Does surgical removal of primary melanoma trigger growth of occult metastases? An analytical epidemiological approach.
BACKGROUND
In several human tumor systems a potential role of surgical removal of the primary tumor upon metastatic tumor growth has been evaluated, as it has been in experimental models. The present study addresses the question of whether the removal of primary melanomas disinhibits growth of metastatic disease and results in more rapid progression.


METHODS
In a data set of 1224 primary cutaneous melanomas the risk of "thin" melanomas to develop metastases within 1 year was compared with the risk of matched pairs of "thick" melanomas to present metastases at the time of diagnosis. For this purpose, a pairwise matching procedure based on certain assumptions as to tumor volume and tumor doubling time has been applied.


RESULTS
When a long tumor doubling time is assumed (200, 400, or 800 days), the tumors removed seem to have a significantly higher risk of metastases to become clinically apparent within 1 year than the matched pairs of tumors to present metastatic disease at the time of diagnosis (chi-square < 0.01). When short tumor doubling time is assumed (50 or 100 days), the difference is not significant, but there also seems to be no benefit for the operated patients.


CONCLUSIONS
In the present data set there is evidence that surgery of primary melanoma may enhance tumor growth at metastatic sites.
Smolle
J
J
Department of Dermatology, University of Graz, Austria.
Soyer
H P
HP
Smolle-Jüttner
F M
FM
Rieger
E
E
Kerl
H
H
D001317:Austria / Q000453:epidemiology; D004812:Epidemiologic Methods; D006801:Humans; D008545:Melanoma / Q000453:epidemiology / Q000556:secondary* / Q000601:surgery*; D009362:Neoplasm Metastasis; D009366:Neoplasm Seeding; D009360:Neoplastic Cells, Circulating; D012878:Skin Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery*