Lymphoma

Definition: primary malignancy of lymphoid tissue.

Classification

Hodgkin's and non-Hodgkin's.
Hodgkin'snon-Hodgkin's
Commonly localisedCommonly generalised
Spread contiguousSpread haematological
Waldeyer's ring rarely involvedWaldeyer's ring commonly involved
Extranodal involvement uncommonExtranodal involvement common

Hodgkin's lymphoma

Definition: Malignant proliferation of Reed-Sternberg cells.

Demographics

Age: peak in 3rd decade, old age.
Sex: M:F 2:1

Features

Lymphadenopathy: usually cervical, axillary.

Mass effect: SVC obstruction, intestinal obstruction.

Systemic: fever, drenching night sweats, weight loss (B symptoms).
Also, pruritis, EtOH induced pain, Pel-Ebstein fever (fever at 15–28/7 intervals).

Histological types

FrequencyPrognosisDescription
Nodular sclerosing20–50%GoodNodular appearance: bands of collagen.
Mixed cellularity20–40%GoodInfiltrate prominent granulocytes, plentiful Reed-Sternberg cells.
Lymphocyte predominant10–15%GoodInfiltrate mostly small lymphocytes.
Lymphocyte depleted1–2%PoorLarge numbers of atypical mononuclear cells.

Staging

Ann Arbor staging A or B. B=fever, weight loss, night sweats.
Stage ISingle lymph node region
Stage IITwo or more lymph node regions on same side of diaphragm
Stage IIILymph nodes on both sides of diaphragm
Stage IVExtranodal involvement
By CT or MRI.

Treatment

IA, IIA—radiotherapy. Chaemotherapy for everyone else. Cure is a realistic goal.

Hodgkin's lymphoma

70–80% 5 y survival.

Non-Hodgkin's lymphomas

B-cell lymphomas are more common than T-cell lymphomas.

Demographics

Peak 7th decade.

B-cell lymphoma

Definition: At least one of CD19, 20, 22. All show immunoglobulin gene re-arrangement.
Divided into low grade (e.g., follicular lymphoma) and high grade (e.g., large cell, Burkitt's lymphoma).

Burkitt's lymphoma

Common among children in equatorial belt of Africa. Characteristic jaw tumour. EBV and malaria? Cohesive medium-sized blasts, 'starry sky' appearance. t[8;14] characteristic.

T-cell lymphoma

Definition: at least one of CD2, 3, 4, 7, 8. All show T-cell receptor rearrangement.
Divided in low grade (e.g., mycosis fungoides) and high grade.

Cutaneous T-cell lymphoma

Helper T-cell phenotype. Lutzner 'cerebriform' cells. Mycosis fungoides when confined to the skin. Sézary syndrome when systemic.