Hematology embriology & Anatomy Amboss Q&A
A 70-year-old man with right-sided renal cell carcinoma comes to the physician because of shortness of breath for 1 month. Yesterday he had an episode of hemoptysis. He appears cachectic and chronically ill. There is dullness to percussion and decreased breath sounds throughout both lung fields. A CT scan of the chest and abdomen shows multiple pulmonary nodules. A CT scan of the abdomen is shown. This patient's tumor most likely spread via which of the following labeled structures? Renal cell carcinoma metastasizes via hematogenous and lymphatogenous spread. Hematogenous spread is usually via the venous system.
C Option C on this axial CT scan corresponds to the inferior vena cava (IVC). Venous drainage from the right kidney enters the right renal vein and flows into the IVC. By this route metastatic renal cell carcinoma (RCC) cells could be transported via the IVC to the right heart and from there into the lungs, causing this patient's pulmonary symptoms and pulmonary nodules on CT.
A 76-year-old woman comes to the physician for a 3-day history of swelling and redness of her left lower leg. She has type 2 diabetes mellitus and hypertension. Her temperature is 38.7ºC (101.7ºF). Examination of the left leg shows an erythematous, raised skin lesion with sharply demarcated margins. The affected skin is warm and tender to palpation. A diagnosis of cutaneous streptococcal infection is made. In addition to the upper dermis, the patient's condition is most likely to involve tissue that is derived from which of the following embryological structures? Erysipelas is typically caused by group A streptococci and, as seen here, manifests with an erythematous and sharply demarcated skin lesion and possibly fever. This condition is a superficial skin infection that is limited to the upper dermis and the superficial cutaneous lymphatics.
Mesoderm The mesoderm gives rise to blood vessels and lymphatic vessels, including the superficial cutaneous lymphatics, which are affected in this patient with erysipelas. Other structures that are derived from the mesoderm are bones (except skull bones), muscles, connective tissue, certain organs (e.g., spleen, kidneys, adrenal cortex, gonads), the upper vagina, the serosal linings of body cavities (peritoneum, pericardium, and pleura), the notochord, the pachymeninges (dura mater), and microglial cells.
A 32-year-old man comes to the emergency department because of a wound in his foot. Four days ago, he stepped on a nail while barefoot at the beach. Examination of the plantar surface of his right foot shows a purulent puncture wound at the base of his second toe with erythema and tenderness of the surrounding skin. The afferent lymphatic vessels from the site of the lesion drain directly into which of the following groups of regional lymph nodes? An infection on the anteromedial thigh would also drain into this group of lymph nodes.
Superficial inguinal The superficial inguinal lymph nodes directly drain lymph from the skin below the umbilicus, including the lower back, perianal region, and most of the lower extremity with the exception of the posterior calf and the dorsolateral foot, which drain into the popliteal lymph nodes. An infection in the medial and plantar region of the foot, as seen in this patient, can result in lymphadenopathy of the superficial inguinal nodes. Lymph from the superficial inguinal nodes would drain into the deep inguinal nodes, which, in turn, drain into the external iliac nodes.
