2018-19 Section 7-Neoplastic and Inflammatory Diseases of the Head and Neck eBook

Oral Oncology 73 (2017) 152–159

K.Y. Zhan et al.

Table 1 Demographics, patient, and treatment characteristics (N = 3745).

Sex

Treatment overview

Male

3169 (84.6%) 576 (15.4%)

Surgery only Surgery + RT Surgery + CRT

642 (18.8%) 1005 (29.4%) 1773 (51.8%) 217 (5.8%) 456 (12.2%) 2612 (69.7%)

Female

Facility type

Community

214 (5.8%)

Extent of primary site surgery

Comprehensive community 1039 (28.3%)

No surgery

Academic

2117 (57.7%)

Local tumor excision

Limited, partial pharyngectomy a

Integrated network

300 (8.2%)

Race

Total pharyngectomy Radical pharyngectomy

341 (9.1%) 60 (1.6%) 59 (1.6%)

White Black Other

3534 (95.3%)

115 (3.1%) 59 (1.6%)

Surgery, NOS

Radiotherapy (n = 3726)

Insurance status (n = 3705)

No Yes

714 (19.1%) 3012 (80.4%)

Private

2577 (68.8%) 288 (7.7%) 779 (20.8%)

Uninsured, medicaid

Unknown

19 (0.5%)

Medicare

Chemotherapy (n = 3666)

Other

61 (1.6%) 40 (1.1%)

No Yes

1679 (44.8%) 1987 (53.1%)

Unknown

Charlson/Deyo score

Unknown

79 (2.1%)

0 1

3097 (82.7%) 535 (14.3%)

Oropharyngeal subsites

Base of tongue

1097 (29.3%) 2498 (66.7%)

≥ 2

113 (3%)

Tonsil

Soft palate

14 (0.4%) 136 (3.6%)

Other

a Limited/partial pharyngectomy includes unilateral or bilateral tonsillectomy; RT: Radiotherapy; CRT: Chemoradiation; NOS: Not otherwise speci fi ed.

pN1 (8%) or pN2 (7.7%). The majority of pN0 disease had pT2 lesions (51.6%). Pathologic T1 tumors comprised 32.3% of pN0 disease vs. 52% of pN1 and 46.3% of pN2s (p < 0.001). 41% of all pN+ cases (N = 1224/2980) had pathologic evidence of ENE. ENE was more common (p < 0.001) in pN2 disease (69.4%) than pN1 (35.5%). Within ENE cases, 48% were microscopic, 12.2% mac- roscopic, and 39.8% recorded as not otherwise speci fi ed (NOS). Table 3 displays a subgroup analysis within AJCC 8th edition staging. Once again, higher stages had higher incidence of chemotherapy and radio- therapy (both p < 0.001). Stage I had slightly higher incidence of fe- males compared to II-III (p < 0.001). No other notable statistical or clinically-relevant di ff erences were noted when comparing by in- surance type, facility type, or comorbidity scores. Median follow-up was 31.3 months, IQR (21.3 – 43.6 months). Fig. 2 compares OS for pathologic staging between the AJCC 7th and 8th editions. In the AJCC 7th edition, 4-year OS was 95%, 92%, 91%, and 88% for stages I-IV respectively (distant metastatic disease excluded, all pairwise p > 0.05). In contrast, 4-year OS was 92%, 81%, and 62% for the 8th edition for Stages I-III, all pairwise p < 0.01. Fig. 3 shows overall survival for AJCC 8th pN-staging changes, with 4-year OS as 88%, 91%, and 79% for pN0-N2. Of note, the pN0 and pN1 curves were not signi fi cantly di ff erent from each other, p = 0.065. ENE had a sig- ni fi cant negative e ff ect (p < 0.001) on survival ( Fig. 4 ), with 4-year OS being 92% (ENE − ) and 85% (ENE+). This e ff ect remained statis- tically signi fi cant when strati fi ed by N-stage for pN1 disease, with 4- year OS as follows: pN1 92% ENE − , 87% ENE+ (p = 0.004); pN2, 88% ENE − , 77% ENE+ (p = 0.061). Survival

Table 2 Comparison of T, N and overall staging distribution between AJCC 7th and 8th edi- tion.

AJCC 7th edition

T-stage a pT0, Tis, TX

150 (4.0%) 1747 (47%) 1453 (39.1%)

pT1 pT2 pT3 pT4

242 (6.5%) 121 (3.3%)

AJCC 7th edition

AJCC 8th edition

N-stage

N-stage

pN0 pN1 pN2 pN3

409 (11%) 643 (17.3%) 2527 (67.9%)

pN0 pN1 pN2

417 (11.5%) 2754 (75.9%) 456 (12.6%)

142 (3.8%)

pOverall stage I (8th ed.)

II (8th ed.) III (8th ed.) Totals

I (7th ed.) II (7th ed.) III (7th ed.) IV (7th ed.)

135 (3.6%) 248 (6.6%)

5 (0.1%)

0 0

140 (3.7%) 248 (6.6%)

0

609 (16.3%) 101 (2.7%) 1 (0.02%) 711 (19.0%) 2009 (53.7%) 557 (14.9%) 77 (2.1%) 2643 (70.6%) 3001 (80.2%) 663 (17.7%) 78 (2.1%) 3742 (100%)

Totals

a T-stage is unchanged between the 7th and 8th edition in our cohort.

pN0, p < 0.001). 60% of pN0 patients did not receive radiation compared to only 14% without radiotherapy in pN1 (p < 0.001). Most pN0 patients were treated with surgery alone (61.1%) vs. 8.2% of pN2 patients (p < 0.001); This trend was again seen from overall stage I to III (84.2% triple modality in stage III disease vs. 47.7% stage I). Distribution of T-stages di ff ered signi fi cantly by pN stage (p < 0.001). pT3-T4 lesions were more common in pN0 (16.1%) than

Discussion

We appraised the AJCC 8th edition pathological staging modi fi ca- tions for surgically-treated HPV+ OPSCC using a national cohort of

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