Table 3.
Risk of Melanoma After First Primary NHL, by Subtype, in Relation to NHL Treatments
| NHL Treatment | Total NHL |
Melanoma Cases |
||||
|---|---|---|---|---|---|---|
| No. | % | No. | % | HR* | 95% CI | |
| Patients diagnosed with first primary CLL/SLL | ||||||
| Infused chemotherapy | ||||||
| None recorded | 8,899 | 63.8 | 52 | 57.1 | 1.00 | Referent |
| Model A† | ||||||
| Any rituximab | 3,744 | 26.8 | 27 | 29.7 | 1.43 | 0.77 to 2.67 |
| Any fludarabine | 2,958 | 21.2 | 28 | 30.8 | 1.90 | 1.08 to 3.37 |
| Any cyclophosphamide | 2,402 | 17.2 | 19 | 20.9 | 1.11 | 0.59 to 2.08 |
| Model B‡ | ||||||
| Fludarabine without rituximab | 917 | 6.6 | 10 | 11.0 | 2.92 | 1.42 to 6.01 |
| Rituximab without fludarabine | 1,703 | 12.2 | < 10 | — | 1.63 | 0.79 to 3.38 |
| Fludarabine + rituximab | 2,041 | 14.6 | 18 | 19.8 | 1.92 | 1.09 to 3.40 |
| Radiotherapy | ||||||
| No | 12,925 | 92.7 | 85 | 93.6 | 1.00 | Referent |
| Yes | 1,025 | 7.3 | < 10 | — | 0.86 | 0.31 to 2.40 |
| Patients diagnosed with first primary NHL other than CLL/SLL | ||||||
| Infused chemotherapy | ||||||
| None recorded | 10,040 | 32.5 | 34 | 30.6 | 1.00 | Referent |
| Model A† | ||||||
| Any rituximab | 15,726 | 50.9 | 53 | 47.8 | 1.06 | 0.62 to 1.84 |
| Any fludarabine | 2,518 | 8.1 | < 10 | — | 1.22 | 0.57 to 2.61 |
| Any cyclophosphamide | 16,786 | 54.3 | 68 | 61.3 | 1.44 | 0.89 to 2.35 |
| Model B‡ | ||||||
| Cyclophosphamide without rituximab | 4781 | 15.5 | 24 | 21.6 | 1.78 | 0.97 to 3.25 |
| Rituximab without cyclophosphamide | 3,721 | 12.0 | < 10 | — | 0.99 | 0.45 to 2.19 |
| Cyclophosphamide + rituximab | 12,005 | 38.8 | 44 | 39.6 | 1.27 | 0.77 to 2.12 |
| Radiotherapy | ||||||
| No | 21,051 | 68.1 | 76 | 68.5 | 1.00 | Referent |
| Yes | 9,869 | 31.9 | 35 | 31.5 | 1.11 | 0.73 to 1.69 |
NOTE. Treatments received by fewer than 10 melanoma cases are not reported here but are included in Appendix Table 1 (eg, other alkylating agents, epipodophyllotoxins, and hematopoietic stem cell transplantation). Counts and percentages are not reported for fewer than 10 melanoma cases to protect patient confidentiality.
Abbreviations: CLL/SLL, chronic lymphocytic leukemia/small lymphocytic lymphoma; HR, hazard ratio; NHL, non-Hodgkin lymphoma.
HR (95% CI) adjusted for sex, race, residence, Charlson comorbidity index, socioeconomic status, and follow-up time (time-dependent covariate) and stratified by calendar year. Age was used as the time scale. Time-dependent covariates were used to indicate receipt of any radiotherapy or chemotherapy during follow-up on the basis of timing of initiation of therapy. Model A represents risk for patients who received any of the three main chemotherapy agents with separate indicator variables for each agent. The categories in model B are mutually exclusive. The HRs for chemotherapy in models A and B were additionally adjusted for receipt of other alkylating agents. The HR for radiotherapy was additionally adjusted for chemotherapy using model B.
Percentages do not add up to 100% because groups are not mutually exclusive.
Percentages do not add up to 100% because a small number of patients received other agents.