Good but Variable Humoral Response to Trivalent Influenza Vaccination in Patients with Non-Hodgkin’s Lymphoma - Two Seasons Experience.

We assessed humoral response to influenza vaccination (vacc) in two consecutive seasons 2003/2004 and 2004/2005 in 123 NHL patients. In season 03/04 50 patients (29 previously treated with chemotherapy - group A03/04 and 21 not treated - group B03/04) and 73 patients in season 04/05: 34 treated - A04/05, 39 not treated - B04/05 were vaccinated with trivalent subunit influenza vaccine. Antibody responses to influenza hemagglutinin (HI) and neuraminidase (NI) were determined in sera collected before vacc, after 1 month and after 6 months. One month after vacc geometric mean antibody titers (GMTs) of antiHI antibodies significantly increased (p<0.05) and mean fold increases (MFIs) ranged from 10.4 to 24.3 in A03/04, 10.9–11.7 in A04/05, 6.5–31.6 in B03/04 and 14.8–21 in B04/05, than fell after 6 months to 3.6–7.8 in A03/04, 3.7–4.4 in A04/05, 1.7–11.2 in B03/04 and 7.8–8.5 in B04/05. Prevacc protection rate, i.e. the number of subjects with the protective HI antibody titers >1:40, ranged from 3.4 to 10.3% in A03/04, 2.9-8.8% in A04/05, 0–4.6% in B03/04 and 0–5.1% in B04/05. After 1 month protection rates ranged from 78.1 to 87.5% in A03/04, 61.8–70.6% in A04/05, 73.3–93.3% in B03/04 and 66.7–74.4% in B04/05 and decreased after 6 months to 24.1–37.9% in A03/04, 32.4–35.3% in A04/05, 19–47.6% in B03/04 and 17.9–35.9% in B04/05. Response rates, i.e. the number of subjects with at least a 4-fold increase of antiHI antibody titers after vacc, ranged from 58.6–75.9% in A03/04, 50–67.6% in A04/05, 57.1–81% in B03/04 and 61.5–71.8% in B04/05. Six months after vacc it decreased to 17.2–34.5% in A03/04, 20.6–29.4% in A04/05, 19–38.1% in B03/04 and 15.4–33.3% in B04/05. In all patients’ groups, post-vacc antiNI GMTs were significantly higher (p<0.05) than pre-vacc. MFIs of antiNI antibodies 1 month after vacc ranged from 11 to 17.5 in A03/04, 4.1–9.4 in A04/05, 5.1–9.9 in B03/04 and 6.3–9.9 in B04/05, then fell to 2.9–6.9 in A03/04, 1.3–5.1 in A04/05, 3.4–4.9 in B03/04 and 2.8–3.6 in B04/05. In season 03/04 only hemagglutinin H1 antibody titers were significantly higher in CTR than in patients in contrast of season 04/05 when in patients the titers of H1, H3 and N1, N2, NB were significantly lower. We conclude that the response to influenza vaccine is similar in patients previously treated and not-treated with chemoterapy. It is highly immunogenic in NHL patients, but the level of specific antibodies is variable and may depend on immunogenecity of vaccine for actual season. After 6 months the antibody titers rapidly decline, thus the NHL patients may need the second dose of vaccine to maintain good protective level.