Skip to content

Core Outcome Set for CApillary Malformations (COSCAM)


Capillary malformations (a.k.a. port wine stains)


Capillary malformations (a.k.a. port wine stains; PWSs) are red to purple lesions affecting the dermis and are usually present at birth. These congenital lesions have been associated with somatic mosaic mutations in the GNA (Q or 11) gene. They occur in about 1% of newborns and frequently appear as flat, pink macules that gradua evolve into more hypertrophic, red-to purple lesions. About two-thirds of the patients develop nodular or papular elements as a result of soft tissue overgrowth, leading to asymmetry, dysmorphia, and possibly sporadic spontaneous bleeding. Most of these lesions are located in the head and neck and have shown to seriously affect the quality of life of these patients, ranging from impaired emotional quality of life to functional problems. This is therefore an important reason to treat PWSs. Yet, the effectiveness of current therapies is still far from optimal.

Due to a large variety in treatment outcomes reported, a lack of outcomes relevant to patients, and a large heterogeneity in outcome measures used, it is hard to adequately compare and improve current treatment regimens for patients with PWSs. The Core Outcome Set for CApillary Malformations (COSCAM) project aims to reach international consensus on a core outcome set (COS) for clinical research on capillary malformations, hereby unifying outcome reporting for this difficult-to-treat and disfiguring skin condition.

Scope of the intended COS

  • Study types: all clinical research
  • Region: global scope


Development of a core outcome set, comprised of a core domain set and a core outcome measurement set. For the core domain set a systematic review on outcome domains was already performed. We will execute an e-Delphi study to reach international consensus on the core domain set. For the core outcome measurement set: a systematic review on outcome measurement instruments, evaluation of existing outcome measurement instruments, development of disease-specific questionnaire for the patient-reported outcome domains for which instruments are lacking.

Involvement of stakeholders

International PWS patients, caregivers, researchers, clinicians, PWS experts

Current status

Finalizing protocol for e-Delphi study and start with patient recruitment.


no funding

Involved Countries

The Netherlands, Switzerland, Hungary, Sweden, Denmark, USA, Australia (so far, more to participate).

Date of updates



Ginger Beau Langbroek

Project team members

  • Dr. Hans-Joachim Laubach
  • Dr. Ashraf Badawi
  • Dr. Kristen Kelly
  • Dr. Agneta Troilius
  • Dr. Merete Haedersdal
  • Dr. Taro Kono
  • Pablo Boixeda
  • Woraphong Manuskiatti
  • Ingmar van Raath
  • Susan Robertson
  • FirasĀ al-Niaimi
  • Dirk Ubbink
  • Chantal van der Horst
  • Albert Wolkerstorfer
  • Sophie Horbach
  • Phyllis Spuls

Responsible member of Methods group (as assigned by CS-COUSIN)

  • Phyllis Spuls



Published references

  1. van Raath MI, Chohan S, Wolkerstorfer A, van der Horst CMAM, Limpens J, Huang X, Ding B, Storm G, van der Hulst RRWJ, Heger M. Clinical outcome measures and scoring systems used in prospective studies of port wine stains: A systematic review. PLoS One. 2020;15(7):e0235657-e0235657. doi:10.1371/journal.pone.0235657