Page 1 of 21 Dr. RAJENDRANвЂ™S INSTITUTE OF MEDICAL EDUCATION FMGE MARCH 2012 - QUESTIONS AND ANSWERS GENERAL SURGERY 1) In which thyroid carcinoma is FNAC not useful? a. Medullary carcinoma b. Follicular carcinoma c. Papillary carcinoma d. Lymphoma Ans: (b) FNAC cannot distinguish between a benign follicular adenoma and follicular carcinoma. This distinction is dependent on capsular and vascular invasion. www.medicinemcq.com Page 2 of 21 T YPES OF THYROID CANCER Papillary adenocarcinoma Papillary adenocarcinoma accounts for 85% of cancers of the thyroid gland. The tumor usually presents as a solitary nodule. It then spreads via intraglandular lymphatics within the thyroid gland and then to the subcapsular and pericapsular lymph nodes. Follicular adenocarcinoma Follicular adenocarcinoma accounts for 10% of malignant thyroid tumors. Microscopically, follicular carcinoma may be difficult to distinguish from normal thyroid tissue. Capsular (invasion through the capsule) and vascular invasion distinguish follicular carcinomas from follicular adenomas. Malignancy is defined by the presence of capsular and vascular invasion. Capsular or vascular invasion cannot be determined via FNAC. Therefore, preoperative clinical diagnosis of follicular thyroid cancer is difficult unless distant metastases are present. HГјrthle cell carcinoma is a variant of follicular carcinoma. Medullary carcinoma Medullary carcinoma accounts for approximately 7% of malignant tumors of the thyroid. It contains amyloid and is a solid, hard, nodular tumor. Medullary carcinomas arise from parafollicular cells of the ultimobranchial bodies or C cells. It does not take up radioiodine and secretes calcitonin. Undifferentiated carcinoma This rapidly growing tumor occurs principally in women beyond middle life and accounts for 1% of all thyroid cancers. It is a solid, quickly enlarging, hard, irregular mass diffusely involving the gland and often invades the trachea, muscles, and neurovascular structures. Microscopically, there are three major types: giant cell, spindle cell, and small cell. Mitoses are frequent. Cervical lymphadenopathy and pulmonary metastases are common. FINE -NEEDLE ASPIRATION CYTOLOGY (BIOPSY) FNAC is the single most important test in the evaluation of thyroid masses. Ultrasound guidance is recommended for nodules that are difficult to palpate and for cystic or solid-cystic nodules that recur after the initial aspiration. www.medicinemcq.com Page 3 of 21 A 23-gauge needle is inserted into the thyroid mass. See figure below. Several passes are made while aspirating the syringe. The slides are stained by Papanicolaou's or Wright's stains and examined under the microscope. If a bloody aspirate is obtained, the patient should be repositioned in a more upright position and the biopsy repeated with a finer (25- to 30-gauge) needle. After FNAB, the majority of nodules can be categorized into the following groups: benign (65%), suspicious (20%), malignant (5%), and nondiagnostic (10%). The incidence of falsepositive results is about 1% and false-negative results occur in approximately 3% of patients. If a biopsy is nondiagnostic, it should be repeated. Capsular or vascular invasion cannot be determined via FNAC. Malignant Tumors of the Thyroid. CURRENT Diagnosis & Treatment: Surgery, 13e > Chapter 16. Thyroid & Parathyroid > Diseases of the Thyroid Malignant Thyroid Disease. Schwartz's Principles of Surgery > Chapter 38. Thyroid, Parathyroid, and Adrenal > Thyroid www.medicinemcq.com Page 4 of 21 2) False about achalasia cardia: a. Bird beak appearance b. Absent air bubble in stomach c. Decreased lower oesophageal sphincter tone d. Absent peristalsis in the body of oesophagus Ans: (c) ESOPHAGEAL ACHALASIA Achalasia is a chronic, incurable disease characterized by incomplete or absent relaxation of the LES and aperistalsis of the esophageal body. These abnormalities lead to impaired propulsion of food with consequent stasis in the esophagus. See figure below. Achalasia is seen with equal frequency in men and women. www.medicinemcq.com Page 5 of 21 The pathophysiology of achalasia is linked to the destruction of ganglion cells present in the esophageal wall and LES, which impairs the relaxation of the LES. This destruction of ganglion cells is associated with an inflammatory response. Symptoms and signs Dysphagia is the most common symptom, experienced by virtually every patient. It is often for both solids and liquids. Regurgitation of undigested food is the second-most common symptom and is present in about 60% of patients. It occurs more often in the supine position and may lead to aspiration. Heartburn is present in about 40% of patients. It is not due to gastroesophageal reflux, but rather to stasis and fermentation of undigested food in the distal esophagus. Chest pain also occurs in about 40% of patients, due to esophageal distension, and it is usually experienced at the time of a meal. Imaging studies A barium swallow should be the first test performed in the evaluation of a patient with dysphagia. It usually shows narrowing at the level of the gastroesophageal junction. Up to 95% of patients with achalasia will have a positive barium swallow. In a positive study, an aperistaltic esophagus is observed with tapering of the distal esophagus to the characteristic вЂњbirdвЂ™s beakвЂќ at the level of the esophageal hiatus. In addition, a dilated esophagus is usually seen, along with undigested food particles. See figure below. Barium swallow showing typical findings of achalasia: dilated aperistaltic esophagus, beaklike narrowing (arrow) near gastroesophageal junction, and slow emptying of barium into the stomach. www.medicinemcq.com Page 6 of 21 After a barium swallow has been performed, esophageal endoscopy should be performed to evaluate the patient for other causes of esophageal obstruction, such as esophageal cancer, which is known to be more prevalent in achalasia patients. Esophageal manometry Esophageal manometry is the key test for establishing the diagnosis of esophageal achalasia. The classic manometric findings are (1) absence of esophageal peristalsis and (2) hypertensive LES (in about 50% of patients) that relaxes only partially in response to swallowing. Achalasia. CURRENT Diagnosis & Treatment: Surgery, 13e > Chapter 20. Esophagus & Diaphragm > The Esophagus Achalasia. Beck WC - Surg Clin North Am - October, 2011; 91(5); 1031-1037 3) What percentage of total body surface is represented by whole hand burns? a. 1% b. 9% c. 18% d. 27% Ans: (a) вЂњRULE OF NINES вЂќ FOR CALCULATING BURN AREA The "Rule of Nines" can be used to estimate total burned body surface area, with each of the following representing 9%: head, anterior chest, anterior abdomen, each arm, anterior of each leg, and posterior of each leg. The back and buttocks represent 18%, while the groin and each palm represent 1%. See figure below. www.medicinemcq.com Page 7 of 21 4) Swelling that does not move with deglutition: a. Thyroglossal cyst b. Thyroid swelling c. Branchial cyst d. Tuberculous lymph nodes Ans: (c) Thyroid gland swellings and thyroglossal cysts typically move up with swallowing. Branchial cyst and tuberculous lymph nodes do not move up with swallowing. Tuberculous and malignant lymph nodes, when they become fixed to the larynx or trachea, may also move on deglutition. www.medicinemcq.com Page 8 of 21 BRANCHIAL CLEFT CYSTS Branchial cleft cysts are the most common congenital cause of a neck mass. Branchial cleft cysts are congenital epithelial cysts. They arise on the lateral part of the neck from a failure of obliteration of the second branchial cleft in embryonic development. CLINICAL FEATURES Many branchial cleft cysts are asymptomatic. They most frequently present in late childhood or early adulthood, when the cysts become infected, usually after an upper respiratory tract infection. They may become tender, enlarged, or inflamed, or they may develop abscesses, especially during periods of upper respiratory tract infection, due to the lymphoid tissue located beneath the epithelium. A branchial cyst commonly presents as a solitary, painless mass in the neck of a child or a young adult. A history of intermittent swelling and tenderness of the lesion during upper respiratory tract infection may exist. Spontaneous rupture of an abscessed branchial cleft cyst may result in a purulent draining sinus to the skin or the pharynx. Discharge may be reported if the lesion is associated with a sinus tract. DIAGNOSIS Branchial cysts can usually be differentiated from thyroglossal duct cysts by their characteristic lateral location in the neck. They occur along the lower one third of the anteromedial border of the sternocleidomastoid muscle between the muscle and the overlying skin. Ultrasonography helps to delineate the cystic nature of these lesions. Thyroglossal duct cysts located off the midline could be mistaken for branchial cleft cysts, as their sonographic appearances are similar. A contrast-enhanced CT scan shows a cystic and enhancing mass in the neck. It may aid preoperative planning and identify compromise of local structures. www.medicinemcq.com Page 9 of 21 CT scan - Branchial cleft cyst (*) Ma, masseter; M, mandible; Mp, medial pterygoid; PPS, parapharyngeal space. Fine-needle aspiration may be helpful to distinguish branchial cleft cysts from malignant neck masses. T REATMENT Surgical excision is definitive treatment for branchial cleft cysts. Branchial cleft cyst surgery is best delayed until the patient is at least age 3 months. Branchial Cleft Cysts. CURRENT Diagnosis & Treatment in OtolaryngologyвЂ”Head & Neck Surgery, 3e > Chapter 27. Neck Masses > Congenital Neck Masses T HYROGLOSSAL DUCT CYST Anatomy The duct disappears by the eighth week of gestation. Rarely, the thyroglossal duct may persist in whole, or in part. Thyroglossal duct cyst is a cystic remnant along the course of the thyroglossal duct between the foramen cecum of the tongue and the thyroid bed in the neck. It occurs as a result of anomalous development and migration of the thyroid gland during the fourth through eighth weeks of gestation. www.medicinemcq.com Page 10 of 21 Thyroglossal duct cysts may occur anywhere along the migratory path of the thyroid although 80% are found in juxtaposition to the hyoid bone. See figure below. Lingual thyroglossal duct cysts are rare, accounting for 1-2% of all thyroglossal duct cysts. Histologically, thyroglossal duct cysts are lined by pseudostratified ciliated columnar epithelium and squamous epithelium, with heterotopic thyroid tissue present in 20% of cases. Thyroid carcinomas in thyroglossal duct cysts The types of thyroid carcinoma in descending order of frequency are papillary (80%), mixed follicular-papillary, squamous, follicular, anaplastic and Hurthle cell carcinoma. Presence of calcifications in papillary carcinomas is one of the key imaging findings indicative of malignancy in thyroid ductal carcinoma. Clinical features About 50% of patients present before 20 years of age, but a significant percentage (15%) present after 50 years of age. They are usually asymptomatic. Occasionally they become infected by oral bacteria. www.medicinemcq.com Page 11 of 21 The diagnosis usually is established by observing a 1- to 2-cm, smooth, well-defined midline neck mass that moves upward with protrusion of the tongue. See figure below. Thyroglossal duct cyst - Midline neck mass that occur off the midline may be difficult to differentiate from branchial cleft cysts. A pathognomonic sign on physical examination is vertical motion of the mass with swallowing and tongue protrusion, demonstrating the intimate relation to the hyoid bone. Diagnosis Ultrasound Ultrasound imaging is used to confirm the clinical diagnosis and identify the presence of the thyroid gland. Presence of calcifications in papillary carcinomas is one of the key imaging findings indicative of malignancy in thyroid ductal carcinoma. Computed Tomography Computed tomography has a high degree of diagnostic accuracy for thyroglossal duct cysts. The thyroglossal duct is intimately related to the hyoid bone, and CT depicts this relationship best in hyoid lesions. See 2 figures below. www.medicinemcq.com Page 12 of 21 Arrow shows cystic swelling CT scan of thyroglossal duct cyst (between the arrows) CT better evaluates the potential for thyroglossal duct carcinoma and is thus preferred in adult patients. See figure below. In adults, CT is the preferred modality because the risk of carcinoma is substantially higher in adults, and CT can better identify the suggestive features of malignancy. www.medicinemcq.com Page 13 of 21 MRI Magnetic resonance imaging provides a high degree of diagnostic accuracy for thyroglossal duct cysts, but it is rarely required for the diagnosis. MRI is preferred for lesions at or near the tongue base. Treatment The вЂњSistrunk operationвЂќ is the standard method of thyroglossal duct cyst excision. The "Sistrunk operation" consists of en bloc cystectomy and excision of the central hyoid bone to minimize recurrence. Since thyroid carcinomas can be present in a small percentage of thyroglossal duct cysts, all thyroglossal cysts and tracts should undergo a careful histologic examination. Approximately 1% of thyroglossal duct cysts are found to contain cancer, which is usually papillary (85%). Thyroglossal Duct Cyst and Sinus. Schwartz's Principles of Surgery > Chapter 38. Thyroid, Parathyroid, and Adrenal > Thyroid > Developmental Abnormalities Thyroglossal Duct Cysts. CURRENT Diagnosis & Treatment in OtolaryngologyвЂ”Head & Neck Surgery, 3e > Chapter 27. Neck Masses > Congenital Neck Masses 5) Prostatic carcinoma commonly arises from: a. Central zone b. Peripheral zone c. Transitional zone d. None of the above Ans: (b) www.medicinemcq.com Page 14 of 21 PROSTATE GLAND The prostate is located in the pelvis just inferior to the bladder. See figure below. The normal prostate weighs about 20 g and contains the posterior urethra, which is about 2.5 cm in length. The prostate is divided into 3 zones: (1) transition zone, (2) central zone, and (3) peripheral zone. See figure below. Of prostate cancer cases, 70% arise in the peripheral zone, 15-20% arise in the central zone, and 10-15% arise in the transitional zone. The prostate consists of branched tubuloacinar glands organized into three layers. Around the prostatic urethra is the transition zone containing mucosal glands. Surrounding most of that zone is the intermediate central zone, which contains the submucosal glands. The outermost and largest layer is the peripheral zone, which contains the most numerous main glands. www.medicinemcq.com Page 15 of 21 The peripheral zone of the prostate constitutes 70% of the glandular tissue. This zone covers the posterior and lateral aspects of the prostate. The peripheral zone is the area that is palpated on digital rectal examination and represents the area where 70% of adenocarcinomas are found (95% of prostate cancers are adenocarcinomas). This area is also the location most commonly affected by chronic prostatitis. The periurethral portion of the gland increases in size during puberty and after the age of 55 years due to the growth of nonmalignant cells in the transition zone of the prostate that surrounds the urethra. Prostate Gland. JunqueiraвЂ™s Basic Histology, 13e > Chapter 21. The Male Reproductive System > Accessory Gland Prostate Gland. Smith's General Urology > Chapter 1. Anatomy of the Genitourinary Tract Anatomy and Pathology. Harrison's Online > Chapter 95. Benign and Malignant Diseases of the Prostate 6) Not a predisposing factor for penile carcinoma: a. Paget's disease b. Genital warts c. Circumcision d. Leucoplakia Ans: (c) www.medicinemcq.com Page 16 of 21 PENILE CARCINOMA Circumcision Circumcision has been well established as an effective prophylactic measure for penile cancer. Penile cancer is almost never observed in individuals who are circumcised in the neonatal period. The disease is found more frequently when circumcision is delayed until puberty. Adult circumcision offers little or no protection. Leukoplakia Leukoplakia is a rare condition that most commonly occurs in diabetic patients. A white plaque typically involving the meatus is seen. Leukoplakia has been associated with squamous cell carcinoma. Histologic examination reveals acanthosis, hyperkeratosis, and parakeratosis. This lesion may precede or occur simultaneously with penile carcinoma. Human papillomavirus (HPV) infection Penile cancer in men and cervical cancer in women have been associated with HPV infection. Venereal warts Viral lesions include condyloma acuminata, which are soft papillomatous growths. They have a predilection for the genital and perineal regions. These lesions are usually sexually transmitted and are caused by HPV. Giant condylomata acuminata are cauliflower-like lesions arising from the prepuce or glans. These lesions may be difficult to distinguish from well-differentiated squamous cell carcinoma. www.medicinemcq.com Page 17 of 21 Condylomata acuminata Lichen sclerosis, also known as balanitis xerotica obliterans, is a chronic lymphocytemediated skin disease that can develop on any cutaneous surface and has been associated with squamous cell carcinoma of the penis. Penile intraepithelial neoplasia is considered to be premalignant, but only 5-15% of these lesions evolve into invasive squamous cell carcinoma. Cigarette smoking and chewing tobacco are also considered to be a risk factors. Penile trauma, usually consisting of small tears or abrasions involving the prepuce, and a history of chronic balanitis are also risk factors for carcinoma. No firm evidence indicates that smegma acts as a carcinogen. Smith's General Urology > Chapter 23. Genital Tumors > Tumors of the Penis The MD Anderson Manual of Medical Oncology, 2e > Chapter 35. Penile Cancer > Causes of Penile Cancer > Human Papillomavirus www.medicinemcq.com Page 18 of 21 7) Sequence of changes seen in Raynaud's disease is: a. Red, blue, white b. White, blue, red c. Red, blue, white d. White, red, blue Ans: (b) R AYNAUD PHENOMENON (RP) Raynaud phenomenon is a syndrome of paroxysmal digital ischemia, most commonly caused by an exaggerated response of digital arterioles to cold or emotional stress. The initial phase of Raynaud phenomenon is mediated by excessive vasoconstriction. It consists of welldemarcated digital pallor or cyanosis. See 2 figures below. The subsequent (recovery) phase of Raynaud phenomenon is caused by vasodilation. It leads to intense hyperemia and rubor. Raynaud phenomenon chiefly affects fingers. It can also affect toes and other acral areas such as the nose and ears. Raynaud phenomenon www.medicinemcq.com Page 19 of 21 RaynaudвЂ™s phenomenon of the hands characterized by paroxysmal bilateral digital pallor and cyanosis followed by rubor. Raynaud disease Raynaud phenomenon is classified as primary (idiopathic or Raynaud disease) or secondary. Primary Raynaud phenomenon is especially common in young women, and poses more of a nuisance than a threat to good health. In contrast, secondary Raynaud phenomenon is less common, is chiefly associated with rheumatic diseases (especially scleroderma), and is frequently severe enough to cause digital ulceration or gangrene. See figure below. www.medicinemcq.com Page 20 of 21 Raynaud Phenomenon. CURRENT Medical Dx & Tx > Chapter 20. Rheumatologic & Immunologic Disorders > Autoimmune Diseases 8) Marjolin's ulcer predisposes to: a. Basal cell carcinoma b. Squamous cell carcinoma c. Adenocarcinoma d. Round cell carcinoma Ans: (b) www.medicinemcq.com Page 21 of 21 M ARJOLIN'S ULCERS The term Marjolin's ulcer is often used to describe neoplastic transformation (highly aggressive squamous cell cancer) in chronic ulcers. Marjolin's ulcers commonly occur in burn scars that were not skin grafted and were left to heal secondarily. See figure below. Marjolin's ulcers can also develop from previously traumatized and scarred tissue of other etiologies such as chronic sinuses of osteomyelitis, post-traumatic wounds, pressure sores and chronic fistulae. Marjolin's ulcer A high index of suspicion is required in the management of chronic non-healing ulcers and all suspected lesions should be biopsed. The possibility of malignant transformation should be considered in pressure ulcers that are unresponsive to treatment or show morphologic changes indicative of malignancy. Malignancies (Marjolin's Ulcers). Fitzpatrick's Dermatology in General Medicine, 8e > Chapter 100. Decubitus (Pressure) Ulcers > Complications http://www.wjso.com/content/10/1/38 For the rest of the 12 questions in General surgery with explanatory answers, click вЂ�premium contentвЂ™ at the top of the homepage. www.medicinemcq.com