[Endocrine late-effects and bone mineral density after combined treatment of malignant brain tumors in childhood and adolescence].

BACKGROUND

The implementation of standardized protocols for combined treatment of cancer into clinical practice inevitably leads to a long-term consequence.

AIMS

To study the prevalence of endocrine disorders, to assess the prevalence and degree of decline of bone mineral density (BMD) in individuals who have undergone combined treatment of malignant brain tumors in childhood and adolescence.

MATERIALS AND METHODS

A retrospective study was conducted with 59 young adults (31 men; 28 women) who have undergone surgical treatment of malignant brain tumour followed by radiation treatment (craniospinal radiation in combination with or without polychemotherapy). Group I consisted of 37 patients, who were treated between the ages of 3 and 16 years. Group II included 22 patients who received treatment between the ages of 16 and 38 years.

RESULTS

GH deficiency according to the results of the insulin hypoglycemia test was diagnosed in 48 patients (81%), 22 -patients had secondary adrenal insufficiency (37%). The majority of those examined (33 patients (56%)) did not achieve the target growth. Only 5 people from I group was treated with recombinant GH. Correlation analysis demonstrates that age of treatment is the main factor affecting final growth (r=0,619, p<0,001). Many cases of hypothyroidism (n=39 (66%)) and hypogonadism (19 women; 17 men) were detected. According to the DXA, a decrease of BMD ≤-2.0 SD (Z-score) in L1-L4 was found in 35 of 59 patients (59%). The BMD in the I group was significantly lower than in patients treated at an older age (p<0.001). A moderate correlation was discovered between BMD in L1-L4 at the time of examination and the level of estradiol in women (r=0.596, p<0.05) and testosterone in men (r=0.472, p<0.05). Direct correlation between BMD and age of diagnosis was revealed (r=0.781, p<0.01).

CONCLUSIONS

The results show that patients need to be monitored annually and for life after the combined treatment of malignant brain tumors in order to detect the long-term effects of the treatment. The high incidence of osteopenic conditions determines the relevance and need for early diagnosis to prevent further bone loss, reduced bone strength and the risk of fractures.