Læknablaðið - 15.06.2005, Page 45

FRÆÐIGREINAR / NYR DOKTOR
Nýr doktor í læknisfræði frá HÍ
Föstudaginn 6. maí síðastliðinn varði Tómas Guð-
bjartsson doktorsritgerð sína við læknadeild Há-
skóla íslands. Ritgerðin er um nýrnafrumukrabba-
mein og ber heitið Renal Cell Carcinoma in Iceland:
Incidence, prognosis, inheritance and treatment.
Andmælendur voru Jón Gunnlaugur Jónasson, dós-
ent og yfirlæknir Krabbameinsskrár KI og prófessor
Börje Ljungberg í Umeá í Svíþjóð. Athöfninni stýrði
Stefán B. Sigurðsson deildarforseti læknadeildar.
Það færist nú smám saman í vöxt að íslenskir læknar
taki doktorspróf frá HÍ. Þeir Magnús Gottfreðsson,
Ólafur Baldursson og Davíð O. Amar eru allir með
íslenskt doktorspróf.
Hér fer á eftir enskt ágrip doktorsritgerðarinnar.
Jón Gunnlaugur Jónasson, dósent og yfirlœknir Krabba-
meinsskrár KI og prófessor Börje Ljungberg frá Umeá-
háskólanum í Svíþjóð ásamt doktorsefninu.
Renal Cell Carcinoma (RCC) is by far the most
common malignant tumor of the kidney. The clinical
behavior of RCC is often unpredictable, and less is
known about its etiology and risk factors than for
most other human cancers.
The aim was to analyze clinicopathological risk
factors of RCC in all patients that had been diag-
nosed with RCC in lceland between 1971 and 2000,
including assessment of early results of nephrec-
tomy for RCC. An additional aim was to analyze
the genetic contribution of RCC in the lcelandic
population and the effect of incidental detection on
survival.
Clinical information was gained from patient
charts, their disease was staged according to degree
of spread, and the histology was reviewed. Both
overall survival and disease-specific survival were
analyzed and prognostic factors were evaluated in a
multi-variate analysis. For assessment of inheritance,
an extended genealogy database was used and rela-
tive risks and kinship coefficients were calculated.
It was concluded that stage is the most im-
portant prognostic factor of survival for RCC, with
nuclear grade adding to the prognostic information
about stage. Advanced age of the patient and early
calendar year of diagnosis are negative prognostic
factors of survival. However, after correcting for
grade and especially stage, the histological sub-
type, tumor size and venous thrombosis lost their
significance as independent prognostic factors.
Incidental detection increased more than threefold
during the study period, with 37% of patients being
diagnosed by coincidence after 1995, mostly due
to increased use of abdominal imaging for unre-
lated disease. The increase was most prominent
after 1990 and resulted in a significantly improved
survival in the last decade of the study. A similar in-
crease after 1990 was seen regarding both inciden-
tal detection and survival for both sexes together,
with a stable mortality rate. However, increased
incidence was only seen in males, indicating that
factors other than increase in incidental detection
could be involved in improving survival, at least for
women. On the other hand, incidental detection
was not found to be an independent prognostic
factor of survival, which suggests that incidentally-
detected RCCs have a similar biological behavior to
symptomatic RCCs, but are only detected earlier.
Familial aggregation analysis suggested that there
is a significant genetic contribution in the majority
of sporadic RCCs in lceland, both for members of
the extended family of an affected individual and
for close family members. Operative mortality after
nephrectomy for RCC has remained low for three
decades, and is most often caused by perioperative
bleeding and infections. Oncocytomas account for
5.5% of the total number of RCCs in lceland and,
in contrast to the latter, behave clinically as benign
kidney tumors.
The fact that every third patient has metastasis
at diagnosis affects the prognosis for the whole
group of RCC patients, with almost every other pa-
tient dying out of the disease within five years from
diagnosis (57% 5-year disease-specific survival).
However, survival of RCC patients is improving in
lceland, demonstrated with increased incidence
and stationary mortality. The main reason for this
trend is increase in incidental detection, the inci-
dentally diagnosed tumors being smaller and diag-
nosed at lower stages than symptomatic RCCs.
Renal Cell Carcinoma
in lceland
IncHhHico, prognoni*. iiiherllanc«
Forsíða ritgerðarinnar.
Tómas Guðbjartsson út-
skýrir efnivið sinn við
doktorsvörnina í hátíðar-
sal Háskóla íslands.
Læknablaðið 2005/91 533