Background Studies from different countries have reported an increased incidence of primary cutaneous lymphomas over the last decades.
Objectives To estimate the incidence rates of primary cutaneous T-cell lymphoma (CTCL) and mycosis fungoides (MF)/Sézary syndrome (SS) in Norway, and to compare these rates with those reported from other countries.
Methods Data from the Cancer Registry of Norway on non-Hodgkin lymphomas during the period 1980–2003 were analysed.
Results In total, 337 cases of CTCL were reported to the Cancer Registry during the study period, of which 262 cases were classified as MF/SS. The incidence rate of CTCL increased significantly (Ptrend < 0·001) from 0·16 (95% confidence interval, CI 0·11–0·20) per 100 000 person-years in 1980–84 to 0·29 (95% CI 0·22–0·36) per 100 000 person-years in 2000–2003. The incidence of MF/SS also increased during the same period (Ptrend = 0·05) from 0·15 (95% CI 0·10–0·19) per 100 000 person-years to 0·18 (95% CI 0·13–0·24) per 100 000 person-years.
Conclusions The incidence of both CTCL and MF/SS increased in Norway during the period 1980–2003.