Clinical Anatomy of the Female Breast PDF

Clinical anatomy of the female breast A/Prof Lakal Dissabandara Objectives Describe organisation of the breast. Describe the surface anatomy relevant to breast. Describe the development of the breast and development anomalies. Describe the blood supply and ner...

Clinical anatomy of the female breast A/Prof Lakal Dissabandara Objectives Describe organisation of the breast. Describe the surface anatomy relevant to breast. Describe the development of the breast and development anomalies. Describe the blood supply and nerve supply of the breast Describe the lymph drainage of the breast. Describe the axillary group of lymph nodes. Describe the possible routes of spread of breast malignancies. Understand the anatomical basis of clinical signs associated with breast pathologies. Tissues of the Breast acini inside lobules to ductules A modified sweat gland. gland - ectodermal origin Tissues of the breast - Skin, subcutaneous fat, fasciae, Corpus mammae. Corpus mammae – Consists of Glandular Tissue & Connective tissue stroma main glandular tissue Arranged into Lobes (15-20) Each lobe consists of lobules formed by microscopic acinar and ductular elements. acini to terminal ducts Segmental ducts Lobules are drained by terminal ducts. Lactiferous sinus temporary storage of lymph Terminal ducts from multiple lobules Alveoli →Ductule → Terminal ducts drain into segmental ducts. → Segmental duct → Lactiferous Segmental ducts drain into lactiferous duct duct Each lactiferous duct has dilated sinus close to the nipple where secretions can be stored. Corpus mammae Each lactiferous duct opens separately to the exterior via the nipple. Nipple Areola complex stratified squamous and keratinised Nipple consists of skin, smooth muscle, connective tissue and the lactiferous ducts. Smooth muscle contract in response to touch, cold & sexual arousal. Areolar is the pigmented skin surrounds the Montgomery tubercles nipple. and sinus Functions Prevents drying/fissuring of the nipple glands stop drying By numerous sebaceous glands (Glands Infected Montgomery gland of Montgomery – Visible as Tubercles of Montgomery) Sensitive to hormones → Increased in size during pregnancy/lactation Contains mechanoreceptors which stimulates the secretion of oxytocin during feeding. infect - cyst and abscess formation Connective tissue/fasciae related to the breast Retro-mammary space Pectoral fascia (deep fascia) Representation of the fascial layers of the abdomen can be seen in the breast. Rib 2 Camper’s fascia is represented by the subcutaneous fat layer. Pec major Scarpa’s fascia splits into 2 layers (superficial and deep) and envelops the breast tissue. Deep fascia (Pectoral fascia) covers the pectoral muscles. superficial to the main muscles The potential space between pectoral fascia & deep lamella is the Retro- mammary space. implant of breast Consists of fat and loose areolar tissue use this term Deep layer of superficial fascia Breast freely moves over this space Neurovascular structures and some Rib 2 splits into two layers lymphatics pass through this space Superficial layer Scarpa’s fascia & subcutaneous fat of superficial fascia Camper’s fascia of Abdomen Connective tissue/fasciae related to the breast Retro-mammary space Pectoral fascia the lines of yellow conenctive tissue with spaces - forms shape (deep fascia) Connective tissue extend from the deep suspensory ligaments lamella of superficial fascia, through the Astley Cooper Rib 2 breast tissue into the dermis – Astley Ligaments Cooper ligaments (Suspensory ligaments deep layer to Pec major dermis of skin of the breast) network of connective tissue provides support Form a connective tissue shell that house the glandular and fat tissue in multiple compartments before getting attached to the skin. With aging these ligaments atrophies and stretch causing sagging of breast. Deep layer of superficial fascia Rib 2 Superficial layer Scarpa’s fascia & of superficial fascia Camper’s fascia of Abdomen  Astley Cooper ligaments multiple cavities by connective tissue providing structural stability of breast and stops hanging hormonal changes and become atrophied - leads to hanging of breast https://oncohemakey.com/ & Bille et al., 2019 Boundaries and Surface Anatomy Rib 2 Rib 2 Axillary tail Lateral sternal Pec Major border Ser Ant Rib 6 attachment Rib 6 Inframammary fold Ex Ob Rec Ab Midaxillary line Vertical Extent (Base) – 2 – 6 ribs Fascial plane – Superficial to the deep (Pectoral)fascia inf attachment Lateral border – Midaxillary line Muscles – Overlap Pec major/minor, Serratus anterior, Ex lateral sternal border to oblique and Rectus abdominis laterally mid-axillary line Medial border – Lateral sternal border Axillary tail of Spence – Extension of upper lateral part of the breast into the axilla Axillary Tail of Spence Breast tissue from the upper lateral quadrant extends through the Pec. Major deep fascia (Pectoral fascia) and under the pectoralis major muscle into the axilla. tail - differential for lump the tail is in upper lateral quadrant The tail merges with the axillary fat containing the lymph nodes. Axillary tail may be mistaken for enlarged axillary nodes! Axillary tail May be symptomatic yellow is the Experience monthly premenstrual changes: deep fascia Foramen of Tenderness and swelling Langer Difficulty with shoulder range of motion Irritation from clothing https://radiologykey.com/mammography-3/ Symptoms may intensify and become more noticeable during Pregnancy & lactation proliferation of breast tissue in pregnancy Axillary tail contains breast Pectoral fascia tissue and pathologies here Foramen of Langer deep to fascia Breast Tissue defect here extend into axilla as axillary tail of spence https://screening.iarc.fr/atlasbreastdetail.php?Index=003&e= Region of the breast (For clinical Examination) Breast is divided into regions for examination/localizing lumps. – 4 quadrants for systematic exam – axillary tail examine carefully – Nipple and areola. Upper outer quadrant has the bulk of glandular tissue → Malignancies commonly found here (Some studies 60%) Question - malignancies tend to occur in the upper outer quadrant Percentages indicate the occurrence of breast cancers in different regions of breast in this UK study. Development of the Breast -Prenatal Around 5-6 WIUL (after flexion) ectodermal very early thickening appear ventrally - Mammary Line (Mammary ridge) Mammary line extends from future axilla to the 5-6w Section (A-D) to 9-10 thigh region, along a curved line. Most of this ridge disappears (by 9-10 WIUL) Mammary Line except around 4th ICS. Remains of Around 4th ICS, Ectodermal cells, proliferate into mammary line invagination the dermis to form the 1ry & 2ry Mammary buds. around 4th ICS Canalization of the secondary mammary buds – invaginates Depressed Nipple 15-20 Lactiferous ducts (Late 2nd trimester) Mammary Pit Epidermis During 3rd trimester, surface ectodermal invagination forms the mammary pit. Cells of the mammary pit together with the underlying mesoderm (gives rise to connective tissue, smooth muscles) gives rise to the nipple. Lactife- Lactiferous ducts open into mammary pit. 1ry 2ry orus mammary mammary ducts Proliferation of connective tissue → outward growth of bud buds nipple A B C D Mesoderm Dermis 3rd trimester Birth At birth, only ductular structure is present secondary buds to future nipple proliferate inwards now canalised no alveoli at birth more ductular connective tissue nipple is often remain depressed proliferate and Ductular grow out Development of the Breast -Postnatal During the early neonatal period nipple may remain inverted (5-10%) and later (during puberty) become everted with further proliferation of mesoderm. mesoderm needs to proliferate Sometimes fibrous tissue may continue to keep the nipple inverted beyond puberty (Need surgical excision of fibrous tissue) In neonates, falling levels of estrogen/progesterone → Prolactin secretion from pituitary →parenchymal proliferation → breast enlargement + small amount of milk secretion (Witch’s milk) some proliferation of ductules and some acini Usually in 3-4 days after birth. Does not extend beyond 2 weeks. Development of the Breast -Postnatal Pre-pubertal breast is ductular – no alveoli. only ducts pre-pubertal Pre-pubertal Ductular During puberty, under the influence of oestrogen/progesterone/prolactin, Puberty & Beyond Type 1 further branching of duct system & alveoli (Type 1 and Oestrogen/Progesteron/Prolactin Lobule small 2 lobules) hormone-induced numbers rapid growth of stroma around the ducts Branching of ducts, and formation increased deposition of fat of preliminary lobules with smaller full development by about 20 years non-secretory alveoli (Type 1) Further proliferation and growth alveoli (Type 2) Type 2 With pregnancy the distal most part of ducts rapidly Lobule proliferate to form secretory acini (Type 3 lobules dominates). Pregnancy During lactation, Prolactin and Somatomamotropin Further proliferation and expansion Type 3 stimulate the epithelial cells to produce milk (Type 4 of alveoli (Es/Prog prevent secretion) Lobule lobules). start secreting (Type 3) dense breast milk Oxytocin (suckling → stimulate mechanoreceptors in tissue areolar → Oxytocin secretion from pituitary) causes Lactating Type 4 Lobule contraction of myoepithelial cells around acini to expel Alveoli start secreting due to milk. increase Prolactin (Type 4) In 5th decade the breast start to involute with during lactation reduction of fibro glandular tissue; relative increase in percentage amount of fat. Menopause hormonal changes as reduction of glandular element Involution of glandular tissue Changes of Breast tissue composition with age Breast tissue composition across different ages) Amount of Fibroglandular tissue in breast varies with age as well as from person to fat tissue increases person. In mammography fibroglandular tissue - radiopaque – (Dense) as dense material fat tissue – radiolucent (dark) So mamorgraphic (MD)density depends on amount of fibroglandular tissue Sandhu et al, 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4727830/ The visual categories associated with mammographic all have density (MD) are shown in this image → different morphological characteristics There is evidence that increased MD is associated with increased risk of breast cancer. having dense breast tissue is suggested to be related to an increased risk of breast cancer compared to women with fatty breast tissue BreastScreen Australia recognises that in the future, breast density may have a role in determining the frequency and method of an individual’s breast screening. Further research is required to investigate what this role might be, A-D increased prior to the establishment of any new approach. BreastScreen Australia density supports such research, greater discussion, and public awareness of breast small amount density. of fibrous tissue Dense breast tissue is linked to markedly reduced mammographic fibroglanular scattered glandular sensitivity to detect cancer increases Tanner stages (sexual maturity rating) of breast development Stage I (Preadolescent) - Only the nipple is elevated above the level of the chest wall. no substantial tissue Stage II - (Breast Budding) – Palpable breast tissue under the areolar a small mound along with some increased diameter of the areolae. (First pubertal sign) 10y Stage III - (Breast elevation) The breasts and areolae continue to enlarge, although they show no 11-12y separation of contour. smooth line, in same lines Stage IV - (Areolar mound) The areolae and nipple elevate above the level of the breasts and form secondary mounds with further development of the overall breast tissue. become prominent 14-15y Stage V - Mature female breasts have developed. The nipple may extend slightly above the contour of the breasts as the result of the recession of the areolae 16y+ Tanner Development of the Breast - Anomalies Most of the mammary line disappears by 9-10WIUL except around 4th ICS. give rise to breast Mammary Line Failure to regress mammary line may lead to accessory breast tissue along the added nipples mammary line (rarely outside). Polythelia Polymastia Polythelia (supernumerary nipples) Polymastia (Supernumerary breasts) Polythelia areolis (Areola only) Pseudo mamma (Nipple + Areola without added nipple no breast glandular element , Fat+) tissue added normal tissue nipple, areola - axilla to groin Axillary breast supernumerary in groin Breast in the groin Arterial supply of the breast Arterial supply is derived mainly Superior Thoracic artery from the branches of the axillary Acromio Thoracic artery artery. Lateral Thoracic artery o Lateral Thoracic A main o Superior thoracic o Pectoral Brs of the acromiothoracic artery Internal mammary artery from subclavian o Directly by 3-4 perforating Internal mammary A branches. - perforating o Indirectly by perforating brs Brs. 2nd from anterior intercostal As behind Posterior Intercostal arteries (From Posterior sternum 3-4 perforators Thoracic aorta) provides intercostal arteries reinforcement to the lateral aspect. lateral breast some, from thoracic aorta Axillary artery, parts and branches Axillary artery starts at the lateral border crosses lat border of first rib, ends at the lower border of teres major. 3 parts landmark - pec minor 1 as this is above First part - Above the pectoralis minor pec major higher 2 Superior thoracic artery Second part - Level of pectoralis minor 3 behind pec minor Thoraco-acromial trunk thyroid arteries from Lateral thoracic artery 3 arteries to breast Third part - Below pectoralis minor Subscapular artery Posterior and anterior circumflex humeral ends at teres arteries major scapula to humerus  Perforating branches of Perforating intercostal arteries Lateral branches of Thoracic internal A mammary A internal mammary A anastamose Perforating branches of internal mammary A anterior intercostals Aorta provide Posterior intercostal A perforating branches intercostal space Venous drainage of the breast Venous drainage follows the arterial supply. most o To the axillary vein via lateral thoracic vein Acromiothoracic V o To the internal mammary vein o Posterior intercostal vein Lateral thoracic V Connections to Batson’s plexus Posterior intercostal veins external outside vertebral column Internal mammary communicate with the Batson’s inside is in the column V plexus (Internal vertebral venous relat - prostate to subclavian plexus). Posterior intercostal Vs vein Through these connections breast to azygous cancer can spread into the vertebrae and the cranial cavity. Connection to the Batson’s plexus Cranial cavity via Venous sinuses collapse of L4 malignant cells enter the plexuses and spread External vertebral lead to implantation and seeding - secondaries plexus FROM BATSON'S TO CRANIAL CAVITY AND SEED drain into vertebral plexus Batson’s plexus pelvis, communicates no valves, go upwards w/ thoracic region and down Breast →Posterior intercostal Vs → Batson’s plexus → external and internal Lumbar spine and Cranial cavity plexus communication Nerve supply of the breast Sensory innervation of the breast is by the anterior and lateral cutaneous branches of 2nd to 6th intercostal nerves. similar to breast location T2-6 sensory and motor Nipple and areolar are mainly innervated by the 4 intercostal nerve. sensitive mixed th posterior primary ramus and skin over vertebral column 2nd to 6th rib intercostal nerve anterior primary ramus lateral cutaneous and anterior terminal branch 2 branches supply breast tissue Lymph Drainage of the Breast parenchyma Superficial tissues (skin + SCT) drained by superficial lymphatics – Subdermal and most into the Subcutaneous (See next slide) yellow lines Infraclavicular subareolar plexus Nipple, Areola and glandular tissue are drained by Infraclavicular deep lymphatics running along the lactiferous Apical ducts and the glands → Subareolar plexus and areola drain nipple and areolar for nipple Central There are numerous connections between deep and superficial lymphatics. can go superficial and deep Rotter’s Posterior Irrespective of the location, most of the breast tissue and skin drain into axillary group via medial Anterior Subareolar Plx and lateral collecting lymphatics. AXILLARY NODES DRAIN ABOUT 70% OF THE Medial BREAST – Anterior (Pectoral) group drains the bulk drain medially internal mammary of lymph. medial and lateral collecting groups axillary breast most of drain into axillary nodes Assessment of involvement of Axillary nodes Medial collecting is important for staging of breast cancer. Lateral collecting route Smaller proportion of deep lymphatics drains route directly to internal mammary / interpectoral / along internal mammary blood vessels apical /central nodes/posterior can drain into different nodes intercostal nodes. Superficial lymphatics communicates with connected to opposite side glandular towards areola lymphatics of the opposite breast and abdomen. Deep lymphatics from Superficial (Subdermal Subareolar Plx Very rarely lymph can pass into abdominal cavity glandular tissue and Subcutaneous skin of breast tissue through diaphragm. not common secondaries in peritoneal cavity lymphatics Lymphatics and lymphatic plexuses in the breast Dermal Lymphatics project in dermis Subcutaneous Lymphatics subcutaneous plexus Deep Lymphatics Mariani, G & Moresco, Luciano & Viale, Giuseppe & Villa, Giuseppe & Bagnasco, M & Canavese, Giuseppe & Buscombe, J. & Strauss, H.W. & Paganelli, Giovanni. (2001). Radioguided Sentinel Lymph Node Biopsy in Breast Cancer Surgery. Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 42. 1198-215. Axillary lymph nodes: Groups and Relations Anterior (Pectoral Group) along the lateral thoracic... Supraclavicular anterior - main nodes – Along the lateral thoracic vessels – Lateral border of the pec minor (Under Pec major – Anterior axillary Axillary Vein fold) deep and palpate R. Lymphatic duct Posterior Group Lateral – Along the subscapular/thoracodorsal Central deeply behind vessels (Under the posterior axillary sternum Internal mammary fold) along these veins nodes Lateral Group Posterior go under free very laterally – Along axillary vein in proximal upper limb border of pec major Anterior Central Group Pectoralis minor – Along axillary vein deep to the Pec Rotter’s minor all drain into central group behind this muscle Pectoralis major Apical Group Subareolar plexus – Along the axillary vein above the Pec minor Rotter’s Node (Interpectoral) between the two muscles Axillary lymph nodes: Surgical levels Surgically axillary node groups are divided in to 3 levels Supraclavicular Level 3 based on the relationship to Pec minor Axillary Vein Central Group – Level 1 - Below/lateral to Pec minor Infraclavicular Level 1 Level 2 Level 2 3 together Lateral Group Anterior, Posterior & Lateral groups below or lateral to pec minor – Level 2 – At the level of Pec minor Axillary Vein Subscapular vessels Central & Interpectoral (Rotter’s) LateralPosterior Group – Level 3 - Above/medial TOP to Pec minor Apical deepest Central All level 1 nodes drain into Central group and then into the Apical Anteri Apical nodes before draining to the thoracic duct/Right Group Posterior Latera Lymphatic duct. central -> apical -> lymphatic/thoracic duct vessel Anterior Metastatic involvement of lymph nodes usually occurs in a stepwise manner 1 → 2 → 3. skip can happen very rare Pectoralis minor LNs draining UL mostly drain into Lateral axillary group. Rotter’s These UL draining nodes are generally located on the Pectoralis major superior aspect of the axillary vein stay medial or inferior to axillary veins Subareolar plexus as primarily drain upper limb By removing nodes on the inferior aspect of the vein → minimize chances of lymphoedema of UL. Axillary lymph nodes: palpation Supraclavicular Level 1 Level 2 Level 3 Axillary VeinCentral Group upper limb to palpate Lateral Group Central Group Infraclavicular Apical Grou Lateral Proximal UL AxillaryLateral Vein Subscapular Group vessels Apical Group Central Rotter’S Node deep into LateralPosterior Group apex Deep in the axilla Pectoral – Along Central anterior axillary fold palpate along anterior axillary border Apical Anterior (Pectoral Posterior behind pec major very difficult to palpate Group) Along Posterior Group Posterior Rotter's Node under pec major to palpate Lateral Thoracic posterior vessels axillary Anterior fold Pectoralis minor lat dorsi and serratus anterior Anterior (Pectoral Rotter’s Group) Pectoralis major Subareolar plexus Axillary lymph nodes: Neural Relations Axillary nodes are related to multiple nerves. 2nd intercostal space, intercostal nerve - supplies upper limb Intercostobrachial (Supplies axillary skin), pectoral (Supplies Pectoral muscles), Long thoracic (supplies serratus anterior) and Thoracodorsal nerves (supplies Latissimus dorsi) can be damaged during axillary node dissection. anterior group of nodes long thoracic - serratus anterior; thoracodorsal - lat dorsi Potential sequalae of axillary lymphadenectomy includes lymphoedema of upper limb, sensory & Motor dysfunction in UL. spread malignancy - neurological L2-3 nodes damage nerves 2nd rib fix scapula against chest wall lateral thoracic vessels and anterior groove Detection of Sentinel Lymph Node in Breast cancer Sentinel node biopsy done when there is no clinical Peritumoral or US evidence of enlarged axillary LNs (Clinical node negative Pts). peritumoural injection This procedure helps find the first group of node Subareolar draining the breast tissue (tumour bearing area). Use Gamma Help minimise unnecessary removal of axillary probe to detect nodes. Or look for stained node Most commonly (90-95%) sentinel node of breast cancer is located in the axilla → Anterior group. Detected by injecting a dye/radioisotope material to detect node affected – subareolar plexus* drain all lymph from breast tissue track nodes – peritumoral During surgery stained/radioactive node removed for histopathology. Axillary lymphadenectomy (usually level 1,2) is considered if the sentinel node is positive for detect which nodes in lateral group drain upper limb malignant deposits. inject dye into upper limb, dye taken up and map nodes (There is increased evidence of effectiveness of radiotherapy without axillary reverse axillary clearance in positive sentinel node biopsy cases) Anatomy of clinical signs suggestive of breast malignancies Puckering of the breast Infiltration of Cooper’s malignancy or inflammation ligaments →shortening → Puckering of the breast tissue and skin invagination of skin shorten and pull in dermis Cooper’s ligs Nipple retraction Infiltration of the lactiferous Lump ducts and connective tissue Lactiferous duct & connective →shortening → retraction of tissue nipple pull nipple inwards - shorten lactiferous ducts Anatomy of clinical signs suggestive of breast malignancies Fixation of lump when contracting the muscles may be Cooper’s ligs indicative of spread of malignancy into deeper tissues (e.g. Lump Pectoral muscle) fixed - infiltrate muscle tissue spread to pectoral - fixation Lactiferous duct & contract muscle tissue connective tissue Subtle changes can only be seen by – raising the ULs → Stretch the skin of the breast – pressing their hands firmly into their hips and bring the shoulders forward to contract pec major. Look for prominence of lump increased puckering of skin increased nipple retraction asymmetry of breasts Anatomy of clinical signs suggestive of breast malignancies Peau d’ orange Appearance ( Orange peel ) Blockage of the dermal lymphatics → oedema of the skin → Deepens the openings of hair follicles and sweat/sebaceous fluid accumulates glands. blockage of lymphatics outward with fluid orange appearance Axillary masses can be sign of malignancy Lymphatic spread orange peel axillary tail or secondary axillary node... Which of the following is TRUE regarding retro-mammary space? a. Located between pec minor and major is anterior b. Lies anterior to the pectoral fascia B c. Lies posterior to the pectoral fascia too deep d. Completely avascular plane e. Used to place breast implants in past, yes but not common The main sources of arterial blood to breast include: a. Internal mammary A and posterior intercostal not main As b. Anterior intercostal As and posteriornotintercostal from internal mammary main As c. Anterior intercostal arteries and Acromiothoracic A D d. Lateral thoracic artery and Internal mammary A e. Acromiothoracic A and Superior thoracic A A surgeon is performing sentinel node biopsy procedure in a patient with breast cancer without palpable axillary nodes. Which of the following statement is correct? anterior along lateral thoracic a. Injected dye is most likely present in a node under the pectoralis minor L2 nodes b. Injected dye is most likely present in a node along the axillary vein 3 veins central L2 not common c. Injected dye is most likely present in a node along the posterior subscapular vein d. Injected dye is most likely present in a node along the lateral thoracic vein D major vein of breast  True/False a. Attachment of the breast tissue extends from the level of 2nd rib to 6th rib. T b. Cooper’s ligaments are attached to the pectoral fascia and deep lamella dermis. F c. Venous drainage of breast exclusively reach the axillary vein F internal mammary, subclavian, azygous d. Absence of enlarged axillary nodes excludes the possibility of lymphatic spread of breast cancer F can have skipping and internal mammary e. Medial quadrants of the breast exclusively drains to the internal mammary chain. Medial F and lateral into axillary This patient presented with a breast lump. Describe the findings A, B and C. You ask the patient to press his hands against the invade orange peel hip and you find that lump become fixed. Explain. pec muscles What is “A” due to? Axillary examination reveals no lymphadenopathy. For sentinel node study, a dye was injected into the subcutaneous tissue around the areola, Why? subareolar plexus Histopathology reveals adenocarcinomatous deposits in pectoral nodes. What is the location of pectoral nodes? lateral border of pec minor and along lateral thoracic vessels Pt. undergoes modified radical mastectomy with Level 2 axillary clearance. What is level 2 axillary What is “C” due to? nipple rectraction clearance. Rotter and central, L1 nodes anterior, posterior, rotter and central What is “B” due to? subcutaneous Post Op – She develops lymphoedema of right UL puckering oedema and sensory loss in the right armpit. Explain. Cooper ligament involvement upper limb drains, damage to upper lymphatics damage nerve stops drainage - blockage have sensory loss intercostobrachial nerve lesion A 53-year-old woman undergoes right sided mastectomy with level 3 axillary clearance. She presents 3 months after the surgery complaining of weakness of the right shoulder. Her husband mentions about asymmetry in her shoulder blades. Describe the findings. Explain. Long thoracic nerve instability Supply serratus anterior Shoulder movement - medial border against wall cannot fix against scapula winging of scapula damage by spread of breast cancer locally A 29-year-old woman presented with bilateral, axillary lumps noticed after her first pregnancy. She reports increasing size and tenderness of the lumps, most prominently around her menses. She was initially treated for presumed hidradenitis without any improvement. Examination reveals bilateral firm, non-tender subcutaneous lumps with nodularity. What are the differential diagnoses? Axillary tail of spence Pseudomamma Polymastia Exclude malignancy Lipoma Sebaceous cyst Identify A - D A - pec minor B - superior thoracic artery C- thoracoacromial trunk A D- lateral thoracic artery B C D Identify A-B. Damage to “A” would lead to a. Sensory loss in axilla B long thoracic to b. Scapula winging B A serratus anterior c. Paralysis of latissimus dorsi d. Shoulder abduction weakness A - long thoracic nerve for serratus anterior B - intercostobrachial nerve into axilla LATERAL CUTANEOUS branch of 2nd intercostal nerve