Histopathologic grading of adult medulloblastomas.
BACKGROUND
Histopathologic evaluation of the degree and extent of anaplasia is a useful prognostic parameter in pediatric medulloblastomas. Whether the same applies to adult medulloblastomas is not known.


METHODS
The study included 74 adult patients with histologically confirmed medulloblastomas and retrospectively reassessed 67 cases with available slides for the presence of nodularity, collagen deposition (desmoplasia without nodules), and degree and extent of anaplasia.


RESULTS
Patients included 43 men and 31 women with the following age distribution: 18-40 years (84%); 41-50 years (9%); and 51-70 years (7%). At last follow-up, 56 patients were alive with a mean follow-up of 6.3 years (range, 0.1-20.8 years). A variety of treatments were employed during the study period, including postoperative radiation (85%) and chemotherapy (27%). Precise treatment modalities were unknown in 12% of patients. Anaplasia was absent (34%), mild (34%), moderate (27%), or severe (5%). Severe anaplasia was diffuse in 2 cases and focal in 1, although in the latter cases severe anaplasia was diffusely present at the time of disease recurrence. Male sex was associated with decreased 10-year recurrence-free survival (40% vs 66%; P = .021) and overall survival (38% vs 68%; P = .005). Severe anaplasia at first resection was found to be an independent predictor of decreased recurrence-free survival (P = .005) and overall survival (P = .015).


CONCLUSIONS
The incidence of severe anaplasia in adult medulloblastomas is lower than in the pediatric population. Male sex and the presence of severe anaplasia at the time of first resection are predictors of decreased recurrence-free and overall survival. However, the significance of severe anaplasia should be regarded with caution based on the small number of tumors with this feature in the current study.
Rodriguez
Fausto J
FJ
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Eberhart
Charles
C
O'Neill
Brian Patrick
BP
Slezak
Jeff
J
Burger
Peter C
PC
Goldthwaite
Patricia
P
Wu
Wenting
W
Giannini
Caterina
C
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002528:Cerebellar Neoplasms / Q000145:classification* / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D008297:Male; D008527:Medulloblastoma / Q000145:classification* / Q000473:pathology; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D017678:Sex Distribution; D015996:Survival Rate