NcXHF

SANDRO V. PORCEDDU
ADJUVANT RADIATION THERAPY
High-level randomized evidence confırming the benefıt of
adjuvant RT in advanced NMSC is lacking. NCCN clinical
practice guidelines in oncology for NMSC acknowledge
this fact, stating that its recommendations are based on
low-level evidence (the evidence is in the 2A category,
meaning there is uniform NCCN consensus that the intervention
is appropriate). 6
The use of adjuvant RT is based on data from retrospective
studies (which are acknowledged to be inherently biased)
that have shown that adjuvant RT reduces rates of recurrence
when used in advanced disease, such as regional nodal metastatic
cSCC. 13,15-18 There is a lack of universal guidelines that
describe which adverse prognostic factors warrant adjuvant
RT therapy and, therefore, the use of this therapy is typically
based on institutional policy. The Trans Tasman Radiation
Oncology Group has completed accrual to a randomized trial
(TROG 05.01 NCT00193895) comparing the role of adjuvant
concurrent chemoradiotherapy with the role of adjuvant RT
in high-risk cSCC. High-risk disease was defıned as and stratifıed
into locally advanced primary disease (AJCC or UICC
stage T3-T4or in-transit disease) and high-risk nodal disease
(defıned as any of the following: extracapsular extension
of any node size, intraparotid nodal metastasis
regardless of size or number, two or more cervical nodes,
and/or cervical node(s) that are 3 cm or larger). RT consisted
of 60 Gy over 6 weeks, with 2 Gy fractions daily, with or without
weekly carboplatin (AUC 2).
Table 4 summarizes indications where adjuvant RT may be
considered. However, Table 4 does not include a number of
other clinicopathologic prognostic factors for relapse, including
lymphovascular invasion, rapid growth, and pPNI.
These factors have been left out because there remains a
question about the benefıt of adjuvant RT in the presence of
these factors and about the extent of disease where the benefıt
is seen.
ADJUVANT REGIONAL NODAL TREATMENT
Intraparotid and cervical nodes are the most common regional
nodal basins involved in cSCC of the head and neck.
Veness et al found that among patients whose cSCC had metastasized
to lymph nodes, those who were receiving surgery/RT
had a statistically superior 5-year disease free
survival compared to patients receiving surgery alone (73%
vs. 54%, respectively; p 0.004). 18
Unlike in mucosal head and neck SCC, the role of adjuvant
chemoradiotherapy in high-risk disease is unknown. However,
based on the NCCN guidelines and publications from
Cooper et al and Bernier et al, some institutions have adopted
the use of adjuvant chemoradiotherapy for highrisk
disease, particularly in the presence of regional nodal
metastatic SCC with extracapsular extension. 6,22,23 The
TROG 05.01 (NCT00193895) is the only randomized trial
currently examining the role of adjuvant chemoradiotherapy
in high-risk cSCC, with results expected mid-2016.
ELECTIVE NODAL TREATMENT
Elective nodal treatment is often considered when the perceived
risk for occult nodal involvement is around 15% to
20%. The risk for occult nodal involvement is based on the
presence of high-risk clinicopathologic prognostic factors. In
cases where regional nodal involvement is suspected, CT is
typically used to stage the neck. However, the sensitivity and
specifıcity of CT for nodal involvement is reduced when
nodal diameter is smaller than 1 cm. Positron emission tomography
(PET) appears to have a higher sensitivity and
specifıcity than CT in the nodal staging of mucosal head and
neck cancer. 24 It is likely that PET has a similar utility in
cSCC, but this is yet to be confırmed in clinical studies.
Elective nodal treatment may consist of either elective
nodal dissection, or, in cases where adjuvant RT is recommended
for the primary site, the nodal basin may be treated
electively with RT at the same time.
Although there is some evidence showing that sentinel
lymph node biopsy may improve the detection of occult
node disease, its routine use is not currently universally
practiced. 25
TABLE 4. Clinicopathologic Factors Indicating
Consideration of Adjuvant Radiation Therapy*
UICC/AJCC stages T3-T4 or in-transit disease
Clinical perineural invasion
Recurrent primary disease
High-risk nodal disease
Immunosuppression
Abbreviations: AJCC, American Joint Committee on Cancer; UICC, Union for International
Cancer Control.
*Postoperative radiation therapy is considered for sites where margins are incomplete or
close ( 5 mm) and further surgery is not feasible or preferred.
ADJUVANT PERINEURAL INVASION TREATMENT
The challenge in managing patients with cPNI is in achieving
durable control. Despite the absence of randomized controlled
studies, en bloc resection and adjuvant RT may offer
select patients the best chance of cure. Tumors previously
considered unresectable, such as those with intracranial PNI
up to the gasserian ganglion (zone 2), may be operable and
have the potential to improve patient survival. 26 However,
this type of major surgery can require craniotomy, and thus is
best limited to appropriately selected patients in specialized
units. Furthermore, it is uncertain whether this type of surgery
has substantially greater benefıt compared with highly
conformal intensity-modulated RT alone. 27,28 The role of
elective nodal treatment and/or postoperative concurrent
chemotherapy and RT in cPNI in the absence of other adverse
risk factors remains inconclusive.
Gluck et al analyzed patterns of failure and proposed to include
the following in the target volume: the portions of the
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