**4. Data of the personal series**

Thirty-three patients with multicentric-diffuse recurrences of meningiomas are included in our series [28] (**Tables 1**-**3** and **Figures 1-3**). They are 22 females (67%) and 11 males (33%), with a median age of 52 years. The findings at initial surgery were as follows (**Table 1**). The most frequent location was non skull-base (55%), followed by lateral (36%) and medial skull-base (9%). The tumor was mostly flat-shaped (76%) and less frequently round (24%). Complete resection (Simpson grades 1 and 2) at initial surgery was obtained in 23 among 33 patients (70%).

The pathological findings at initial diagnosis (**Table 1**) showed 52% of WHO [35] grade I and 48% of grade II tumors; the Ki67-Li was <4% in 20% and ≥ 4%in 80%. The PR expression was ≤50% in 82% of specimens and > 50% in 9%.

When compared to the findings of meningiomas which showed localizedperipheral recurrences, only the higher rates of flat-shaped tumors (p = 0.0008) and tumors with Ki67-Li ≥4% (p = 0.037) were significant [28].

The management and outcome of the recurrences were as follows (**Table 2**). Twenty-five out of 33 patients (76%) were reoperated on and underwent one (48%) or two or three reoperations (52%) (**Figures 1** and **2**). The complete resection (Simpson grades I and II) was possible only in 5 among the 25 patients (20%). The histological WHO grade at first reoperation was similar to that of the initial surgery in 15 out of 25 patients (60%); progression to a higher grade was observed in 10 cases (40%).

Adjuvant treatments included external radiotherapy in 20 patients, stereotactic radiosurgery in 9 and chemotherapy in 5.

When compared to patients with localized-peripheral recurrences, those with multicentric-diffuse recurrences showed significantly higher number of reoperations (p = 0.0034), lower rate of gross total resection (p = 0.00001) and higher but not significant rate of cases with progression of the WHO grade (p = 0.09) [28].

The actual follow-up ranges from 2 to 25 years. One patient died postoperatively for respiratory failure. Among the other 24 patients operated on, eleven (34%) are alive with local tumor control versus none out of eight patients who did not undergo surgery (p = 0.029). Six (25%) show slow tumor progression with no symptoms in spite the surgery. Seven patients of the surgical group (29%) died during the follow-up (5 for tumor progression) versus 6 (for tumor progression) out of 8 (75%) of the non-surgical group (p = 0.038). Thus, among 25 patients reoperated on 17 (68%) are alive after one or more reoperations versus only 2 out of 8 (25%) who did not undergo surgery.


#### **Table 1.**

*Clinico-radiological, surgical and pathological findings at initial diagnosis (33 patients).*


*Topographic Distribution of Intracranial Meningioma's Recurrences: Localized Versus Diffuse… DOI: http://dx.doi.org/10.5772/intechopen.97120*


#### **Table 2.**

*Management of 33 patients with multicentric-diffuse recurrences.*


#### **Table 3.**

*Outcome of 33 patients with multicentric-diffuse meningioma recurrence.*

#### **Figure 1.**

*58 years old woman with history of previous resection of a WHO I grade meningioma of the left frontal convexity in 1991. (a) Postoperative CT after the initial surgery: no residual tumor; (b) Post-contrast MRI 21 years later: local multicentric recurrence at the previous dural site and distal recurrence at the left parietal region; (c) Postoperative MRI showing resection of both nodules (WHO grade I) and interposed dura.*

#### **Figure 2.**

*68 years old man who underwent resection of an anterior parasagittal WHO grade II meningioma in 2010. (a-d) Post-contrast MRI, T1 axial (a, d) and coronal (b, c) sequences: diffuse recurrences of the parasagittal and both convexity regions with significant tumor masses, at the left parasagittal and convexity and at the anterior temporal convexity. Two-stage resection of the masses and irradiation.*

**Figure 3.**

*(a-b) 72 years old man with history of a left spheno-orbital WHO grade II meningioma: a) preoperative T1 axial post-contrast MRI and (b) postoperative CT scan: complete resection. (c-d) Post-contrast T1 axial (c) and coronal (d) MRI sequences seven years after the initial surgery: large tumor recurrence involving the left orbital cavity and extending diffusely in the intracranial compartment at the suprasellar, left parasellar region and temporal fossa. Management by external radiotherapy.*
