.ndltd.org/etd/varna/oai:repository.mu-varna.bg:nls/4430","repository":{"repo_id":"varna","name":"Medical University of Varna","base_url":"https://repository.mu-varna.bg/oai/request"},"display":{"title":"Prevalence of Pik3ca-Mutations and Response to First-Line Endocrine Therapy in a Population of Bulgarian Patients with HR(+) HER2(–) Metastatic Breast Cancer // Честотата на PIK3CA-мутацията и отговорът към първа линия ендокринна терапия в популацията от български пациентки с HR(+)HER2(-) метастазирал карцином на гърдата","abstract":"The study examined 250 patients with metastatic HR(+)/HER2(–) breast cancer, diagnosed and treated between January 2016 and November 2022 at three hospitals in Bulgaria (Nadezhda Hospital - Sofia, St. Marina University Hospital – Varna, Acibadem City Clinic Hospital Tokuda – Sofia). The prevalence of the PIK3CA mutation and its relationship to certain clinicopathological characteristics of the patients and their response to first-line therapy were investigated. The data analysis was retrospective. All patients provided histological samples for examination after signing informed consent. Some of the patients were diagnosed at the metastatic stage, while others were diagnosed at an early stage and later progressed. All patients received first-line therapy. The results showed that the PIK3CA mutation among Bulgarian patients was 29.2%, which is comparable to the frequency reported in several international studies. The study did not find a statistically significant difference in median progression-free survival and OS in first-line therapy with ET±CDK4/6 inhibitor in patients with confirmed PIK3CA mutation and those without mutation.","abstract_html":"The study examined 250 patients with metastatic HR(+)/HER2(–) breast cancer, diagnosed and treated between January 2016 and November 2022 at three hospitals in Bulgaria (Nadezhda Hospital - Sofia, St. Marina University Hospital – Varna, Acibadem City Clinic Hospital Tokuda – Sofia). The prevalence of the PIK3CA mutation and its relationship to certain clinicopathological characteristics of the patients and their response to first-line therapy were investigated. The data analysis was retrospective. All patients provided histological samples for examination after signing informed consent. Some of the patients were diagnosed at the metastatic stage, while others were diagnosed at an early stage and later progressed. All patients received first-line therapy. The results showed that the PIK3CA mutation among Bulgarian patients was 29.2%, which is comparable to the frequency reported in several international studies. The study did not find a statistically significant difference in median progression-free survival and OS in first-line therapy with ET±CDK4/6 inhibitor in patients with confirmed PIK3CA mutation and those without mutation.","abstract_has_math":false,"creators":["Gencheva, Radostina","Генчева, Радостина"],"institution":"Medical University of Varna","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2026,"date_issued":"2026-06-26T12:46:57Z","date_published":"2026-06-26T12:46:57Z","updated_at":"2026-07-27T21:56:56Z","subjects":["breast cancer","PIK3CA mutation","metastatic stage","Онкология / Oncology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://repository.mu-varna.bg/handle/nls/4430","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Gencheva, Radostina","Генчева, Радостина"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2026-06-26T12:46:57Z","2026"]},{"key":"dc:publisher","label":"Institution","values":["Medical University of Varna"]},{"key":"dc:type","label":"Dc Type","values":["thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["breast cancer","PIK3CA mutation","metastatic stage","Онкология / Oncology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://repository.mu-varna.bg/handle/nls/4430"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The study examined 250 patients with metastatic HR(+)/HER2(–) breast cancer, diagnosed and treated between January 2016 and November 2022 at three hospitals in Bulgaria (Nadezhda Hospital - Sofia, St. Marina University Hospital – Varna, Acibadem City Clinic Hospital Tokuda – Sofia). The prevalence of the PIK3CA mutation and its relationship to certain clinicopathological characteristics of the patients and their response to first-line therapy were investigated. The data analysis was retrospective. All patients provided histological samples for examination after signing informed consent. Some of the patients were diagnosed at the metastatic stage, while others were diagnosed at an early stage and later progressed. All patients received first-line therapy. The results showed that the PIK3CA mutation among Bulgarian patients was 29.2%, which is comparable to the frequency reported in several international studies. The study did not find a statistically significant difference in median progression-free survival and OS in first-line therapy with ET±CDK4/6 inhibitor in patients with confirmed PIK3CA mutation and those without mutation.","В проучването бяха изследвани 250 пациенти с метастатичен HR(+)/HER2(–) рак на гърдата, диагностицирани и лекувани в периода между януари 2016 г. и ноември 2022 г. в три болници в България (МБАЛ \"Надежда\" - София, УМБАЛ \"Света Марина\" - Варна , МБАЛ \"Токуда\"- София). Беше изследвана честотата на PIK3CA-мутацията и отношението й към някой клинико-патологични характеристика на пациентите и отговорът им към първа линия на терапия. Анализът на данните беше ретроспективен. Всички пациенти предоставиха хистологични препарати за изследване, след като подписаха информирано съгласие. Част от пациентите са диагностицирани в метастазирал стадий, а останалите в ранен стадий, но след това са прогресирали. Всички са получили първа линия на терапия.. Резултатите показаха, че PIK3CA мутацията сред българските пациенти е 29.2%, което се равнява на честотата й докладвана в няколко международни изследвания. В проучването не беше установена статистически значителна разлика в средната преживяемост без прогресия и ОП на първа линия ET ± CDK4/6-инхибитор между пациенти с доказана PIK3CA мутация и тези без мутация."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Prevalence of Pik3ca-Mutations and Response to First-Line Endocrine Therapy in a Population of Bulgarian Patients with HR(+) HER2(–) Metastatic Breast Cancer // Честотата на PIK3CA-мутацията и отговорът към първа линия ендокринна терапия в популацията от български пациентки с HR(+)HER2(-) метастазирал карцином на гърдата"]}]}],"canonical_facts":{"dc:creator":["Gencheva, Radostina","Генчева, Радостина"],"dc:date":["2026-06-26T12:46:57Z","2026"],"dc:description":["The study examined 250 patients with metastatic HR(+)/HER2(–) breast cancer, diagnosed and treated between January 2016 and November 2022 at three hospitals in Bulgaria (Nadezhda Hospital - Sofia, St. Marina University Hospital – Varna, Acibadem City Clinic Hospital Tokuda – Sofia). The prevalence of the PIK3CA mutation and its relationship to certain clinicopathological characteristics of the patients and their response to first-line therapy were investigated. The data analysis was retrospective. All patients provided histological samples for examination after signing informed consent. Some of the patients were diagnosed at the metastatic stage, while others were diagnosed at an early stage and later progressed. All patients received first-line therapy. The results showed that the PIK3CA mutation among Bulgarian patients was 29.2%, which is comparable to the frequency reported in several international studies. The study did not find a statistically significant difference in median progression-free survival and OS in first-line therapy with ET±CDK4/6 inhibitor in patients with confirmed PIK3CA mutation and those without mutation.","В проучването бяха изследвани 250 пациенти с метастатичен HR(+)/HER2(–) рак на гърдата, диагностицирани и лекувани в периода между януари 2016 г. и ноември 2022 г. в три болници в България (МБАЛ \"Надежда\" - София, УМБАЛ \"Света Марина\" - Варна , МБАЛ \"Токуда\"- София). Беше изследвана честотата на PIK3CA-мутацията и отношението й към някой клинико-патологични характеристика на пациентите и отговорът им към първа линия на терапия. Анализът на данните беше ретроспективен. Всички пациенти предоставиха хистологични препарати за изследване, след като подписаха информирано съгласие. Част от пациентите са диагностицирани в метастазирал стадий, а останалите в ранен стадий, но след това са прогресирали. Всички са получили първа линия на терапия.. Резултатите показаха, че PIK3CA мутацията сред българските пациенти е 29.2%, което се равнява на честотата й докладвана в няколко международни изследвания. В проучването не беше установена статистически значителна разлика в средната преживяемост без прогресия и ОП на първа линия ET ± CDK4/6-инхибитор между пациенти с доказана PIK3CA мутация и тези без мутация."],"dc:format":["application/pdf"],"dc:identifier":["http://repository.mu-varna.bg/handle/nls/4430"],"dc:publisher":["Medical University of Varna"],"dc:subject":["breast cancer","PIK3CA mutation","metastatic stage","Онкология / Oncology"],"dc:title":["Prevalence of Pik3ca-Mutations and Response to First-Line Endocrine Therapy in a Population of Bulgarian Patients with HR(+) HER2(–) Metastatic Breast Cancer // Честотата на PIK3CA-мутацията и отговорът към първа линия ендокринна терапия в популацията от български пациентки с HR(+)HER2(-) метастазирал карцином на гърдата"],"dc:type":["thesis"]},"updated_at":"2026-07-27T21:56:56Z"}