Non-Hodgkin Lymphoma

SOURCE

Source: Chan A, Sessions J. Lymphomas. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. http://accesspharmacy.mhmedical.com/content.aspx?bookid=1861&sectionid=133894009. Accessed April 13, 2017.

DEFINITION

• Heterogeneous group of lymphoproliferative disorders.

ETIOLOGY

• Unknown.

PATHOPHYSIOLOGY

• Derived from monoclonal proliferation of malignant B or, less commonly, T lymphocytes and their precursors.

• Current classification schemes characterize Non-Hodgkin lymphomas (NHLs) according to cell of origin, clinical features, and morphologic features.

• World Health Organization (WHO) classification terms:

  • Grade refers to histologic parameters such as:

    • Cell and nuclear size.

    • Density of chromatin.

    • Proliferation fraction.

  • Aggressiveness denotes clinical behavior of a tumor.

EPIDEMIOLOGY

• Fifth most common cause of newly diagnosed cancer in the United States.

• Average age at diagnosis: 67 years.

RISK FACTORS

• Certain infections associated with development of lymphoma:

  • EBV: Burkitt lymphoma.

  • Kaposi sarcoma-associated herpes virus (KSHV)

  • Human T-cell lymphotropic virus type 1: adult T-cell leukemia/lymphoma.

• Congenital and acquired immunodeficiency states.

• Exposure to herbicides, chemical solvents, and dyes.

CLINICAL PRESENTATION

• Patients present with variety of symptoms, which depend on site of involvement and whether nodal or extranodal.

SIGNS AND SYMPTOMS

• Adenopathy can be localized or generalized.

  • Involved nodes painless, rubbery, and discrete, and usually located in cervical and supraclavicular regions.

• Constitutional (B symptoms) in ~40% of patients.

  • Fever.

  • Drenching night sweats.

  • Weight loss.

• Extranodal disease in 10–35% of patients at diagnosis.

  • Mesenteric or gastrointestinal (GI) involvement:

    • Nausea.

    • Vomiting.

    • Obstruction.

    • Abdominal pain.

    • Palpable abdominal mass.

    • GI bleeding.

  • Bone marrow involvement:

    • Anemia.

    • Neutropenia.

    • Thrombocytopenia.

DIAGNOSIS

MEANS OF CONFIRMATION AND DIAGNOSIS

• Pathologic review of tissue obtained by excisional biopsy of involved lymph node.

LABORATORY TESTS

• Metabolic panel.

• Complete blood count (CBC)

IMAGING

• Chest radiography.

• Computed tomography (CT) of abdomen and pelvis.

DIAGNOSTIC PROCEDURES

• Excisional lymph node biopsy.

• Bone marrow aspiration and biopsy.

STAGING

• Systems for classifying NHLs continue to evolve.

  • Slow-growing or indolent lymphomas have favorable outcomes (untreated survival measured in years).

  • Rapid-growing or aggressive lymphomas have unfavorable outcomes (untreated survival measured in weeks to months).

• International Prognostic Index (IPI) for aggressive lymphomas.

DIFFERENTIAL DIAGNOSIS

• Hodgkin lymphoma

• Infectious mononucleosis.

• Metastatic cancer.

DESIRED OUTCOMES

• Relieve symptoms and, whenever possible, cure patient of disease while minimizing risk of serious toxicity.

TREATMENT: GENERAL APPROACH

• Therapy depends ...