MAMMARY GLAND:- Modified sweat gland.Rudimentary in males.Located in the superficial fascia.A small extension from its superolateral pa ( axillary tail of Spence) pierces deep fascia and extends into the axilla. The apeure through which the axillary tail passes into axilla is called foramen of langer. Extend: veically- 2nd to 6th ribHorizontally- lateral border of sternum to the midaxillary line. Deep relations:-Pectoral fascia 3 muscles- pectoralis major, serratus anterior, external oblique muscle of abdomen. Skin:-Covering of breast.Nipple- conical projection below the centre of the breast at the level of 4th intercostal space.Areola-circular area of pigmented skin surrounding the base of the nipple. Contains a large number of sebaceous glands. Stroma- suppoing framework. The fibrous stroma forms septa, known as the suspensory ligament of copper. Parenchyma:-It is a tubuloalveolar gland which secretes milk. The gland consists of 15 to 20 lobes. Each lobe is a cluster of alveoli and is drained by lactiferous duct. The lactiferous ducts converge towards the nipple and open on it. Near its termination, each duct has a dilation called the lactiferous sinus Aerial supply:-Internal thoracic aery.Axillary aery branches like lateral thoracic, superior thoracic and acromiothoracic.Posterior intercostal aery. Veins:-Axillary veinInternal thoracic veinPosterior intercostal vein Nerve supply:-Somatosensory- derived from 4th to 6th intercostal nerves through their anterior and lateral cutaneous branches.These nerves provide sensory innervation to the skin and carry autonomic fibres to the smooth muscles and blood vessels of the breast. Secretion is controlled by hormone prolactin. Lymph nodes:-Axillary Internal mammarySupraclavicularPosterior intercostal Cephalic REF: BD Chaurasia 7th edition page no:36.