The age-adjusted incidence of carcinoid tumors worldwide is approximately 2 per 100,000 persons.[1,2] The average age at diagnosis is 61.4 years. Carcinoid tumors represent about 0.5% of all newly diagnosed malignancies.[2,3]
Carcinoid tumors are rare, slow-growing tumors that originate in cells of the diffuse neuroendocrine system. They occur most frequently in tissues derived from the embryonic gut. Foregut tumors, which account for up to 25% of cases, arise...
The goal of the first phase of therapy (remission induction) is to induce a complete remission (CR). This phase typically lasts 4 weeks. Overall, approximately 98% of patients with newly diagnosed B-precursor ALL achieve CR by the end of this phase, with somewhat lower rates in patients with T-cell ALL or high presenting leukocyte counts.[1,2,3,4,5]
Induction chemotherapy consists of the following drugs, with or without an anthracycline:
The most common four-drug induction regimen is vincristine, corticosteroid (either dexamethasone or prednisone), L-asparaginase, and either doxorubicin or daunorubicin. In a randomized trial of doxorubicin and daunorubicin during induction, there were no differences between these two agents in early response measures, including reduction in peripheral blood blast counts during the first week of therapy, day 15 marrow morphology, and end-induction minimal residual disease (MRD) levels.[Level of evidence: 1iiDiv] Some studies have suggested that this more intensive induction regimen may result in improved event-free survival (EFS) in patients presenting with high-risk features, but it may not be necessary for favorable outcome provided that adequate postremission intensification therapy is administered.[7,8] The COG reserves the use of a four-drug induction for patients with high-risk B-precursor ALL and T-cell ALL.
Many current regimens utilize dexamethasone instead of prednisone during remission induction and later phases of therapy.
The Children's Cancer Group conducted a randomized trial that compared dexamethasone and prednisone in standard-risk ALL patients.
The trial reported that dexamethasone was associated with a superior EFS.
Another randomized trial was conducted by the United Kingdom Medical Research Council.
The trial demonstrated that dexamethasone was associated with a more favorable outcome than prednisolone in all patient subgroups.
Patients who received dexamethasone had a significantly lower incidence of both central nervous system (CNS) and non-CNS relapses than patients who received prednisolone.
Other randomized trials did not confirm an EFS advantage with dexamethasone.[11,12]