Differences in Outcomes Between Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Metastatic Breast Cancer Patients in Upper Middle-Income versus High-Income Countries: A Retrospective Study from 4 Oncology Centers.

BACKGROUND Therapeutic options for human epidermal growth factor 2 (HER2)-positive metastatic breast cancer (mBC) are developing rapidly. This study aimed to determine the differences in the survival outcomes of patients with HER2-positive mBC in relation to access to anti-HER therapy at 3 oncology centers in upper-middle-income countries (UMICs) and 1 oncology center in a high-income country (HIC). MATERIAL AND METHODS We retrospectively identified 42 patients from Croatia (HIC), 71 patients from Serbia (UMIC), and 57 from Bosnia and Herzegovina (UMIC) diagnosed with HER2-positive mBC who were treated between January 2015 and December 2020. The pathohistological features of the tumors were obtained from the pathological findings, which were made according to standard procedures for each center. Patients were treated depending on the availability of therapy, which differed for centers in different countries. We evaluated disease-free survival, progression-free survival, and overall survival (OS) based on the availability of first- and second-line anti-HER2 therapy in UMICs vs HIC. RESULTS OS in first-line therapy was better in patients treated with dual HER2 blockade than in patients treated without dual HER2 blockade, P<0.001. OS in second-line therapy was significantly better in patients treated with trastuzumab emtansine than in patients treated with other reported regimens, P=0.004. CONCLUSIONS Results of our study showed superior survival among patients who were treated with dual first-line HER2 therapy as well as second-line trastuzumab emtansine therapy than in those patients in other centers where these drugs were not available. Raising awareness about this could help improve the situation.

Co-administration of pazopanib and enteral nutrition with omega-3 fatty acids as a safety issue in a patient treated for metastatic clear cell renal cancer: A case report.

Pazopanib is an oral multitargeting tyrosine kinase inhibitor (TKI) of vascular endothelial growth factor receptors (VEGFRs), approved as the first-line treatment of metastatic renal cell carcinoma (mRCC) and soft tissue sarcoma (STS) at a fixed dose of 800 mg daily taken fasted. Potential drug-meal interactions and adverse events (AEs) may lack recognition and the related data in literature. We report one case of stomatitis/oral mucositis associated with pazopanib administrated with an oral nutritional supplement enriched with omega-3 fatty acids. The 50-year-old patient with mRCC started pazopanib treatment at standard doses of 800 mg daily as first-line therapy for mRCC, and after a few days, he developed stomatitis. Co-administration of pazopanib with high-fat meals could increase the solubility of highly lipophilic pazopanib, increasing its plasma pazopanib area under the curve (AUC), and maximum concentration (Cmax) above optimal therapeutic level can consequently lead to increased frequency/grade of AEs.

Guidelines for breast cancer management in Bosnia and Herzegovina.

Breast cancer is the most common cancer among women. In Bosnia and Herzegovina, accurate data on the status of breast cancer are lacking due to the absence of a central registry. Multiple international guidelines imply that institutions that monitor breast cancer patients should have optimal therapeutic options for treatment. In addition, there have been several international consensus guidelines written on the management of breast cancer. Application of consensus guidelines has previously been demonstrated to have a positive influence on breast cancer care. The importance of specialty breast centers has previously been reported. As part of the 2021 Bosnian-Herzegovinian American Academy of Arts and Sciences (BHAAAS) conference in Mostar, a round table of multidisciplinary specialists from Bosnia and Herzegovina and the diaspora was held. All were either members of BHAAAS or regularly participate in collaborative projects. The focus of the consortium was to write the first multidisciplinary guidelines for the general management of breast cancer in Bosnia and Herzegovina. Guidelines were developed for each area of breast cancer treatment and management. These guidelines will serve as a resource for practitioners managing breast cancer in the Bosnia and Herzegovina region. This might also be of benefit to the ministry of health and any future investors interested in developing breast cancer care policies in this region of the world.

Prognostic and predictive significance of VEGF, CD31, and Ang-1 in patients with metastatic clear cell renal cell carcinoma treated with first-line sunitinib.

The most common type of renal cell carcinoma (RCC) is clear cell renal cell carcinoma (ccRCC), which has a high metastatic potential. Even though the International Metastatic RCC Database Consortium (IMDC) risk model is conventionally utilized for selection and stratification of patients with metastatic RCC (mRCC), there remains an unmet demand for novel prognostic and predictive markers. The goal of this study was to analyze the expression of Vascular endothelial growth factor (VEGF), Cluster of Differentiation 31 (CD31) to determine microvessel density, and Angiopoietin-1 (Ang-1) in primary kidney tumors, as well as their predictive and prognostic value in patients with metastatic ccRCC (mccRCC) who were treated with first-line sunitinib. The study included 35 mccRCC patients who were treated with first-line sunitinib in period between 2009 and 2019. Immunofluorescence was used to examine biomarker expression in tissue specimens of the primary tumor and surrounding normal kidney tissue. Median disease-free survival (DFS) was longer in patients with negative and low tumor VEGF score than in patients with medium tumor VEGF score (p=0.02). Those with low tumor CD31 expression had a longer median DFS than patients with high tumor CD31 expression (p=0.019). There was no correlation between Ang-1 expression and DFS. The expression of biomarkers in normal kidney tissue was significantly lower than in tumor tissue (p<0.001). In conclusion, higher VEGF scores and greater CD31 expression were associated with longer DFS, but neither of these biomarkers correlated with progression-free survival or overall survival.

The Oncology Association of Bosnia and Herzegovina's recommendations for fertility preservation in oncologic patients.

Malignancy is one of the major public health problems in Bosnia and Herzegovina. Along with breakthroughs in specific oncological therapy, improving the quality of life of cancer patients and management of therapy-induced side effects need to be recognized as a priority in the comprehensive cancer patient care. Fertility loss after cancer treatment is a field requiring special attention due to its various consequences on patients themselves.  Although oncofertility is well-recognized area of oncology, low- to middle-income countries are facing issues with its implementation in everyday practice. Increased awareness about fertility preservation is of high priority for all specialists who participate in the medical care of cancer patients. The absence of a systemic solution and lack of expertise led to the founding of Fertility Preservation Working Group of the Oncology Association of Bosnia and Herzegovina. We have made recommendationsas an expert consensus with the ultimate goal of making the first step towards enhancement of oncofertility implementation in Bosnia and Herzegovina.

Acceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology Clinic of University Clinical Hospital Mostar, Bosnia and Herzegovina: A Cross-Sectional Study.

BACKGROUND The pandemic of Coronavirus infectious disease 2019 (COVID-19) poses a major public health challenge, and an effective vaccine is the potential mechanism to resolve this specific situation. The present study aimed to evaluate acceptance of COVID-19 vaccination among patients attending the Oncology Clinic of University Clinical Hospital Mostar. MATERIAL AND METHODS This cross-sectional observational study enrolled 364 patients with cancer from the Oncology Clinic of University Clinical Hospital Mostar during February 2021. Data were collected using a questionnaire that captured general information about the participants and their attitudes toward COVID-19 vaccination. RESULTS Of the participants, 41.8% answered "Yes" when asked if they would take the vaccine once it becomes available, 37.6% answered "Not sure", and 20.6% answered "No". For patients in favor of vaccination, the main reasons reported were fear of getting sick (77.6%), the desire to contribute to herd immunity (57.8%), and trusting the recommendations of health professionals (57.2%). The main reasons for the patients' vaccination -refusal/indecision were doubts about the results from clinical trials of COVID-19 vaccines (49.1%), concerns about adverse effects (24.5%), and confusion about the various vaccine options (19.8%). The majority of participants (82.4%) stated that recommendation by their oncologist could influence their decision about vaccination. Of the participants who indicated unwillingness (refusal or indecision) to be vaccinated against COVID-19, 65.3% stated that recommendation by their oncologist could influence their decision about vaccination. CONCLUSIONS The findings from the present study showed most patients had refused or were indecisive regarding immunization with COVID-19 vaccine. Increasing physician awareness of this situation may result in higher rates of vaccination.

The Role of Family Physicians in the Prevention and Early Detection of Cancer in Herzegovina-Neretva and West-Herzegovina Canton.

BACKGROUND: This study aimed to investigate and analyze the role of general practitioners/family physicians (GPs/FPs) in counseling and encouraging early cancer prevention, their perception of value systems towards health and disease (especially malignant diseases), knowledge and experience with the national and local cancer early detection program. SUBJECTS AND METHODS: A cross-sectional observational study included 38 GPs/FPs from nine municipalities in the Hercegovina-Neretva and West Herzegovina canton. Data were collected by using an Individual questionnaire for all GPs/FPs which was prepared according to the Questionnaire for family physicians on implementing the Cancer Control Program, which is used in Croatia. RESULTS: Statistical analysis showed that most GPs/FPs carried out activities on primary cancer prevention (educating patients about smoking, alcohol, diet, physical activity, cancer education, and screening). The majority of respondents stated that it was not profitable to do screening for lung cancer and stomach cancer. Most GPs/FPs (73.7%) recommended mammography to women individually, sporadically, according to individual risk assessment. CONCLUSIONS: The scientific contribution and the results of this work can be applied in practice in local communities. Given its position in the health system, ongoing contact with the population that elected it, and its impact on the local community in which it operates, GP/FP plays an important role in the prevention of disease. Integration of preventive activities into the daily work of the doctor plays the most important role in achieving excellent results. Family medicine is primarily focused on primary and secondary prevention, which is carried out through a continuous approach and long-term management of patients.

Impact of COVID-19 Pandemic on Mental Health of Medical Students at the University of Mostar.

BACKGROUND: Previous studies have shown that medical students are more prone to depression, more tired, and more prone to emotional exhaustion, depersonalization and burnout syndrome than other students. In terms of mental health, they are a "more vulnerable" than individuals of the same age in the general population. In December 2019 in Wuhan (China) the outbreak of pneumonia caused by the new coronavirus captured worldwide attention. The implementation of strict quarantine measures kept a large number of people in self-isolation which affected all aspects of life. Objective of the study is to determine the direct impact of the COVID-19 pandemic on mental health and quality of life of medical students and the differences in the impact between genders and years of study. SUBJECT AND METHODS: This is a cross-sectional study conducted from May 25 to June 5 2020. It includes medical students who resided in the country affected by the COVID-19 pandemic. Participants completed a modified anonymous online questionnaire that assessed the Impact of Event Scale, indicators of negative mental health impacts, social and family support, and lifestyle changes due to a pandemic. RESULTS: The mean IES score in the participants showed a moderate stressful impact, with the mean IES score of females being significantly higher than that of males (29 vs. 19) with p<0.001. More than half of the participants had an IES score ≥26. With the onset of the pandemic, 71.5% of all medical students reported feeling increased stress from commitments. CONCLUSIONS: the pandemic had stressful impact on the mental health of medical students and it was significantly more stressful for women and students in the preclinical years of study. The COVID-19 pandemic had no impact on social and family support, however a positive impact on the lifestyle of medical students was found.

Chemobrachyradiotherapy and consolidation chemotherapy in treatment of locally advanced cervical cancer : A retrospective single institution study.

BACKGROUND: Given the lack of primary and secondary prevention programs and cancer awareness in general, cervical cancer remains one of the main causes of cancer-related death in developing countries, such as Bosnia and Herzegovina. Optimization of combinations of external radiation therapy (ERT), brachytherapy and chemotherapy is still needed to improve outcomes in the treatment of advanced cervical cancer. PATIENTS AND METHODS: We retrospectively analyzed 48 consecutive patients with Fédération Internationale de Gynecologie et d'Obstetrique (FIGO) 2009 stage IB2-IVA, who were treated with primary concomitant chemobrachyradiotherapy (CCBRT) and consolidation chemotherapy at the Department of Oncology, University Hospital Mostar, Bosnia and Herzegovina between December 2012 and June 2020. Patients were treated with ERT plus two cycles of concomitant chemobrachytherapy with ifosfamide and cisplatin and low-dose rate (LDR) brachytherapy followed by four cycles of consolidation chemotherapy at 3­week intervals. We evaluated local control rate (LCR), disease-free survival (DFS), overall survival (OS), disease-specific survival (DSS) and toxicity. RESULTS: After 45.5 months (interquartile range, IQR = 47 months) of median follow-up, 5­year DFS was 72.8% (95% confidence interval. CI 59-78%), OS was 76.6% (95% CI 60-79%), and DSS was 88% (95% CI 71-86%) with acceptable toxicity. LCR was 94%. CONCLUSION: Primary CCBRT and consolidation chemotherapy applied in standard clinical practice in the treatment of locally advanced cervical cancer (LACC) produce respectable outcomes.

Resilience and Quality of Life of Patients with Breast Cancer.

INTRODUCTION: Breast cancer is the most common malignancy in women. Modern research attempts to investigate the relationship between psychoemotional parameters and the length of survival of breast cancer patients. Understanding the factors which affect a higher level of resilience can have important clinical implications and can represent a guiding principle for designing psychological interventions that would accelerate recovery and improve the quality of life of cancer patients. To explore the relationship between resilience and quality of life of women with breast cancer. METHODS: The study was conducted at the Clinic of Oncology of the University Clinical Hospital Mostar, which included 60 subjects. Objective realization was achieved through using the socio-demographic questionnaire purposely made for this research, the quality of life questionnaire WHQOL-BREF and the psychological resilience questionnaire CD-RISC-25. RESULTS: Subjects treated with radiotherapy achieved statistically significantly higher scores on subscales of the quality of life: mental health, social relations, and the environment. No statistically significant correlations were found between the level of resilience and results in the domains of quality of life. CONCLUSION: There is not a statistically significant association between resilience levels and quality of life in patients with breast cancer.

Metastatic Malignant Melanoma Causing Small Bowel Intussusception: A Case Report with 4-year Follow-up.

Primary mucosal malignant melanoma of the small bowel is extremely rare. The small bowel is mostly affected by metastases of the primary malignant melanoma of the skin. Bowel obstruction is a rare complication of metastatic melanoma. We present a case of small bowel obstruction in a 49-year-old man with history of skin malignant melanoma. A segmental resection of the ileum with termino-terminal anastomosis was performed. Pathohistological examination showed metastatic melanoma. After 4 years of follow-up, the patient is still free of the disease.

Use of the Depression, Anxiety and Stress Scale (DASS-21) Questionnaire to Assess Levels of Depression, Anxiety, and Stress in Healthcare and Administrative Staff in 5 Oncology Institutions in Bosnia and Herzegovina During the 2020 COVID-19 Pandemic.

BACKGROUND Providing oncology services during a pandemic can contribute to mental health challenges among healthcare workers. The present study aimed to evaluate the levels of depression, anxiety, and stress in healthcare and administrative staff in 5 oncology institutions in Bosnia and Herzegovina (BiH) in 2020 during the coronavirus disease 2019 (COVID-19) pandemic using the Depression, Anxiety and Stress Scale (DASS-21) questionnaire. MATERIAL AND METHODS A cross-sectional observational study enrolled 175 healthcare and administrative workers from 5 oncology institutions in BiH during December 2020. Data were collected using a questionnaire that captured general information about the participants and a DASS-21 questionnaire. RESULTS Statistical analysis revealed a statistically significant difference in the levels of depression, anxiety, and stress (P=0.003, P=0.011, and P=0.022, respectively) among participants with comorbidities connected with increased risk of severe illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compared with participants without comorbidities. There was also a statistically significant difference in the levels of stress among participants from different cities (P=0.031). Supplement intake and educational level were significantly related (P=0.012). High levels of stress and anxiety were accompanied by high levels of depression among participants (P<0.01). CONCLUSIONS The findings from the present study showed that the COVID-19 pandemic has had an effect on depression, anxiety, and stress levels in oncology staff in BiH. Monitoring these levels and providing interventions and support to oncology staff are increasingly important for their wellbeing and retention at a time of global crisis in healthcare.

Association between Resilience and Quality of Life in Patients with Colon Cancer.

INTRODUCTION: Colon cancer is one of the most common malignancies. Numerous studies suggest an association between resilience and quality of life in colon cancer patients. The aim of this study was to explore the association between resilience and quality of life in people with colon cancer. SUBJECTS AND METHODS: A cross-sectional study was conducted on a sample of 200 subjects at the Oncology Clinic of the University Clinical Hospital Mostar. Data were collected in the period between April 2019 and June 2021. A socio-demographic questionnaire specifically designed for this study, a CD-RISC-25 scale for assessing resilience, and a WHOQOL-BREF questionnaire for assessing quality of life were used for collecting data. RESULTS: A statistically significant positive association of resilience with all domains of quality of life was found. The mental health domain contributed the most statistically significantly positively to the level of resilience. Patients who were not married had a statistically significantly higher level of resilience compared to married, divorced and widowed patients. No statistically significant difference was found in resilience levels relative to other socio-demographic factors and cancer stage. Patients treated with a combination of surgery and chemotherapy had a statistically significantly higher level of resilience compared to patients treated with other therapeutic methods. CONCLUSIONS: Higher level of resilience statistically significantly contributes to a higher level of quality of life in people with colon cancer.

The Use of Complementary and Alternative Medicine among Cancer Patients Undergoing Conventional Treatment: A Single-Centre Experience.

BACKGROUND: The alternative medicine is increasingly accepted by modern man. People realize that healing based on natural methods is much more affordable and not more aggressive than taking potent drugs of synthetic origin. The aim of this study was to collect data on the use of complementary agents and alternative medicine in cancer patients treated at the Oncology Clinic of the University Clinical Hospital in Mostar. SUBJECTS AND METHODS: We conducted a cross-sectional study that included 100 patients. Data were collected from a questionnaire compiled for this research, which comprised two groups of questions. The first group examined the sociodemographic characteristics of the respondents, and the second the modalities of using Complementary and Alternative Medicine (CAM), and health and conceptual reasons for use. RESULTS: A total of 72 patients (72.0%) had used a CAM during their anticancer treatment. Only 23% of patients had used CAM before the diagnosis of cancer. Among them, 26 (36.1%) previously discussed the topic with their oncologist. CAMs ranged from herbal medicine (58.3%), cannabinoid oil (19.4%) and different vitamins and minerals (22.2%). CAMs were mainly used to improve the health (40.3%). Among patients who used CAM only 25% find it financially demanding, 90.3% of patients were satisfied with effects of CAMs, and 78.1% would recommend it to other cancer patients. CONCLUSION: Our data showed that in our region, many patients used complementary and alternative methods of treatment. These results are very important because they provide information and give a clearer picture of the use of CAM among cancer patients and, accordingly, the right approach of the health practitioners to the patient, leading to optimized cancer therapy and increased safety.

2020 consensus guideline for optimal approach to the diagnosis and treatment of HER2-positive breast cancer in Bosnia and Herzegovina.

The HERe2Cure project, which involved a group of breast cancer experts, members of multidisciplinary tumor boards from healthcare institutions in Bosnia and Herzegovina, was initiated with the aim of defining an optimal approach to the diagnosis and treatment of HER2 positive breast cancer. After individual multidisciplinary consensus meetings were held in all oncology centers in Bosnia and Herzegovina, a final consensus meeting was held in order to reconcile the final conclusions discussed in individual meetings. Guidelines were adopted by consensus, based on the presentations and suggestions of experts, which were first discussed in a panel discussion and then agreed electronically between all the authors mentioned. The conclusions of the panel discussion represent the consensus of experts in the field of breast cancer diagnosis and treatment in Bosnia and Herzegovina. The objectives of the guidelines include the standardization, harmonization and optimization of the procedures for the diagnosis, treatment and monitoring of patients with HER2-positive breast cancer, all of which should lead to an improvement in the quality of health care of mentioned patients. The initial treatment plan for patients with HER2-positive breast cancer must be made by a multidisciplinary tumor board comprised of at least: a medical oncologist, a pathologist, a radiologist, a surgeon, and a radiation oncologist/radiotherapist.

Tumour Size Distribution of Invasive Breast Cancer in a One-Year Period: Case Study Herzegovina.

BACKGROUND: To analyse the early stage breast cancer tumour size distribution as an important prognostic factor among the female patients within our local geographic region of Herzegovina. SUBJECTS AND METHODS: This cross-sectional retrospective study included 379 patients who were treated in 2017 at the Oncology Clinic, University Clinical Hospital Mostar. The patients were divided into two groups based on their primary tumour size: early (≤2 cm) and late (>2 cm) stage groups. RESULTS: The number of patients tested for advanced stage tumours surpassing 2 cm was statistically higher (χ2=106,325; p<0.001). 39.32% (N=149) of the patients presented with tumours ≤2 cm (T1) and 52.24% (N=198) of the total number of the patients presented with tumours >2 cm but ≤5 cm in greatest dimension (T2). The patients' knowledge about breast cancer, availability and adherence of mammography did not show any statistically significant difference with regard to tumour size, while the number of patients with smaller tumours who indicated that they underwent regular mammography was statistically significantly higher (χ2=13,629; p<0.003). CONCLUSIONS: Our data shows that in our region, more women with a diagnosis of breast cancer presented with a larger tumor size. Although there was no statistically significant difference with regard to prior knowledge about breast cancer and availability to mammography, this may be due to a small sample size. Our region does not have a screening mammogram program and this data suggests that the implementation of such a program may improve adherence to existing mammography guidelines which might capture tumors at a smaller size and hence an earlier stage.

Rare Human Epidermal Growth Factor Receptor 2 (HER-2)-Positive Neuroendocrine Carcinoma of the Breast: A Case Report with 9-Year Follow-up.

BACKGROUND Neuroendocrine carcinoma of the breast (NECB) is very rare, accounting for 0.1% of all breast tumors and less than 1% of all neuroendocrine tumors. Most NECBs are hormone receptor-positive and human epidermal growth factor receptor 2 (HER-2)-negative and more than 50% are the luminal B subtype. Because prospective studies of NECB are lacking, treatment is the same as for other breast tumors. CASE REPORT A 70-year-old woman was diagnosed with NECB in February 2011. She underwent radical right mastectomy and right axillary node dissection. Final histopathological examination revealed NECB with positive axillary nodes (N1). The tumor cells were 100% positive for estrogen receptors and 10% positive for progesterone receptors. The HER-2 status was 3+. According to the Tumor, Node, Metastasis (TNM) Classification of Malignant Tumors, the pathologic stage was IIB - pT2pN1cM0. The histologic grade was 2 and the Ki-67 proliferation index was 5.7%. The patient received adjuvant chemotherapy, radiation therapy, IV trastuzumab, and endocrine therapy. After 9 years of follow-up, she remains disease-free. CONCLUSIONS As far as we know, this is only the second report describing treatment of HER-2-positive NECB with trastuzumab. A literature review shows that it is the first report of treatment of HER-2-positive primary NECB with adjuvant trastuzumab. In similar cases, long-term follow-up is recommended because of the potential for multiple metastases of NECB even years after completion of adjuvant therapy.

Correlation of Religiousness with the Quality of Life and Psychological Symptoms in Oncology Patients.

INTRODUCTION: Malignant diseases are one of the leading mortalities in the world, causing a range of psychological symptoms and reducing the quality of life in oncology patients. Examine the correlation of religion with the quality of life and psychological symptoms in oncology patients. SUBJECTS AND METHODS: The cross-sectional study included 100 oncology patients in the test group and 80 internal medicine patients in the control group. A sociodemographic questionnaire was specifically designed for this study, the Duke University Religion Index, the Symptom Check List 90, and the WHOQOL-100 quality of life assessment were used to collect the data. RESULTS: The average score in oncology patients was significantly lower on the subscales for physical health (p<0.000), social connections (p<0.002), and intrinsic religiousness (p<0.046) in comparison to internal medicine patients. On the psychological symptoms scale, the average score was higher in oncology patients with the largest difference observed on the psychoticism subscale (p<0.078). CONCLUSION: Oncology patients are statistically less religious and are not satisfied with the quality of life in comparison to internal medicine patients. Psychological symptoms are more pronounced in oncology patients but the difference is not statistically significant. A lower level of religiousness is statistically negatively correlated with a higher severity of psychological symptoms.

Strontium substituted biomimetic calcium phosphate system derived from cuttlefish bone.

Biomimetic triphasic strontium-substituted calcium phosphate (CaP) powders were prepared by wet precipitation method at 50°C, using CaCO3 , (NH2 )2 COH3 PO4 , and Sr(NO3 )2 as reagents. Calcite was prepared from biogenic source (cuttlefish bone). The synthesized powders have been characterized by elemental analysis, Fourier transform infrared spectrometry, X-ray diffraction, Rietveld refinement studies and cell viability test. Phase transformation and ion release were analyzed during 7 days of incubation in simulated body fluid at 37°C. The raw precipitated powders were composed of calcium deficient carbonated hydroxyapatite (HA), octacalcium phosphate (OCP), and amorphous calcium phosphate (ACP). After heat treatment at 1200°C ß-tricalcium phosphate (ß-TCP) was detected. Strontium substitution for calcium results in an increase of lattice parameters in HA, OCP, and ß-TCP. Sr2+ occupy the Ca(1) site in HA, Ca(3,4,7,8) sites in OCP and Ca(1,2,3,4) sites in ß-TCP. Along with Sr2+ substitution, presence of Mg2+ and Na+ ions was detected as a result of using biogenic calcium carbonate. The culture of human embryonic kidney cells indicated noncytotoxicity of the prepared CaP powders with emphasis on the cell proliferation during 3 days of culture.