Table 1. General characteristics of all Hodgkin lymphoma patients and colorectal cancer (CRC) patients.

	Cohort	%	CRC cases	%
All patients	3121	100.0	55	100.0
Sex
Men	1776	56.9	34	61.8
Women	1345	43.1	21	38.2
Age at first HL treatment (years)
Median (IQR)	27.3 (21.0–35.5)		30.4 (23.4–41.8)
<25a	1284	41.2	17	30.9
25–34	1009	32.3	16	29.1
35–50	828	26.5	22	40.0
Stage HL
I	719	23.0	12	21.8
II	1398	44.8	15	27.3
III & IV	795	25.5	16	29.1
Unknown	209	6.7	12	21.8
Treatment period
1965–1974	660	21.1	25	45.5
1975–1984	1045	33.5	23	41.8
1985–1995	1416	45.4	7	12.7
Follow-up (years)
Median (IQR)	22.9 (16.7–30.7)		22.9 (16.7–30.7)
5–9	304	9.8	2	3.6
10–19	869	27.8	16	29.1
20–29	1218	39.0	21	38.2
⩾30	730	23.4	16	29.1
Treatment for HL
Treatment categoryb
CT only	318	10.2	3	5.5
Supradiaphragmatic RT, no CT	342	11.0	3	5.5
Supradiaphragmatic RT+CT	983	31.5	13	23.6
Infra-±supradiaphragmatic RT, no CT	599	19.2	9	16.3
Infra-±supradiaphragmatic RT+CT	879	28.1	27	49.1
Infradiaphragmatic irradiationb
No infradiaphragmatic RTc	1643	52.6	19	34.6
PAO	321	10.3	6	10.9
PAO+spleen	619	19.8	8	14.6
Inverted Yd±spleen	423	13.6	18	32.7
Infradiaphragmatic othere	115	3.7	4	7.2
CT regimenb
No CT	940	30.1	12	21.8
MOPP or MOPP-likef	914	29.3	28	50.9
MOPP and ABVD	152	4.9	2	3.6
MOPP and ABV	577	18.5	4	7.3
EBVP	61	1.9	0	0
ABVD	101	3.2	0	0
Otherg	376	12.1	9	16.4
CT treatment according to cumulative procarbazine doseh,b
No CT	940	30.1	12	21.8
Non-alkylating CT only	147	4.7	3	5.5
Alkylating CT, no procarbazine	169	5.4	1	1.8
Alkylating CT, ≤4.2 g m−2 procarbazine	577	18.5	5	9.1
Alkylating CT, >4.2–8.4 g m−2 procarbazine	684	21.9	17	30.9
Alkylating CT, >8.4 g m−2 procarbazine	433	13.9	14	25.4
CT, type unknown	171	5.5	3	5.5
Age at CRC diagnosis (years)
Median (IQR)	—	—	56.4 (50.6–62.2)

Abbreviations: ABVD=doxorubicin, bleomycin, vinblastine, dacarbazine; CRC=colorectal cancer; CT=chemotherapy; EBVP=epirubicine, bleomycin, vinblastine, prednisone; HL=Hodgkin lymphoma; MOPP=mechlorethamine, vincristine, procarbazine, prednisone; MOPP-ABV(D)= mechlorethamine, vincristine, procarbazine, prednisone – doxorubicin, bleomycin, vinblastine, (dacarbazine); PAO=para-aortic; IQR=inter quartile range; RT=radiation therapy.

^aIn all, 218 patients (7.0%) were younger than 15 years at HL diagnosis.

^bIncluded primary and relapse therapy. RT includes all radiation fields.

^cNo RT or supradiaphragmatic RT only.

^dInverted Y field consists of para-aortic and iliac nodes.

^eInclude iliacal and inguinal fields.

^fMOPP-like regimens include at least procarbazine, e.g. CVPP-LO, COPP, CHOPP, MVPP, LOPP.

^gIncludes single agents, other CT regimens, and CT agent unknown.

^hMutually exclusive categories.