en عمومى General پژوهشي Research Abstract Background: Breast carcinoma is the most common cancer in females , its incidence increase with age . The aim of this study is to analyses the biological features of breast carcinoma in postmenopausal women . Methods: Our study included 68 postmenopausal patients who underwent modified radical mastectomy in King Hussein Medical Center during the period between January 2012 and December 2014. We divided our patients into two groups : the first group was 46 Young postmenopausal patients ( YPM ) their ages from 50 to 64 years. The second group consisted of 22 elderly postmenopausal patients ( EPM ) who were 65 years of age and above . Results: Both age groups ( YPM and EPM ) had the same range of tumor size which is 2 cm and above.Tumor size was found in 80 % and 81 % respectively . YPM patients were found to have greater lymph node involvement 76 % in comparison to EPM which was 63 % . They also showed that the incidence of peritumor vascular invasion in YPM is 60 % while in the EPM patients is 50 %.Both age groups showed similar Estrogen and Progesterone receptor expression 80 % and 77 % respectively . Conclusion: Although both groups showed almost the same range of tumor size , older patients were found to have tumors with more favorable biologic characteristics in comparison to younger age group in regard to lymph node involvement and peritumor vascular invasion . Tumor responsiveness to hormonal therapy was similar in both groups . Breast cancer , Biologic features , Postmenopausal women 329 332 http://intjmi.com/browse.php?a_code=A-10-1-107&slc_lang=en&sid=1 Hani M. kafaween 10031947532846002501 10031947532846002501 No Specialist General and Oncoplastic breast surgeon ,King Hussein Medical Center Lina Al Nahar 10031947532846002502 10031947532846002502 No Specialist Histopathologist , King Hussein Medical Center, Jordan Rami Gsous 10031947532846002503 10031947532846002503 No Specialist Anesthesia , King Hussein Medical Center, Jordan Danya Alsakarneh 10031947532846002504 10031947532846002504 No Registered nurse in breast unit - King Hussein Medical Center, Jordan Ghaith Gsous 10031947532846002505 10031947532846002505 Yes Resident of General Surgery , King Hussein Medical Center, Jordan Dima Jreisat 10031947532846002506 10031947532846002506 No Resident of General Surgery , King Hussein Medical Center, Jordan