Prognostic Instrument for Melanoma

Prognostic Instrument (2.0) is a population-based tool that is based on a large amount of clinical and histopathological data from the Swedish quality registry for cutaneous melanoma (SweMR).

The prognostic instrument has been designed for use by physicians in relation to patients with primary malignant melanoma.

The analyses that form the basis of the instrument are performed on separate models for thin melanomas (≤ 1mm) and thicker melanomas (> 1mm) due to the fact that sentinel lymph node biopsy (SLNB) is generally not recommended for thin melanomas in Sweden. When choosing a thickness of 1 mm or less in the instrument, "Sentinel lymph node status" will not be included as a parameter.

After selecting the tumor thickness, other parameters are activated that must be filled in.

Select parameters

Tumour thickness
Histopathological subtype
Tumour location
Tumour ulceration
Clark's level of invasion

Clark's level of invasion
Sentinel lymph node status


In this updated version of the instrument, data from more than 70,000 patients with primary malignant melanoma between 1990 and 2021 have been included. Through a combination of several independent risk factors, melanoma-specific survival has been analysed for a variety of risk groups. The instrument calculates survival 1 to 10 years after diagnosis and provides an analysis at group level but can never provide an exact individual prognosis. The results are presented with 95% confidence intervals.

For further reading about how the prognostic instrument is constructed read this article published in European Journal of Surgical Oncology.

  1. The instrument is based on data from the Swedish Melanoma Registry and Swedish residents and may not work reliably in relation to other populations.
  2. The prognostic estimate generated by the instrument must be interpreted in relation to its clinical significance for the patient in question.
  3. The information generated in the instrument may only be used as a general guide.
  4. The Swedish Melanoma Registry and the individuals who contributed to the design of the prognostic instrument make no guarantees or representations to any physician or patient regarding the accuracy, completeness, timeliness or usefulness of any prognostic estimate generated by the instrument; and
  5. The Swedish Melanoma Registry and the individuals who contributed to the design of the instrument will have no liability towards the doctor or any patient for the consequences of any treatment decision made - or any action taken or not taken - by the doctor or his patient after using the prognosis instrument.