Pathology Notes

Practice question answers Tumor of heart and vessels © Jun Wang, MD, PhD 1. C. A hypocellular tumor with scattered stromal cells without significant atypia in an edematous/myxoid background is most likely myxoma . Angiosarcoma is the most common malignant tumor of heart, and is characterized anastomosing vessels with endothelial atypia. Mucinous adenocarcinoma has atypical epithelial cells in mucin pools, not myxoid background. Papillary fibroelastoma is characterized by a papillary growth with central dense fibrous cores surrounded by loose connective tissue, not myxoid background. Rhabdomyoma is characterized by sharp demarcation and “spider cells”. 2. A. This is a case of Carney complex , presented with Cushing syndrome due to adrenal cortex hyperplasia and cardiac myxoma. Horner syndrome is caused by interruption of the sympathetic nerve supply to the eye, presents with triad of miosis, partial ptosis and loss of hemifacial sweating. Superior vena cava syndrome is...

Practice question II Tumors of heart and vessels © Jun Wang, MD, PhD 1. A 59-year old woman presents with dyspnea for 3 weeks. She denies fever, chill or weight loss. She has a history of mucinous adenocarcinoma of left breast that was treated with surgery and chemotherapy 3 years ago. Her past history is otherwise unremarkable. She does not smoke cigarette nor drink alcohol. Physical examination revealed no significant abnormalities.   Transthoracic echocardiography reveals a 2.2 cm pedunculated mass in her left atrium. The mass is removed and microscopically it has scattered mildly atypical round to oval nuclei in an edematous background. Thrombus is seen on the surface. Immunohistochemistry studies reveal no cytokeratin expressing cells. What is the most likely diagnosis? A. Angiosarcoma B. Metastatic mucinous breast cancer C. Myxoma D. Papillary fibroelastoma E. Rhabdomyoma 2. Use this case for the next two questions . A 27-year-old woman presents with o...

Practice question I answers Tumor of vessels © Jun Wang, MD, PhD 1. C. Proliferation of capillaries without cytological atypia is most likely capillary hemangioma . Angiosarcoma is characterized anastomosing vessels with endothelial atypia. Bacillary angiomatosis has neutrophilic infiltrate, and Gram negative rods can be identified by special stains. Hemangioblastoma is usually found in central nervous system, and is composed of proliferation of vessels with stromal cell atypia . Kaposi sarcoma is spindle cell tumor with slit spaces and red blood cell extravasation, usually seen in immunocompromised patients. 2. D. This is a capillary hemangioma that commonly regress with aging. There is no risk of metastasis or invasion. Malignant transformation or sepsis due to local ulceration of benign hemangioma is very rare. 3. C. Tumor with largely dilated vessels without atypia is most likely cavernous hemangioma . Angiosarcoma is characterized anastomosing vessels with en...

Practice questions I Tumors of vessels © Jun Wang, MD, PhD 1. A 2-year-old girl presents with a rapidly growing reddish mass on her left face, covering eye-lid, left side of nose, and upper lip. The mass has small foci of ulceration. Purulent exudates are seen. Microbiology culture of the purulent exudates grows non-hemolytic white raised colonies gram-positive, coagulase-negative cocci that form clusters. These bacteria are sensitive to novobiocin. Biopsy of the lesion reveals packed small channel-like spaces lined by benign flat epithelial cells that is positive for CD31. Scattered neutrophilic and lymphoplasmacytic infiltration is seen. What is the most likely diagnosis? A. Angiosarcoma B. Bacillary angiomatosis C. Capillary hemangioma D. Hemangioblastoma E. Kaposi sarcoma 2. A 1-year-old boy presents with an ulcerated lesion on his right ear. The lesion is a 2.5 cm well-demarcated, red nodule with peripheral telangiectasia and central ulceration. No other abn...

Gardner syndrome   Updated: 03/02/2021 © Jun Wang, MD, PhD General features A variant of familial adenomatous polyposis Clinical presentations Numerous colon polyps Mesentery fibromatosis Bone osteomas Fibromas Epidermal cysts , etc Genetic abnormalities APC Back to intestinal tumors Back to syndromes Back to contents

Neurofibromatosis I   Updated: 03/29/2020 © Jun Wang, MD, PhD General features Also called von Recklinghausen disease, NF1 Either autosomal dominant or de novo mutation 5 - 13% develop malignant peripheral nerve sheath tumor 2 - 4 x increased risk of other tumors (childhood CML , ganglioneuroma, meningioma, pheochromocytoma, rhabdomyosarcoma ); acoustic neuroma (schwannoma) , astrocytoma, gastric carcinoid, GIST , glomus tumor , lipoma , optic nerve glioma, Wilm tumor Clinical presentations Multiple neurofibromas (plexiform, solitary) Plexiform neurofibromas relatively specific 6 or more cafe au lait spots over nerve trunks Lisch nodules (pigmented iris hamartomas, majority by age 6) Pathogenesis Neurofibromin defect Resulted in ineffective conversion of RAS to inactive form Genetic abnormality Mutation of NF1 (neurofibromin) at chromosome 17q11.2 Back to soft tissue tumors Back to syndromes Back to contents

Neurofibromatosis II Updated: 03/29/2020 © Jun Wang, MD, PhD General features Also known as NF2, acoustic neurofibromatosis Autosomal dominant Clinical presentations Bilateral acoustic neuromas ( schwannomas ) Multiple meningiomas Spinal cord ependymomas Schwannosis (ingrowth of Schwann cells into cord) Meningioangiomatosis Glial hamartia Café au lait NO Lisch nodules (unlike NF1 ) Pathogenesis Abnormal activation of PI3K, RAS and RAC by mutated merlin Genetic abnormality Loss of function mutation of merlin at 22q12 Back to soft tissue tumors Back to syndromes Back to contents

Carney syndrome   Updated: 10/22/2020 © Jun Wang, MD, PhD General features Autosomal dominant syndrome More common in female Clinical presentations Myxomas of the skin , heart , breast, and other sites Pigmented skin/mucosa lesions Multiple endocrine tumors Primary pigmented nodular adrenocortical disease Growth hormone–producing pituitary adenomas Tumors of the thyroid gland,  Psammomatous melanocytic schwannomas Testicular Sertoli-cell tumors Genetic abnormalities PRKAR1A Back to cardiovascular system tumors Back to syndromes Back to contents

Practice questions answers Soft tissue tumors ©Jun Wang, MD, PhD 1. A. Lipoma is histologically identical to normal adipose tissue, with the exception of either grossly or microscopically identified fine fibrous capsule. Both myxoid liposarcoma and well differentiated liposarcoma will have lipoblasts, cells with multiple intracellular vacuoles and enlarged irregular hyperchromic nuclei. Recurrently carcinomas have features of previous carcinomas, either atypical squamous cells with intercellular bridges or keratin pearl for squamous cell carcinoma, or irregular glands for adenocarcinoma. 2. E. Presence of adipose tissue is highly suggestive of adipose tissue differentiation. Well differentiated liposarcoma is characterized by mature adipose tissue containing lipoblasts. All adipose tissue is positive for S-100. Mucinous carcinomas are positive for cytokeratin, and usually have recognizable mucin-producing epithelial cells. Melanomas can mimic anything, but they are po...