Table 2.
HL Treatment | Cases (n = 89) |
Controls (n = 190) |
OR | 95% CI | Ptrenda | ||||
---|---|---|---|---|---|---|---|---|---|
No. | % | Mean | No. | % | Mean | ||||
Radiotherapy fieldsb | |||||||||
No radiotherapy | 7 | 8 | 26 | 14 | 1.0 | Referent | |||
Any subdiaphragmatic fields | 61 | 69 | 71 | 37 | 6.2 | 2.1 to 21.4 | |||
Supradiaphragmatic fields only | 20 | 22 | 90 | 47 | 1.4 | 0.5 to 4.5 | |||
Radiation dose, Gyc,d | < .001 | ||||||||
0 | 9 | 10 | 0.0 | 27 | 14 | 0.0 | 1.0 | Referent | |
0.1 to 0.9 | 13 | 15 | 0.3 | 41 | 22 | 0.4 | 1.3 | 0.4 to 4.1 | |
1.0 to 4.9 | 13 | 15 | 2.4 | 50 | 26 | 1.9 | 1.0 | 0.3 to 3.5 | |
5.0 to 24.9e | 4 | 4 | 18.9 | 20 | 11 | 15.8 | 0.5 | 0.1 to 2.7 | |
25.0 to 34.9 | 12 | 13 | 30.4 | 11 | 6 | 31.6 | 4.6 | 1.2 to 20.5 | |
35.0 to 39.9 | 24 | 27 | 37.9 | 16 | 8 | 37.9 | 8.2 | 2.6 to 29.7 | |
≥ 40 | 12 | 13 | 43.3 | 16 | 8 | 42.6 | 4.2 | 1.2 to 15.6 | |
AA chemotherapy, No. of cyclesf | .02 | ||||||||
0 | 33 | 37 | 0.0 | 88 | 46 | 0.0 | 1.0 | Referent | |
1 to 5 | 16 | 18 | 3.4 | 35 | 18 | 2.6 | 1.0 | 0.5 to 2.4 | |
6 | 15 | 17 | 6.0 | 29 | 15 | 6.0 | 1.7 | 0.7 to 4.4 | |
7 to 10 | 10 | 11 | 8.2 | 22 | 12 | 8.4 | 1.9 | 0.7 to 4.9 | |
≥ 11 | 15 | 17 | 19.1 | 16 | 8 | 21.1 | 3.0 | 1.2 to 7.7 | |
Analyses of specific AAs, mg/m2g | |||||||||
Procarbazine | 52 | 58 | 8,752.0 | 87 | 46 | 6,528.3 | 1.9 | 1.1 to 3.5 | .003 |
Nitrogen mustard | 39 | 44 | 62.3 | 77 | 41 | 50.5 | 1.2 | 0.7 to 2.2 | .06 |
Cyclophosphamide | 10 | 11 | 9,249.5 | 27 | 14 | 7,533.3 | 1.0 | 0.4 to 2.3 | .70 |
Dacarbazine | 12 | 13 | 2,180.8 | 9 | 5 | 2,295.6 | 9.3 | 2.5 to 45.8 | .008 |
Lomustine | 5 | 6 | 548.6 | 9 | 5 | 333.0 | 2.3 | 0.7 to 7.9 | .12 |
Chlorambucil | 7 | 8 | 452.6 | 4 | 2 | 1,357.6 | 3.4 | 0.9 to 14.6 | .59 |
Multivariate modelh | |||||||||
Radiation dose, Gyc | < .001 | ||||||||
< 25 | 39 | 44 | 2.8 | 138 | 73 | 3.1 | 1.0 | Referent | |
≥ 25 | 48 | 54 | 37.4 | 43 | 23 | 38.0 | 5.8 | 3.0 to 12.3 | |
Procarbazine dose, mg/m2i | .009 | ||||||||
0 | 37 | 42 | 0.0 | 103 | 54 | 0.0 | 1.0 | Referent | |
1 to 5,599 | 12 | 13 | 3,011.8 | 39 | 21 | 3,403.0 | 0.8 | 0.3 to 1.9 | |
5,600 to 8,399 | 22 | 25 | 6,775.3 | 29 | 15 | 6,938.9 | 2.9 | 1.2 to 7.0 | |
≥ 8,400 | 18 | 20 | 14,994.7 | 19 | 10 | 12,316.5 | 2.3 | 1.0 to 5.5 | |
Dacarbazine dose, mg/m2 | .04 | ||||||||
0 | 77 | 87 | 0.0 | 181 | 95 | 0.0 | 1.0 | Referent | |
> 0 | 12 | 13 | 2,180.8 | 9 | 5 | 2,295.6 | 8.8 | 2.1 to 46.6 |
Abbreviations: AA, alkylating agent; ABV, doxorubicin, bleomycin, vinblastine; BEACOPP, bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone; HL, Hodgkin lymphoma; MOPP, nitrogen mustard (mechlorethamine), vincristine, procarbazine, prednisone; OR, odds ratio.
Ptrend in dose was calculated using continuous variables on linear scale for irradiation or log-linear scale for AA chemotherapy.
Details on radiotherapy fields are provided in Figure 1. One case (1%) and three controls (2%) received radiotherapy but did not have detailed information on field type. ORs and 95% CIs were adjusted for No. of cycles of AA-containing regimens.
Radiation dose was estimated to specific site of stomach tumor (matched location for controls).
ORs and 95% CIs were adjusted for No. of cycles of AA-containing chemotherapy. Patients with unknown radiation dose (two cases, nine controls with insufficient details on radiotherapy) were modeled separately with indicator variable and excluded from percentages.
Includes patients with 5.0 to 9.9 (zero cases, five controls), 10.0 to 14.9 (one case, four controls), 15.0 to 19.9 (one case, five controls), and 20.0 to 24.9 Gy (two cases, six controls).
Includes both cyclic and continuous chemotherapy, with 1 month of continuous therapy counted as one cycle. OR (95% CI) was adjusted for radiation dose (unknown; < 25, ≥ 25 Gy).
Each AA was modeled separately with adjustment for radiation dose (unknown; < 25, ≥ 25 Gy). ORs and 95% CIs compare patients who received that AA with referent group of patients who did not. Ptrend uses cumulative dose (mg/m2).
Multivariate model included radiation, procarbazine, and dacarbazine and was also adjusted for unknown radiation dose (two cases, nine controls).
Assuming procarbazine dose of 1,400 mg/m2 per cycle (14 days × 100 mg/m2 per day), categories correspond to zero, one to three, four to five, and ≥ six cycles of MOPP or MOPP-like regimens. Other protocols (eg, MOPP-ABV, BEACOPP) include procarbazine dose of 700 mg/m2 per cycle.