Page 59 - Sentinel lymph node biopsy in oral cavity cancer - Inne J. den Toom

Five years regional recurrence free survival The RRFS of END and SLNB patients divided by T stage showed no significant differences between both groups (Figure 2E). However, when comparing the RRFS for the END and SLNB groups divided by anatomical location (FOM vs. other anatomical locations), a significant shorter RRFS was observed for the SLNB FOM group as compared to the END FOM group (88% and 97%, p = 0.008, (p = 0.048 Bonferroni corrected) Figure 2F). Additional metastasis in the MRND after a positive SLNB A histopathologically positive SLNB was found in 107 of the 488 patients (22%). ITCs 3 were detected as largest metastatic deposit in SLNB in 15 patients (14%), MiM in 31 patients (29%) and MaM in 61 patients (57%). A positive SLNB was followed by an additional (selective) neck dissection in 86% of the patients (92/107). Five patients refused any additional treatment (1x MiM, 4x MaM), and the remaining 10 patients received additional radiotherapy instead of a neck dissection. Radiotherapy was required for primary tumour control in 5 cases (2x ITC, 1x MiM, 2x MaM) and was therefore extended to the neck. In 4 cases (1x MiM and 3x MaM), radiotherapy was initiated because of 2 or more positive SLNs or extranodal extension, and in 1 patient (MiM) extensive surgery was not considered feasible due to major comorbidities. None of these 10 patients developed regional recurrences during follow-up. Additional non-SLN metastases were found in the neck dissection specimen in 21% of the patients (19/92) with a therapeutic neck dissection after SNLB. Of these patients, the majority (17/19, 90%) had MaM in the SLN as largest tumour deposit. Patients had a very low risk of having additional metastases if the SLN contained ITCs (8%, 1/13) or MiM (4%, 1/27) compared to MaM (33%, 17/52) (Table 3, p = 0.005). Disease specific survival per size of metastasis (ITC, MiM and MaM) did not reach significance, although a trend between ITC and MaM was observed (p = 0.091, Bonferonni corrected p = 0.182). 57