⁨أسئلة المحاضرة التاسعة باثولوجي CVS (قبل التعديل) ⁩

Cardiac Tumors

• Primary cardiac tumors are rare and mostly benign.
• The most common benign cardiac tumors are myxomas, fibromas, lipomas, papillary fibroelastomas, and rhabdomyomas, accounting for 80-90% of all primary heart tumors.
• Myxomas are the most frequent in adults, usually located in the left atrium.
• Myxomas are composed of stellate cells embedded in an acid mucopolysaccharide ground substance.
• Rhabdomyomas are the most common primary cardiac tumors in infants and children, frequently associated with tuberous sclerosis.
• Rhabdomyomas appear as gray-white masses, characterized by large, rounded, or polygonal cells containing glycogen-laden vacuoles.
• Cardiac metastases can occur by direct extension, bloodstream, lymphatics, and intracavitary diffusion.
• Pericardial metastasis is the most common.

Pericardial Diseases

• Hemangiomas are benign tumors composed of vascular channels filled with blood cells or lymph.
• They are the most common vascular tumor of the head and neck in infancy.
• Hemangiomas are typically present from birth and may eventually regress spontaneously.
• Lymphangiomas are benign lymphatic counterparts of hemangiomas, occurring predominantly in head, neck, and axillary subcutaneous tissues.
• Kaposi sarcoma, frequently observed in HIV patients, is a malignant endothelial neoplasm associated with Kaposi sarcoma herpesvirus (KSHV).
• Kaposi sarcoma lesions progress through three stages: patch, plaque, and nodule.
• Angiosarcoma is a malignant endothelial neoplasm of variable differentiation, ranging from well-differentiated tumors resembling hemangiomas to highly aggressive lesions.
• Angiosarcoma predominantly affects older adults and can occur at any site, with a predilection for skin, soft tissue, breast, and liver.

Pericardial Diseases - Causes

• Pericardial diseases can be caused by a variety of factors, including trauma, drugs, heart tumors, systemic lupus erythematosus (SLE), uremia, radiotherapy, and hypothyroidism.

Cardiac Myxoma

• Most common primary tumor of the adult heart.
• 90% are atrial, 80% of those are in the left atrium.
• Usually single.
• Commonly found in the fossa ovalis (atrial septum).
• Can be sessile or pedunculated.
• Appears soft, translucent, villous, gelatinous.
• Consists of multinucleated stellate cells embedded in an abundant acid mucopolysaccharide ground substance.
• Clinically manifests as a "ball-valve" obstruction of the valves, embolization, or constitutional symptoms such as fever and malaise.
• Surgical resection is curative in nearly all cases.

Rhabdomyomas

• Most common primary heart tumor in infants and children.
• Frequently discovered due to valvular or outflow obstruction.
• Commonly found in patients with tuberous sclerosis.
• Appear as gray-white masses up to several centimeters, protruding into ventricular chambers.
• Characterized by large, rounded, or polygonal cells with numerous glycogen-laden vacuoles, separated by strands of cytoplasm running from the cell membrane to the nucleus, known as 'spider cells'.

Teratomas

• Second most common cardiac tumor in infants.
• Typically arise from the pericardium.
• Usually benign.
• Rarely recur.

Cardiac Metastasis

• Can occur through:
  • Direct extension.
  • Bloodstream.
  • Lymphatics.
  • Intracavitary diffusion.
• Pericardial metastasis is the most common.

Hemangiomas

• Benign vascular tumor.
• Common in infants and childhood.
• Often regresses spontaneously.
• Occurs in the head and neck, but can be more extensive (angiomatosis) and found internally.
• 1/3 of internal lesions are found in the liver.
• Types:
  • Capillary hemangiomas: most common, composed of thin-walled capillaries with minimal stroma.
  • Juvenile hemangiomas: extremely common in newborns, often multiple, grow rapidly for a few months then fade by 1-3 years, completely regress by 7 years in most cases.
  • Cavernous hemangiomas: large, dilated vascular channels, more infiltrative, frequently involve deep structures, don't spontaneously regress.

Lymphangiomas

• Benign lymphatic counterpart of hemangiomas.
• Types:
  • Simple lymphangiomas: slightly elevated, up to 1-2 cm in diameter, common in the head, neck, and axillary subcutaneous tissue, composed of networks of endothelium-lined spaces.
  • Cavernous lymphangiomas (cystic hygromas): fluid-filled sac in the neck or axilla of infants, large (up to 15 cm), composed of massively dilated lymphatic spaces lined by endothelial cells and separated by connective tissue stroma containing lymphoid aggregates.

Kaposi Sarcoma

• Caused by Kaposi sarcoma herpesvirus (KSHV, or HHV-8).
• Common in HIV patients.
• Progresses through three stages:
  • Patch stage: pink, red, or purple macules, confined to distal lower extremities.
  • Plaque stage: larger violaceous patches, raised plaques.
  • Nodular stage: accompanied by nodal and visceral involvement, plump proliferating spindle cells in the dermis or subcutaneous tissues.

Angiosarcoma

• Malignant endothelial neoplasms.
• Range from highly differentiated to anaplastic.
• Most common in older adults.
• No sex predilection.
• Lesions occur anywhere, most common in skin, soft tissue, breast, and liver.
• Aggressive, invasive, and metastasizes.
• Can arise in the setting of lymphedema, classically after radical mastectomy.
• Begins as small, asymptomatic red nodules, developing into fleshy, red-tan to gray-white masses, blending with surrounding structures.
• Necrosis and hemorrhage are common.

Pericarditis Causes

• Trauma.
• Drugs.
• Heart tumors.
• Systemic lupus erythematosus (SLE).
• Uremia.
• Radiotherapy.
• Hypothyroidism.