Oropharyngeal cancer Flashcards

Question

What % of OPC pts have clinically +nodes? Clinically occult nodes? Bilat nodes?

Answer 1

∼75% of OPC pts have clinically+ nodes at presentation, 30%–50% have clinically occult nodes, and ∼30% have bilat nodes (especially BOT/midline).

Answer 2

T1: ≤2 cm T2: >2 cm, ≤4 cm T3: >4 cm or extension to lingual surface of epiglottis T4a (moderately advanced): invades larynx, deep/extrinsic tongue muscles, medial pterygoid, hard palate, mandible T4b (very advanced): invades lat pterygoid muscle, pterygoid plate, lat NPX, skull base, carotid encasement For p16+ OPC, T4a and T4b are combined into a single T4 designation.

Answer 3

``` N1: single ipsi, ≤3 cm, ENE(–) N2a: single ipsi, >3 cm, ≤6 cm, ENE(–) N2b: multiple ipsi, ≤6 cm, ENE(–) N2c: any bilat or contralat, ≤6 cm, ENE(–) N3a: any >6 cm, ENE(–) N3b: any clinically overt ENE(+) ```

Answer 4

``` Stage I: T1N0 Stage II: T2N0 Stage III: T3N0 or T1–3N1 Stage IVA: T4aN0–1 or T1–4aN2 Stage IVB: T4b any N or any T N3 Stage IVC: any T any N M1 ```

Answer 5

Clinical N1: any ipsi, ≤6 cm N2: any contra or bilat LNs, ≤6 cm N3: any >6 cm Pathologic N1: ≤4 LN positive N2: >4 LN positive

Answer 6

``` Clinical Stage I: T1–2 N0–1 Stage II: T1–2 N2 or T3 N0–2 Stage III: any T N3 or T4 any N Stage IV: M1 ``` ``` Pathologic Stage I: T1–2 N0–1 Stage II: T1–2 N2 or T3–T4 N0–1 Stage III: T3–4 N2 Stage IV: M1 ```

Answer 7

Based on RTOG 0129 and AJCC 8th edition staging: Early: stages I–II (cT1–2N0) and select III (T2N1) Intermediate/favorable: HPV(+) stages III–IV (without T2N1) in nonsmokers/drinkers, T3N0 (exophytic) regardless of HPV/smoking status Advanced/unfavorable: HPV(–) smokers with stages III–IV Dz, T4 Dz regardless of HPV/smoking status

Answer 8

Early oropharyngeal tumor Tx paradigm: surgical resection with selective neck dissection +/- PORT or definitive RT alone

Answer 9

Intermediate-group oropharyngeal tumor Tx paradigms: Sg +/- postop CRT, altered fractionation RT, and CRT (conventional fractionation)

Answer 10

Advanced/unfavorable oropharyngeal tumor Tx paradigm: CRT (conventional)

Answer 11

Rarely. WLE may suffice in the rare instance of a small (<1 cm), ant tonsillar pillar lesion.

Answer 12

Generally, no. Simple tonsillectomy is considered an excisional Bx and thus needs further definitive Tx. Radical tonsillectomy may be adequate in select cases but results in worse functional outcomes than RT.

Answer 13

Historically, labiotomy and mandibulotomy were required to gain access to the OPX, but there is growing experience with transoral approaches with transoral laser microsurgery (TLM) and transoral robotic surgery (TORS).

Answer 14

Similar to other H&N sites, PORT is generally for intermediate-risk factors such as T3–T4, LN+, LVSI, and PNI, while postop CRT is indicated for +margin or +ENE.

Answer 15

Unilat neck Tx can be considered if the lesion is well lateralized (T1–T2, <1 cm soft palate extension, no BOT involvement) and 1 or few regional ipsi nodes <6 cm based on multiple retrospective reviews showing a very low contralat failure rate (<3%).

Answer 16

Levels II–IV should always be included/irradiated; however, some data (Sanguineti G et al., IJROBP 2009) suggest that levels I and V may be omitted d/t a significantly lower incidence of nodal spread.

Answer 17

The main indication for a neck dissection after CRT is persistent nodal Dz that can be documented by fine-needle sampling, CT (at 4–6 wks), or PET/CT (at 10–12 wks).

Answer 18

Neck dissection should typically occur at 6–8 wks (12–15 wks if evaluated by PET/CT).

Answer 19

OPC pts should be simulated supine, with arms pulled inferiorly and the head extended with a bite block or stent. Contrast is recommended with CT.

Answer 20

Mouth opening, tongue depressing stent

Answer 21

Dental evaluation/fluoride prophylaxis, speech and swallow evaluation/exercises, and nutrition evaluation with a PEG tube if the pre-Tx weight loss is >10% over 3 mos

Answer 22

CTV high dose (CTVHD): primary tumor and nodal GTV with 0.5–1-cm margin CTV intermediate dose (CTVID): soft palate, adjacent parapharyngeal space, sup tonsillar pillars for lat tumors, and nodal levels adjoining involved nodes CTV elective dose (CTVED): levels II–IV, RP nodes. If node+, most include ipsi IB and V.

Answer 23

T1 and superficial T2N0: 66–70 Gy to CTVHD, 60 Gy to CTVID, and 54 Gy to CTVED, given in 30–35 fx over 6–7 wks >T2+ without chemo: (1) 70 Gy to CTVHD, 63 Gy to CTVID, and 56 Gy to CTVED given in 35 fx over 6 wks (per Danish Head and Neck Cancer Group [DAHANCA]); (2) 70 Gy to CTVHD, 60 Gy to CTVID, and 57 Gy to CTVED given in 33 fx >T3 or >N2 with chemo: 70 Gy to CTVHD, 63 Gy to CTVID, and 59.5 Gy to CTVED in 35 fx

Answer 24

RTOG 00–22 (Eisbruch A et al., IJROBP 2010) demonstrated excellent results with accelerated hypofractionated IMRT for early OPC: 2-yr LF rate was 9% (if major deviations, 50%; otherwise, 6%, SS).

Answer 25

In RTOG 00–22 (Eisbruch A et al., IJROBP 2010), RT was delivered with accelerated hypofractionated IMRT as follows: 66 Gy in 30 fx (2.2 Gy/fx) to the primary PTV and 54–60 Gy in 30 fx (1.8–2 Gy/fx) to the secondary PTV. Neck staging was clinical (not from CT); however, pts “upstaged” by CT (e.g., cN1 but N2 after CT) were also eligible.

Answer 26

RTOG 90–03 (Fu KK et al., IJROBP 2000): 1,073 pts with H&N cancers (10% OC, 60% OPX, 13% HPX) with stage III (28%) or stage IV (68%) Dz randomized to (a) conventional 70 Gy qd, (b) 81.6 Gy in 1.2 Gy/fx bid, (c) accelerated with split, and (d) concomitant boost (1.8 Gy/fx qd × 17, with last 12 fx bid with 1.8 Gy AM, 1.5 Gy PM to 72 Gy). There was better LC with altered fx (54% vs. 46%) but no OS/DFS benefit. There was worse acute toxicity but no difference in late toxicity.

Answer 27

``` RTOG 90–03 (Fu KK et al., IJROBP 2000): see above. EORTC 22791 (Horiot JC et al., Radiother Oncol 1992): 325 pts (all OPX, but no BOT): 70 Gy vs. 80.5 Gy at 1.15 Gy bid. There was better LC (60% vs. 40%) but no OS benefit. LC was best for T3 Dz. ```

Answer 28

MDACC data (Garden AS et al., Cancer 2004): pts with small primaries but stages III–IV Dz by virtue of +LNs; treated with RT alone. There were acceptable 5-yr LF (15%), DM (19%), and OS (64%) rates.

Answer 29

GORTEC 94–01 (Calais G et al., JNCI 1999): 222 pts with stages III–IV OPC randomized to conventional RT alone vs. conventional RT + carboplatin/5-FU, no planned neck dissection for N2–3 Dz. The CRT arm had better 3-yr OS (51% vs. 31%), DFS (30% vs. 15%), and LC (66% vs. 42%); however, there was significantly worse grades 3–4 mucositis and weight loss/feeding tube use in the CRT arm. Head and Neck Intergroup Study (Adelstein DJ et al., JCO 2003): 295 pts with unresectable stages III–IV H&N cancers (15% OC, 55% OPX, 20% HPX), RT alone vs. CRT with cisplatin 100 mg q3 wks × 3. 3-yr OS was better in the CRT arm (37% vs. 23%). There also was improved DFS (51% vs. 33%) in the CRT arm.

Answer 30

EORTC 22931 (Bernier J et al., NEJM 2004): 334 pts randomized to PORT 66 Gy vs. PORT + cisplatin 100 mg/m2 on days 1, 22, and 43. Eligibility: ECE, +margin, PNI, LVI, and levels 4–5 +N from OCC/OPC. There was better OS, DFS, and 5-yr LC with CRT but ↑ grades 3–4 toxicity. RTOG 95–01 (Cooper JS et al., NEJM 2004): 459 pts randomized to 60–66 Gy PORT vs. PORT + cisplatin 100 mg/m2 on days 1, 22, and 43. Eligibility: >2 LN, ECE, +margin. There was better DFS (43% vs. 54%) and 2-yr LRC (72% vs. 82%) but only a trend to improvement in OS (57% vs. 63%).

Answer 31

Bonner JA et al. (NEJM 2006): 424 pts with stages III–IV SCC of the OPX, laryngeal cancer, or HPX randomized to RT vs. RT + C225. RT options were conventional to 70 Gy, 1.2 bid to 72–76.8 Gy, or concomitant boost to 72 Gy. There was better 3-yr LRC (47% vs. 34%) and OS (55% vs. 45%) with C225 + RT. Subset analysis showed improvement mostly in OPC and in the altered fractionation RT arms (∼50% treated with altered fractionation).

Answer 32

1. E1308: Phase II, stages III/IV, induction chemo (paclitaxel, cisplatin,cetuximab) f/b 54 Gy in 27 fx if CR or 69.3 Gy in 33 fx if PR, both with concurrent cetuximab. Although the study (Marur S et al., J Clin Oncol 2017) met its 2-yr PFS target based on historical control, other phase III trials indicate induction chemo adds toxicity without survival benefit (PARADIGM, DeCIDE). 2. RTOG 1016: Phase III, stages III/IV, treated with accelerated IMRT to 70 Gy/6 wks randomized to concurrent cisplatin vs. cetuximab. 3. NRG HN002: Phase II, stages III/IV, randomized to dose-reduced cisplatin CRT (60 Gy in 6 wks) vs. accelerated RT alone (60 Gy in 5 wks).

Answer 33

TAX 324 study (induction chemo → CRT) (Posner MR et al., NEJM 2007): 501 pts, unresectable stages III–IV H&N cancers (52% OPX, 13%–18% OC, larynx, HPX) randomized to induction platinum + 5-FU or TPF → CRT with carboplatin. There was better 3-yr OS (62% vs. 48%), MS (71 mos vs. 30 mos), and LRC (70% vs. 62%) in the TPF arm. Pts in the TPF arm had fewer Tx delays than in the platinum/5-FU arm despite higher myelotoxicity in the TPF arm (98% rcvd planned Tx in the TPF arm vs. 90% in the PF arm). TAX 323 study (induction chemo → RT) (Vermorken JB et al., NEJM 2007): 358 pts, unresectable stages III–IV H&N cancers (46% OPX, 18% OC, 29% HPX, 7% larynx) randomized to induction platinum + 5-FU or TPF → RT alone. TPF resulted in better median PFS (11 mos vs. 8.2 mos), MS (18.8 mos vs. 14.5 mos), and HR 0.73. The rate of toxic deaths was greater in the platinum/5-FU group (5.5% vs. 2.3%). Also, there was more grades 3–4 thrombocytopenia, anemia, stomatitis, n/v, diarrhea, and hearing loss in the platinum/5-FU arm. Neutropenia, leukopenia, and alopecia were more common in the TPF arm.

Answer 34

``` PARADIGM study (induction TPF → CRT vs. CRT) (Haddad H et al., Lancet Oncol 2013): 145 pts, stages III–IV (55% OPX), randomized to induction TPF → CRT vs. CRT. At a median follow-up of 49 mos, there was no difference in 3-yr OS (73% for induction vs. 78% for CRT), with a higher rate of febrile neutropenia observed in the induction arm. ```

Answer 35

There is potentially better laryngeal sparing with split-field IMRT techniques; however, the drawback is that the practitioner may have to junction the RT dose through involved nodes.

Answer 36

The main advantage of IMRT dose painting is that better conformality can be achieved in a single plan. The drawback, however, is that nonstandard doses/fx are required.

Answer 37

Each wk of Tx-time prolongation reduces the LC rate by ∼10%–12% in H&N cancer pts b/c of accelerated repopulation

Answer 38

According to Bese NS et al. the best way to compensate is by preserving total time, dose, and dose/fx (i.e., can treat bid on Fridays or extra fx on Saturdays). Alternatively, dose/fx can be increased (e.g., by 0.5–0.7 Gy/day). (IJROBP 2007)

Answer 39

The long-term PEG tube dependency rate after CRT can be as high as 15%–20%, which is reduced with efforts on sparing swallowing structures (pharyngeal constrictors, larynx) with swallowing exercises and the use of PEG on demand.

Answer 40

Typical RT dose constraints for the parotid glands are (a) mean dose to either parotid <26 Gy or (b) at least 50% of either parotid gland <30 Gy.

Answer 41

The mean dose to the inner ears should be ≤35 Gy.

Answer 42

∼30% of pts will experience hearing loss.

Answer 43

Xerostomia rates in RTOG 00–22 (Eisbruch A et al., IJROBP 2010) were 55% at 6 mos, 25% at 1 yr, and 16% at 2 yrs. Salivary output did not recover over time.

Answer 44

The observed rate of osteoradionecrosis was 6% in RTOG 00–22 (Eisbruch A et al., IJROBP 2010), which is higher than expected for IMRT (potentially b/c of the accelerated hypofractionated approach). Other toxicities were acceptable (grade 2+ for mucosa [24%], salivary [67%], esophagus [19%]).

Answer 45

Fluoride trays. Consult a dental oncologist before any dental procedures.

Answer 46

OPC follow-up paradigm: H&P + pharyngolaryngoscopy (q1–3 mos for yr 1, q2–6 mos for yr 2, q4–8 mos for yrs 3–5, q12 mos if >5 yrs), imaging (for signs/Sx), annual TSH, speech/hearing/dental evaluation, and smoking cessation.

Oropharyngeal cancer Flashcards

(70 cards)