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The correct answer is E. You answered A.

Explanation:

The answer is E.(Chap. 134) Non-Hodgkin lymphoma is the most common lymphoid malignancy (Figure III-67).

 

FIGURE III-67 ALL, acute lymphoid leukemia; CLL, chronic lymphoid leukemia; MALT, mucosa-associated lymphoid tissue.

 

Chronic lymphoid leukemia (CLL) is the most prevalent form of leukemia in Western countries. It occurs most frequently in older adults and is exceedingly rare in children. In contrast to CLL, acute lymphoid leukemias (ALLs) are predominantly cancers of children and young adults. The Burkitt leukemia occurring in children in developing countries seems to be associated with infection by the Epstein-Barr virus (EBV) in infancy. The etiology of ALL in adults is also uncertain. ALL is unusual in middle-aged adults but increases in incidence in the elderly. However, acute myelogenous leukemia (AML) is still much more common in older patients. The preponderance of evidence suggests that Hodgkin lymphoma is of B-cell origin. The incidence of Hodgkin lymphoma appears fairly stable, with 9190 new cases diagnosed in 2014 in the United States. Hodgkin lymphoma is more common in whites than in blacks and more common in males than in females. A bimodal distribution of age at diagnosis has been observed, with one peak incidence occurring in patients in their 20s and the other in those in their 80s. Patients in the younger age groups diagnosed in the United States largely have the nodular sclerosing subtype of Hodgkin lymphoma. Elderly patients, patients infected with HIV, and patients in third-world countries more commonly have mixed-cellularity Hodgkin lymphoma or lymphocyte-depleted Hodgkin lymphoma. Non-Hodgkin lymphomas are more frequent in the elderly and more frequent in men. Patients with both primary and secondary immunodeficiency states are predisposed to developing non-Hodgkin lymphomas. These include patients with HIV infection; patients who have undergone organ transplantation; and patients with inherited immune deficiencies, the sicca syndrome, and rheumatoid arthritis. The incidence of non-Hodgkin lymphomas and the patterns of expression of the various subtypes differ geographically. T-cell lymphomas are more common in Asia than in Western countries, whereas certain subtypes of B-cell lymphomas, such as follicular lymphoma, are more common in Western countries. A specific subtype of non-Hodgkin lymphoma, known as the angiocentric nasal T/natural killer (NK) cell lymphoma, has a striking geographic occurrence, being most frequent in southern Asia and parts of Latin America. A number of environmental factors have been implicated in the occurrence of non-Hodgkin lymphoma, including infectious agents, chemical exposures, and medical treatments. Several studies have demonstrated an association between exposure to agricultural chemicals and an increased incidence of non-Hodgkin lymphoma. Patients treated for Hodgkin lymphoma can develop non-Hodgkin lymphoma; it is unclear whether this is a consequence of the Hodgkin lymphoma or its treatment.