INTRODUCTIONBreast cancer is the second leading cause of cancer death among women. The surgical treatment is the best choice for those patients. 1 Since the first mastectomy which was carried out by Halsted in 1882, surgeons have faced several problems such as skin flaps necrosis, wound breakdown, seroma, infection, nerve injuries, lymphedema, phantom breast syndrome and hematoma. Seroma, which is a subcutaneous collection of serous fluid, is a common problem in breast surgery where it develops under the skin flaps during mastectomy or in the axillary dead space after axillary dissection. It usually resolves within a few weeks, so many surgeons view this problem as an unavoidable nuisance rather than a serious complication. 3Seroma formation is the most frequent postoperative complication after breast cancer surgery. Incidence of seroma formation after breast surgery varies between 2.5% and 51%. Although seroma is not life threatening, it can lead to significant morbidity (e.g. flap necrosis, wound dehiscence, predisposes to sepsis, prolonged recovery period, multiple physician visits) and it may delay adjuvant therapy.1 The pathogenesis of seroma has not been fully elucidated. It has been hypothesized that seromas form as an exudate from an acute inflammatory ABSTRACT Background: Seroma is one of the most common morbidity occurring post modified radical mastectomy (MRM). It can delay post-operative initiation of adjuvant therapy. This study was designed to determine the role of fibrin glue spray in reduction of seroma volume and duration after breast surgeries. Methods: A prospective, randomized, controlled study over forty female patients who underwent (MRM) was done. The study cohort was randomized into control group where only conventional drain placement was used and experimental group where double dose of fibrin glue has been sprayed to the axillary and mammary beds plus conventional drain placement. Data regarding the amount of drained fluid in the first post-operative day, hospital stay, length of drain placement, amount and duration of post-operative seroma, number of excised lymph nodes (L. Ns) and pathological results were recorded. Results: No difference in mean age, number of excised L. Ns and rate of post-operative infection between both groups was detected. There was significant reduction in hospital stay time favouring fibrin glue group (p=0.006). Fibrin glue group had a significant reduction in the length of drain placement (p=0.001). The amount of postoperative serous fluid was reduced and the incidence of occurrence of post-operative seroma was (7/20) 35% in control group compared to (1/20) 5% in fibrin glue group giving significant reduction in incidence and amount. Conclusions: Use of fibrin glue sealant during MRM resulted in noticeable and significant decrease of post-operative rate of seroma formation, its amount and the length of drain placement.