Progressive transformation of germinal centers is a condition in which a lymph node becomes very enlarged (lymphadenopathy). Typically, only one lymph node is affected, though PTGC can involve multiple lymph nodes. The neck is the most common location of affected lymph nodes, but PTGC may also affect lymph nodes in the groin and armpits. Adults are more frequently affected than children, but children have a higher chance of developing PTGC multiple times (recurrence). PTGC is not considered a precancerous condition, though it has been associated with Hodgkin lymphoma.

The cause of progressive transformation of germinal centers (PTGC) is currently unknown. Also, there is no evidence in the medical literature that PTGC is a genetic condition.

Because progressive transformation of germinal centers (PTGC) is considered a benign condition and usually has no symptoms other than the enlarged lymph node, no treatment is necessary. The enlarged lymph node may stay the same size or shrink over time. Affected individuals should have regular follow-up visits with their physician; a biopsy should be taken of any new enlarged lymph node because PTGC is associated with Hodgkin lymphoma in some individuals.