European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 1: treatment delivery and established indications – actinic keratoses, Bowen''s disease and basal cell carcinomas

Topical photodynamic therapy (PDT) is a widely approved therapy for actinic keratoses, Bowen''s disease (squamous cell carcinoma in situ), superficial and certain thin basal cell carcinomas. Recurrence rates when standard treatment protocols are used are typically equivalent to existing therapies, although inferior to surgery for nodular basal cell carcinoma. PDT can be used both as lesional and field therapies and has the potential to delay/reduce the development of new lesions. A protocol using daylight to treat actinic keratoses is widely practised, with conventional PDT using a red light after typically a 3-h period of occlusion employed for other superficial skin cancer indications as well as for actinic keratoses when daylight therapy is not feasible. PDT is a well-tolerated therapy although discomfort associated with conventional protocol may require pain-reduction measures. PDT using daylight is associated with no or minimal pain and preferred by patient. There is an emerging literature on enhancing conventional PDT protocols or combined PDT with another treatment to increase response rates. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical PDT in dermatology, prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence

Diagnosis of acute promyelocytic leukaemia by RT-PCR: detection of PML-RARA and RARA-PML fusion transcripts

Acute promyelocytic leukaemia (APL; AML M3) is identified by a unique t(15;17) translocation which fuses the PML gene to the retinoic acid receptor alpha gene (RARA). Reverse transcription coupled with the polymerase chain reaction (RT-PCR) has been used to develop a diagnostic test for APL based on the PML-RARA fusion message. Separate PCR assays were designed to amplify either PML-RARA (15q+ derived) or RARA-PML (17q- derived) chimaeric transcripts. PML-RARA transcripts were detected in every case from a series of 18 APL patients with cytogenetically confirmed t(15;17) translocations, whereas RARA-PML messages were detected in only 67% (12/18) of these patients. This suggests that it is the 15q+ derivative which mediates leukaemogenesis. Furthermore the PCR approach (or Southern analysis) may be used to identify in which of the alternative PML introns the breakpoint occurs; 52% of cases (15/29 patients) utilize a 5' PML intron and 48% the 3' intron (14/29 cases). Neither the choice of PML intron nor the expression of the 17q- derivative could be correlated with the microgranular variant of APL (M3V), overall survival rate, age, sex or presence of coagulopathy. Finally, the fusion message is undetectable in five remission samples. This indicates a possible use for RT-PCR in monitoring remission patients for evidence of relapse