Hem n Onc 8-6 (5) Flashcards
The most common causes of cancer death in men by percentage of total deaths due to cancer are: Lung (102 per 100,000) Prostate (70 per 100,000) Colorectal (44 per 100,000) Liver cancer is ?
the fourth most common cause of cancer death in men (9.5 per 100,000), and among Asian and Pacific Islander men is it the second most common cause of cancer death. Testicular cancer is a relatively rare cause of cancer death in men, accounting for only about 0.6% of male cancer deaths.
In men, the most common causes of cancer (not cancer death) by estimated new cases per year are: prostate cancer, followed by lung and then colorectal cancer.
This patient presents after 3 weeks of fever and weight loss and exhibits pallor, hepatomegaly, and splenomegaly. These symptoms, along with her laboratory test results, are consistent with hemophagocytic lymphohistiocytosis (HLH), which is confirmed by the bone marrow aspiration, demonstrating hemophagocytes. Hemophagocytes (red arrow in image) are macrophages that have engulfed red blood cells (RBCs) and lymphocytes. Familial-type HLH is an autosomal recessive defect in several genes, including perforin-related genes, whereas the secondary type is frequently due to?
infection with Epstein-Barr virus. HLH involves the abnormal activation and proliferation of lymphohistiocytes, leading to hemophagocytosis and the upregulation of proinflammatory cytokines. The immune system becomes overstimulated and can begin attacking native cells in the bone marrow (as seen in the image in the vignette), the liver, and brain. Treatment consists of a combination of etoposide, corticosteroids, and methotrexate, although stem cell transplantation is often required.
Ewing sarcoma usually presents in the second decade of life with fever, weight loss, bone tenderness, and pathologic fractures. This patient is only 2 years old, and bone marrow aspiration from a patient with Ewing sarcoma would not demonstrate the findings shown in the image.
Multiple myeloma presents in the elderly with renal injury, pathologic fractures, and hypercalcemia. A bone marrow aspirate would show red blood cells (RBCs) in rouleaux formation, stacks of RBCs pushed together by excessive protein, in contrast to this patient’s findings.
Neuroblastoma manifests with constitutional symptoms (fever, weight loss, pallor, hepatosplenomegaly), hypertension, abdominal pain, and an abdominal mass. These symptoms are not consistent with this patient’s presentation.
Wilms tumor manifests as an?
asymptomatic flank mass and/or gross hematuria.
Autoimmune lymphoproliferative syndrome is a rare inherited disorder of apoptosis, which is most commonly due to mutations in the FAS gene. Like HLH, it presents with chronic lymphadenopathy, splenomegaly, and symptomatic cytopenias in an otherwise healthy child. Although specific tests are required to rule out this diagnosis, the ferritin level is typically less than 3000 μg/L, as opposed to the highly elevated ferritin level seen in this patient.
This patient has severe swelling, pain, and redness of the hands and fee; and he has SCD. Dactylitis is a known complication of SCD and occurs because the deformed RBCs block blood circulation. SCD is the result of a?
single nucleotide substitution causing a change from a glutamate (GAG) to a valine (GTG) amino acid on position 6 of the ß-globin gene within DNA.
Codons are three-nucleotide RNA molecules on messenger RNA (mRNA) that code for a particular amino acid. Anticodons are three-nucleotide RNA molecules on transfer RNA (tRNA) that help identify and transfer amino acids to be used in protein translation. Codons and anticodons adhere to the same nucleotide rules that are true for DNA and RNA in general. Adenine pairs with thymine (in DNA) or uracil (in RNA), whereas cytosine pairs with guanine. The codon on the mRNA strand and the anticodon on the tRNA strand are lined up in an antiparallel manner. In this case, we are told that the DNA mutation is 5’-GTG. If we were to translate this to an mRNA codon, it would be?
5’-GUG. Subsequently, the tRNA anticodon for this section of the mRNA would be 5’-CAC.
5’-AGG is incorrect because it does not match up with the anticodon in an antiparallel manner.
5’-CTC and 5’-GTG are incorrect because thymine is not present in RNA.
5’-GUG represents the ?
mRNA sequence for the DNA mutation, not the tRNA anticodon.
This patient is taking heparin and develops thrombocytopenia. The most likely diagnosis is thrombocytopenia secondary to heparin administration. Heparin-induced thrombocytopenia (HIT) is an immunologic reaction to heparin, producing antibodies that cross-react with platelet factor 4, leading to?
platelet activation and clumping.
Ascending paralysis is an unlikely result of HIT as this patient’s antibodies do not cross-react with components of the nervous system.
Rhabdomyolysis, or muscle necrosis, can result from muscle injury such as traumatic compression. However, this patient’s autoantibodies do not cross-react with muscle.
Skin necrosis may result from ?
.warfarin initiation, but does not occur with HIT.
Jaundice can have many causes, including hemolytic anemia and biliary obstruction. While in theory it may occur due to thrombosis of the hepatic vessels, this is a low risk in HIT
This patient’s physical exam demonstrates Courvoisier sign, jaundice and a palpable, enlarged, nontender gallbladder. Courvoisier sign can be found in patients with cancer in the head of the pancreas that is obstructing the distal common bile duct, preventing the gallbladder from emptying. Jaundice is also a sign of biliary obstruction. Patients may also present with significant weight loss and new onset of diabetes mellitus, as the exocrine function of the pancreas becomes compromised.
Approximately 95% of malignant pancreatic neoplasms come from?
exocrine cells. In older patients with sudden insulin insensitivity and a diabetes mellitus diagnosis, pancreatic cancer should be considered. Smoking is the most important environmental risk factor for the development of pancreatic cancer. Treatment usually involves resection of the pancreatic head, duodenum, distal stomach, and gallbladder (Whipple procedure).
Acute hepatitis is unlikely, given the patient’s normal liver function tests. With a palpable mass, cancer is more likely than choledocholithiasis, a stone in the common bile duct. Cholelithiasis refers to stones in the gallbladder, and may present with abdominal pain, nausea, and vomiting, Hemolytic anemia is associated with?
jaundice characterized by a predominantly indirect hyperbilirubinemia, but not an enlarged, palpable mass.
This child presents with signs and symptoms (fever, lethargy, and decreased appetite) that would typically prompt an investigation for infection, starting with a CBC. The white blood cell count in this child is elevated to a degree never seen in an infectious process, so examination of the blood smear is critical.
The blood smear shows a sea of uniform blasts, which is diagnostic of acute leukemia. The blasts have no distinguishing features such as Auer rods (which would be diagnostic of acute myeloblastic leukemia), so a definitive diagnosis of the type of acute leukemia (myeloid or lymphoid) cannot be made. However, in children who present with acute leukemia, the presumptive diagnosis is ?
acute lymphoblastic leukemia . until proven otherwise.
Lymphoblastic leukemia is indicated by greater than 20% leukemic blasts. Patients with acute lymphoblastic leukemia (ALL) often present with?
neutropenia, because the rapid proliferation of WBCs crowds out production of other cells and causes bone marrow failure. They would also present with fatigue, weight loss, night sweats, lymphadenopathy, and anemia.
In acute leukemia of any type, the rapid proliferation of blasts leads to an increase (not a decrease) in serum markers of cell lysis such as lactate dehydrogenase and uric acid. Polycythemia (an increase in red cells) and thrombocytosis (an increase in platelets) are not seen in ?
acute lymphoblastic leukemia. In fact, you see the opposite—anemia and thrombocytopenia—because lymphoblasts crowd out normal hematopoietic precursors in the marrow.
This patient presents with a maculopapular rash, along with a recent history of fever, headaches, malaise, and tick exposure. His blood smear shows berry-like cytoplasmic inclusions in neutrophils, which suggests that the patient contracted?
ehrlichiosis (specifically human monocytic ehrlichiosis).Ehrlichiosis is caused by an obligate intracellular gram-negative species of rickettsiales bacteria, Ehrlichia chaffeensis. As with most rickettsial diseases, it is carried by a tick vector (in this case, the Lone Star tick), with dogs being common vectors. Ehrlichia forms characteristic berry-like cytoplasmic inclusions in macrophages or neutrophils (seen in the image).
Babesiosis is a tick-borne illness that presents with fevers, chills, myalgias, and gastrointestinal symptoms, such as anorexia, nausea, and dark urine. It is known to cause hemolytic anemia, thrombocytopenia, and increased serum creatinine and BUN.
Lyme disease is caused by Borrelia burgdorferi and produces a characteristic target lesion known as erythema chronicum migrans.
Rocky mountain spotted fever, caused by Rickettsia rickettsii, usually causes a characteristic rash that involves the soles and palms.
Typhus fever is caused by ?
members of the genus Rickettsia and is associated with transmission through the feces of fleas and lice. It is usually associated with cramped, unsanitary conditions or exposure to flea-carrying rats.
