A better understanding of the biology and pathogenesis of
hematological malignancies has led to the development of immunotherapeutic and immunoregulatory drugs. Many of these agents have revolutionized the current treatment modalities, while others are under investigation.
Rituximab (anti-CD20 antibody) has been established as the gold standard of treatment for aggressive
B-cell lymphomas in combination with CHOP and has shown significant activity as monotherapy in the treatment of indolent
B-cell lymphomas. In
follicular lymphomas the combination of
Rituximab with
chemotherapy improves the outcome compared to
chemotherapy alone. CD 20-based
radioimmunotherapy, with the advantage of the bystander effect, represents an additional therapeutic alternative in
B-cell lymphomas and may produce
tumor regression in
Rituximab resistant patients. The anti-CD52
monoclonal antibody,
alemtuzumab, further expands the armamentarium against lymphoid
malignancies producing high response rates in these entities. Antibody-targeted
chemotherapy such as
gemtuzumab ozogamicin, consisting of an anti-CD33 antibody combined to
calicheamicin, has shown efficacy in the treatment of refractory
acute myeloid leukemia; exact indications, timing and dosing schedule for optimized efficacy remain to be determined.
Interferons have proven significant activity in cutaneous
lymphomas,
hairy cell leukemia and
chronic myelogenous leukemia by mechanisms that are not fully elucidated.
Thalidomide, by acting as an immunomodulatory and
antiangiogenic agent can modulate neoplastic cells microenvironment and lead to disease control in
multiple myeloma as well as in numerous other
hematological malignancies.
Bortezomib, a
proteasome inhibitor, displays significant anti-
tumor activity, especially in
multiple myeloma and
lymphoproliferative disorders. The addition of these agents in therapeutic regimens has improved considerably the treatment of
hematological malignancies.