ABSITE 2026 Quick Hits: Breast, Endocrine, and Abdominal Wall Surgery Review

Breast Surgery Nerve Injuries

• 💡 The most commonly injured nerve in breast surgery is the intercostal brachiocutaneous nerve, affecting inner arm sensation.
• ⚠️ Injury to the long thoracic nerve can lead to a classic winged scapula due to innervation of the serratus anterior.
• 🎯 The thoracodorsal nerve innervates the latissimus dorsi, and its injury causes weak arm adduction and internal rotation.
• 📌 The medial pectoral nerve innervates both pectoralis major and minor, while the lateral pectoral nerve only innervates the pectoralis major.

Breast Cancer Diagnosis and Treatment

• 🔍 Bassin's plexus is implicated in the direct hematogenous spread of breast cancer to the spine.
• 🟢 Green discharge is typically associated with fibrocystic changes, while bloody discharge often indicates an intraductal papilloma.
• ⚠️ Unilateral discharge always warrants breast imaging due to a higher association with malignancy.
• 📈 LCIS is a marker for increased cancer risk, not premalignant itself, and usually doesn't require re-excision even with positive margins, except for the pleomorphic subtype.
• 🎯 DCIS is premalignant and requires a 2mm margin for lumpectomy, followed by radiation therapy if breast-conserving surgery is performed.
• 🏥 For palpable masses, ultrasound is the first-line imaging for patients under 30, while mammograms are standard for those over 30, augmented by ultrasound.
• 📊 Breast cancer screening recommendations typically involve annual mammograms starting around age 40-45.
• 🦴 Breast cancer most commonly metastasizes to the bone.
• 💊 Hormone therapy differs: SERMs (tamoxifen, raloxifene) for premenopausal patients and aromatase inhibitors (anastrozole, letrozole) for postmenopausal patients.
• 🚀 Neoadjuvant treatment is indicated for inoperable primary tumors, locally advanced disease, inflammatory breast cancer, large tumors with desire for breast conservation, and early-stage triple-negative breast cancer.
• ✂️ Surgical options for primary breast tumors include breast-conserving therapy (lumpectomy with post-op radiation) and mastectomy.
• 📍 Lymph node management involves sentinel lymph node biopsy for clinically node-negative patients, with axillary lymph node dissection reserved for three or more positive nodes or large primary tumors.
• 🌟 Adjuvant therapy includes chemotherapy, radiation, hormone therapy, and anti-HER2 therapy based on tumor characteristics.
• 🩸 Stewart-Treves syndrome is a lymphangiosarcoma of the upper extremity following axillary lymph node dissection.
• 📊 The BI-RADS classification system ranges from 0 (inconclusive) to 6 (biopsy-proven malignancy), guiding further imaging and biopsy decisions.
• 🤰 In pregnant patients undergoing sentinel lymph node biopsy, technetium radioactive injectable can be used, but blue dye should be avoided.

Abdominal Wall Hernias

• 📍 A Périt hernia occurs between the latissimus dorsi, external oblique, and iliac crest.
• 📌 A Spigelian hernia is located lateral to the rectus abdominis, typically below the arcuate line.
• 🎯 The Rüsch-Risdon hernia involves a small piece of bowel, specifically the anti-mesenteric side, stuck in a hernia.
• ⚠️ An incarcerated Richter's hernia involves a portion of the anti-mesenteric side of the bowel.
• 💡 Latreille's hernia is an incarcerated Meckel's diverticulum within a hernia.
• 🚀 Grynfeltt's hernia is an upper lumbar hernia bordered by the 12th rib, erector spinae muscles, and the posterior border of the inferior oblique.
• 🌟 The most common solid or omental tumor is a metastasis.

Endocrine System Disorders

• 🧬 Congenital Adrenal Hyperplasia (CAH) has three main types: 21-hydroxylase deficiency (most common, salt wasting, virilization), 11-beta-hydroxylase deficiency (not salt wasting, virilization), and 17-alpha-hydroxylase deficiency (not salt wasting, ambiguous genitalia).
• 🧪 Cushing syndrome workup involves verifying hypercortisolism (24-hr urine cortisol, salivary cortisol, low-dose dexamethasone suppression test), localizing the source (serum ACTH, high-dose dexamethasone suppression test), and imaging (MRI head, CT chest).
• 🏥 The most common cause of Cushing syndrome is iatrogenic, followed by pituitary adenomas (Cushing's disease) and adrenal adenomas.
• 💊 Drugs that inhibit steroid formation include ketoconazole and metyrapone.
• ☢️ The Wolff-Chikoff effect is the paradoxical inhibition of TSH by Lugol's solution or potassium iodide.
• 📈 Metastatic papillary thyroid cancer in a patient under 55 is typically Stage II disease.
• 🎯 Papillary thyroid cancer, the most common type, is treated with thyroid lobectomy for small, low-risk tumors or total thyroidectomy for larger, higher-risk tumors.
• 📍 For differentiated thyroid cancers, surgical approaches vary based on tumor size and characteristics, with lobectomy preferred for unilateral intrathyroid tumors <1cm, and total thyroidectomy or lobectomy for 1-4cm tumors.
• 🔪 Neck dissections are performed for clinically positive nodes or extra-thyroid involvement, with central dissection for central nodes and combined central/lateral for lateral node involvement.
• 🧪 Radioactive iodine therapy is considered for residual disease, positive lymph nodes, or capsular invasion, typically 6 weeks post-surgery.
• 🔬 Thyroglobulin levels are monitored for thyroid cancer recurrence after total thyroidectomy.
• 💀 Medullary thyroid cancer is associated with MEN2, secretes calcitonin, and is treated aggressively with total thyroidectomy and central neck dissection.
• 🧩 MEN1 includes parathyroid adenomas, pituitary adenomas (prolactinomas), and pancreatic tumors (gastrinomas).
• 🎯 MEN2A includes parathyroid hyperplasia, medullary thyroid carcinoma, and pheochromocytomas.
• 🚀 MEN2B includes medullary thyroid carcinoma, pheochromocytomas, mucosal neuromas, and marfanoid habitus.
• 🩸 The inferior thyroid artery supplies all four parathyroid glands.
• ⚖️ PTH increases calcium and decreases phosphate, while Vitamin D increases both calcium and phosphate absorption.
• 🥇 Primary hyperparathyroidism is typically caused by a parathyroid adenoma.
• 🥈 Secondary hyperparathyroidism is seen in renal failure, leading to increased PTH production.
• 🥉 Tertiary hyperparathyroidism occurs after prolonged secondary hyperparathyroidism, where parathyroids remain overactive even with improved kidney function.
• 📍 Undescended parathyroid glands are most commonly found in the thymus.
• ⏱️ PTH has a half-life of 10 minutes, crucial for intraoperative monitoring criteria.

Splenic Issues

• 📏 The normal length of the spleen on ultrasound is less than 13 cm.
• 🩸 Howell-Jolly bodies are nuclear remnants in erythrocytes, and their presence after splenectomy suggests an aberrant spleen.
• ⚠️ Hienz bodies are associated with oxidized hemoglobin, seen in conditions like thalassemia or G6PD deficiency.
• 💉 For ITP, first-line treatment is steroids, followed by IVIG, and then splenectomy if refractory. Vaccinations (Hib, meningococcal, pneumococcal) should be given prior to splenectomy.
• ⏳ Vaccines for elective splenectomy should ideally be given two weeks prior.
• 🧬 Hereditary spherocytosis is a common indication for splenectomy, usually performed after age 5.
• 🏥 Other indications for splenectomy include autoimmune hemolytic anemia, TTP, and lymphoma.