Quand et comment traiter un « gliome de bas grade » ?

Effets à long terme de la chimiothérapie chez 7 patients présentant un gliome de bas grade symptomatique

INTRODUCTION

Whether aggressive treatment or no treatment is the optimal management for low-grade gliomas is controversial. However, symptomatic low-grade gliomas require prompt therapeutic intervention because of neurological impairment, uncontrolled seizures, and deterioration of life quality.

METHODS

We report the long-term follow-up, 71 months, of seven patients treated by procarbazine, lomustine and vincristine (PCV) therapy for a symptomatic low-grade oligodendrogliomatous tumor. The mean age at diagnosis was 47 years, the mean time from first symptoms to initiation of PCV therapy was 62 months (range 15-147).

RESULTS

All patients initially responded favorably, with improvement of the neurological symptoms and radiological response. Chemotherapy was clinically well tolerated, the main side effect being low hematological toxicity. During the follow-up, no progression was observed in two patients. For the five remaining patients, the time to progression after the PCV induction was 56+/-12 months (range 38 to 73). Four of these patients showed favorable response to a second line of treatment.

CONCLUSION

PCV therapy is an interesting therapeutic option for progressively symptomatic low-grade gliomas, even in cases with large tumoral volume. This treatment, of moderate toxicity, improves the quality of life and can result in long-term tumor stabilization.

[Adult supratentorial oligodendrogliomas. Surgical treatment: indications and techniques]

Surgical resection is the first step in the treatment of adult supratentorial oligodendrogliomas (OLG). However, the role of resection on prognosis, the most appropriate time for surgery along the natural history of those tumors, and the best operative strategy remain debated. Survival curves after resection vary greatly among reported series, in particular as a result of a persisting confusion in identification and classification of cerebral OLG. Surgical or stereotactic biopsy is the first surgical procedure which enables confirmation of the diagnosis suggested on imaging, assessment of extension of tumor cell infiltration beyond abnormalities limit described an imaging, and currently available molecular biology studies. Biopsies may be the only surgical procedure in patients having a deep-seated tumor with minimal mass effect, or prior to a surgical resection or a "wait and watch" strategy. Surgical resection is indicated for the other patients. However, it has not been demonstrated that time for resection has an influence on survival, excepted in patients with rapidly growing tumors, with mass effect causing increased intracranial pressure. A wait and watch strategy is therefore warranted in patients with a tumor aspect suggestive of a grade A OLG; surgical resection may be indicated later. There is a current trend for maximal safe resection, preserving functional cerebral areas, since truly complete resection of the tumor including infiltration is exceptional. However, from the contradictory results reported to date, one cannot ascertain whether large or complete resection based on imaging is associated with significantly longer survival. Neuronavigation guidance, intraoperative imaging, and cortical stimulation techniques are helpful neurosurgical techniques enabling maximal safe resection with preservation of functional areas.