Journal of Clinical Apheresis 6:216-220 (1991)
Photopheresis in the 1990s lnger Christensen and Peter Heald Photophoresis Service, Yale University School of Medicine, New Haven, Connecticut Key words: photochemotherapy, leukapheresis, 8 methoxypsoralen, 8MOP
EXTRACORPOREAL PHOTOCHEMOTHERAPY (PHOTOPHERESIS)
Photochemotherapy and leukapheresis are combined in a new treatment procedure termed photopheresis [ 1,2]. In this therapy patients ingest 8 methoxypsoralen (8MOP) and 1-2 hours later they have an indwelling catheter placed to perform a leukapheresis. Most of the red blood cells and plasma are returned to the patient while 240 cc of buffy cost is collected and diluted with approximately 200 cc plasma and 300 cc saline. The fraction of the circulating lymphocyte pool which is harvested is approximately 10-15%. That figure is based on circulating lymphocytes (31. A cutaneous T-cell lymphoma CTCL patient has considerable extravascular (primary cutaneous) compartmentalization of lymphocytes which would put the total fraction of lymphocytes treated at less than 5%. From the start of buffy coat collection the cells are pumped through a disposable clear plastic plate which rests between two banks of ultraviolet A emitting bulbs. The separation and irradiation phases are both carried out by a bedside treatment unit (Fig. 1). The irradiation with the low energy light activates the 8MOP to become an alkylating agent that reverts to its inactive state upon leaving the irradiation chamber. The irradiation phase continues for up to 1-2 hours following completion of leukapheresis. Reinfusion of the treated cells is the last phase of the treatment making the total treatment time fall in the range of 3-4 hours. Patients undergo two treatments on consecutive days every 4 weeks. This strategy has been found to therapeutically be effective with minimal side effects [2]. Initially, it is important to establish a therapeutic level of 8MOP. Since the treatment involves generating a suspension of buffy coat, heparin, saline, and plasma, it is best to check the 8MOP level here rather than in the blood. The liquid 8MOP (Ultra) is administered initially at 10 mg over the recommended dose for PUVA which is close to .5 mg/kg. A treatment is then initiated 75-90 minutes after ingestion of the drug. A treatment bag level of greater than 60 nglml is therapeutic. If the initial dose is well tolerated and >lo0 ng/ml is in the treatment bag then this dose is utilized. Nausea and other subjective
0 1991 Wiley-Liss, Inc.
signs may dictate a move to a lower dose so long as the bag level is again checked and is >60 ng/ml [4]. Once the proper dose is established the other routine laboratory values routinely checked are complete blood counts pretreatment and from the leukapheresis sample. The hematocrit of the latter should be
Photopheresis in the 1990s lnger Christensen and Peter Heald Photophoresis Service, Yale University School of Medicine, New Haven, Connecticut Key words: photochemotherapy, leukapheresis, 8 methoxypsoralen, 8MOP
EXTRACORPOREAL PHOTOCHEMOTHERAPY (PHOTOPHERESIS)
Photochemotherapy and leukapheresis are combined in a new treatment procedure termed photopheresis [ 1,2]. In this therapy patients ingest 8 methoxypsoralen (8MOP) and 1-2 hours later they have an indwelling catheter placed to perform a leukapheresis. Most of the red blood cells and plasma are returned to the patient while 240 cc of buffy cost is collected and diluted with approximately 200 cc plasma and 300 cc saline. The fraction of the circulating lymphocyte pool which is harvested is approximately 10-15%. That figure is based on circulating lymphocytes (31. A cutaneous T-cell lymphoma CTCL patient has considerable extravascular (primary cutaneous) compartmentalization of lymphocytes which would put the total fraction of lymphocytes treated at less than 5%. From the start of buffy coat collection the cells are pumped through a disposable clear plastic plate which rests between two banks of ultraviolet A emitting bulbs. The separation and irradiation phases are both carried out by a bedside treatment unit (Fig. 1). The irradiation with the low energy light activates the 8MOP to become an alkylating agent that reverts to its inactive state upon leaving the irradiation chamber. The irradiation phase continues for up to 1-2 hours following completion of leukapheresis. Reinfusion of the treated cells is the last phase of the treatment making the total treatment time fall in the range of 3-4 hours. Patients undergo two treatments on consecutive days every 4 weeks. This strategy has been found to therapeutically be effective with minimal side effects [2]. Initially, it is important to establish a therapeutic level of 8MOP. Since the treatment involves generating a suspension of buffy coat, heparin, saline, and plasma, it is best to check the 8MOP level here rather than in the blood. The liquid 8MOP (Ultra) is administered initially at 10 mg over the recommended dose for PUVA which is close to .5 mg/kg. A treatment is then initiated 75-90 minutes after ingestion of the drug. A treatment bag level of greater than 60 nglml is therapeutic. If the initial dose is well tolerated and >lo0 ng/ml is in the treatment bag then this dose is utilized. Nausea and other subjective
0 1991 Wiley-Liss, Inc.
signs may dictate a move to a lower dose so long as the bag level is again checked and is >60 ng/ml [4]. Once the proper dose is established the other routine laboratory values routinely checked are complete blood counts pretreatment and from the leukapheresis sample. The hematocrit of the latter should be
