Chronic pain after Mastectomy is frequent and an important healthcare priority because of its effect on quality of life. Although the association between the severity of acute pain after surgery and the likelihood of chronic pain is known, their causal relationship has not been clarified. Mastectomy, frequently done for the management of breast cancer, is associated with significant acute postoperative pain and limited shoulder movement.

General anesthesia with postoperative NSAI D and opioids is a commonly used technique for postoperative analgesia after breast surgeries. Patients with mastectomy under general anesthesia commonly have pain in the axilla and upper limb that increases hospital stay, costs, and postoperative complications .Thoracic paravertebral block can be performed for analgesia after breast surgery. Ultrasound usage gave an accurate reading of the depth to the paravertebral space and can be used during the whole technique. Breast surgery is usually done with axillary dissection and can be done at single or multiple levels of thoracic paravertebral blocks .Thoracic paravertebral block is associated with multiple complications such as hypotension, pneumothorax, sympathetic block, central spread of local anesthesia or failed block which may cause limitations in the technique. The use of ultrasound in anesthesia increases the success rate of the block and decreases the incidence of variable complications .On the other hand, many interfascial plane blocks have been described. Pectoral nerve block (PECS) has been described as interfascial plane blocks and provide analgesic adjuvants for breast surgery with or without axillary dissection. The block was described as an injection of local anesthetic between the pectoralis major and minor muscles (PEC I) and between pectoralis minor and serratus anterior muscle (PEC 2) .

Inclusion Criteria:

• ASA grade I, II, or III female patients in the age group of 20-65 years
• with body mass index (BMI) of 25-35 who were undergoing mastectomy with or without axillary lymph node or sentinel lymph node dissection or partial mastectomy (sparing the skin, areola, and nipple) with axillary lymph node dissection

Exclusion Criteria:

• male sex; patient refusal,
• a life expectancy less than 2 yr;
• active malignant disease; pregnant or breastfeeding women;
• bilateral surgery; ipsilateral breast surgery in the past 3 yr;