2017 Section 7 Green Book

C. Schilling et al. / European Journal of Cancer 51 (2015) 2777 e 2784

Table 2 SENT patient demographics and tumour characteristics. Characteristic Overall n Z

Negative SNB

Positive SNB

Effect of characteristic on sentinel node status

Total patients

415

321 (77%) 194 (60%) 127(40%) 61(28 e 92)

94 (23%) 53 (56%) 41 (44%)

Gender p Z 0.48

Male

247 (60%) 168 (40%) 61 (28-92)

Female

Age p Z 0.74

62 (29 e 91)

Median age (years, range) Primary tumour site Oral tongue anterior 2/3

Topographic site p Z 0.1

213 (51%) 43 (10.5%)

157/213 (74%) 32/43(74%) 13/17 (76%) 87/101 (86%)

56/213(26%) 11/43 (26%) 4 /17(24%) 14/101 (14%)

Oral tongue posterior 1/3

Buccal mucosa Floor of mouth

17 (4%)

101 (25%)

Hard palate

3 (1%) 8 (2%)

3/3 (100%) 4/8 (50%) 6 /6 (100%) 5/5 (100%) 6/9 (66%) 8/10 (80%)

0

Lower alveolus/gingival

4/8(50%)

Lower lip

6 (1.5%) 5 (1%) 9 (2%) 10 (2%)

0 0

Upper alveolus/gingival

Retromolar Soft palate

3/9 (33%) 2/10 (20%)

T stage T1

T stage p Z 0.032

296 (71%) 119 (29%)

239 (74%) 82 (26%)

57 (61%) 37(39%)

T2

Neck dissection (for SNB þ or recurrent disease) Yes 121(29%)

27(8%)

94 (100%)

N/A

No 0 Radiotherapy (n Z 36) or chemoradiotherapy (n Z 12) ( > 1 positive node, ECS or recurrence) Yes 48 (12%) 23 (7%) 25 (27%) 294(71%) 294 (92%)

N/A

No

367 (88%)

298(93%)

69 (73%)

Statistical testing by chi-square or two-sample t-test depending upon characteristic. SENT, Sentinel European Node Trial; SN, sentinel node; SNB, sentinel node biopsy; N/A, not applicable; ECS, extracapsular spread.

level. Demographic data, pathological features, location of SN, and survival data were collected for each patient. Statistical analysis was performed using R survival package [19] . Univariate survival analysis models were built using Kaplan e Meier product-limit estimator for overall survival (OS), disease-specific survival (DSS) and DFS, and multivariate and models with univariate continuous covariates were built using Cox proportional hazards model. Table analysis on 3-year outcomes (such as recurrence within 3 years of SNB) was performed using either chi-square or Fisher’ exact to test signifi- cance, depending upon the distribution of the variable in question.

(9 cases) exclusively to the contralateral neck. Sixty percent (28 in 46) of midline lesions drained bilaterally.

3.2. Occult cervical disease

SNB detected metastasis in 94 patients (23%), 16 of whom had extra-capsular spread (17%). Of the 75 cases classified by the UICC guidelines, 12 (16%) contained ITC, 36 (48%) contained micrometastasis and 27 (36%) macrometastasis. Fifteen patients with a negative SNB subsequently developed isolated cervical metastasis with a negative primary tumour site (one with concomitant distant metastasis) and these were recorded as a false-negative biopsy. Therefore, of 415 patients, 109 had occult metastasis. SNB had a sensitivity, negative predictive value and FNR of 86%, 95%, and 14%, respectively. The FNR, sensitivity and negative predictive value for the three most common tumour sites are shown in Table 3 . In the 49 patients with unexpected bilateral or contralateral drainage from a lateral carcinoma, a pos- itive SN was identified in seven (two bilateral and five solely contralateral). All 94 patients with a positive SNB underwent neck dissection. In seven cases, dissection was bilateral, giving a total of 101 neck dissections, of which 47% (47 in 101) were selective, and the remainder modified radical. In 85% of cases, no further positive nodes were found in the completion specimen. Of the patients with additional

3. Results

The patient and carcinoma characteristics are shown in Table 2 .

3.1. Lymphatic drainage characteristics

A total of 483 neck sides were examined from 415 patients with 1342 SNs harvested. There were a mean of 2.75 SN per neck or 3.2 SN per patient (range 1 e 10), with an average size of 11.8 mm (range 3 e 30 mm). The primary tumour was positioned in the midline in 11.4% (N Z 46) and laterally in 88.6% (N Z 369) of cases. Lateral tu- mours drained ipsilaterally in 87% of cases (320 in 369) but in 10% (40 cases) they drained bilaterally and in 2.4%

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