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Page 2 of 14 Galli et al. J Cancer Metastasis Treat 2022;8:48 https://dx.doi.org/10.20517/2394-4722.2022.19

Conclusion: Both MRI and PET/CT afforded good negative predictive values for nodal staging in patients with
recurrent LSCC after (C)RT prior to STL. In selected patients, these radiological modalities, particularly PET/CT,
could help to avoid unnecessary surgery to the neck and its associated morbidity.

Keywords: Laryngeal squamous cell carcinoma, recurrence, salvage total laryngectomy, re-staging, neck dissection,
MRI, PET/CT, occult nodal metastasis

INTRODUCTION
[1]
Laryngeal squamous cell carcinomas (LSCC) account for approximately 25% of all head and neck cancers .
Management approaches for LSCC depend on several factors, including tumor stage and the patient’s
comorbidities. Since the early 1990s, organ-preserving strategies encompassing primary radiotherapy with
or without concomitant chemotherapy [(C)RT] have been alternatives to primary surgery for
advanced-stage LSCC .
[2-4]
Recurrences after (C)RT occur in approximately one-third of advanced cases and are most often local. In
such scenarios, salvage total laryngectomy (STL) is usually the only curative option available .
[5]

Staging and management of the previously irradiated neck in recurrent LSCC remains challenging because
[6-8]
of the tissue changes induced by (C)RT, including edema and fibrosis . In the absence of clinically
detectable neck lymph node (LN) metastases, it remains unclear whether the risk of occult neck metastases
warrants elective neck dissection (ND) and its associated morbidity. On one hand, missed metastases can
potentially lead to decreased disease control, especially considering that most patients do not qualify for
adjuvant therapy following STL (i.e. re-irradiation), whereas on the other hand, ND after (C)RT carries
significant morbidity, including wound healing disorders, injury to cranial nerves (marginal mandibular
branch of the facial nerve, hypoglossal nerve, and spinal accessory nerve) and chyle leak [9,10] . Moreover, ND
increases the risk of pharyngocutaneous fistula when performed along with STL [9,11] .

In this context, a number of studies have addressed the question of whether or not ND is needed at the time
of STL in patients with rcN0 necks. Reported rates of occult nodal metastases in recurrent LSCC range from
0% up to 28% [12,13] . The conclusions of these studies are discordant, with some authors favoring ND [14,15] ,
whereas others advocate a watchful surveillance of the neck instead [12,16,17] .

To date, only a limited number of studies have focused on the diagnostic value of currently used
radiological modalities for re-staging of the neck, namely magnetic resonance imaging (MRI) and
18F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT). Both modalities
are key elements in the decision-making process in patients with recurrent head and neck squamous cell
carcinoma. A recent study by Rosko et al. showed that PET/CT for neck re-staging in recurrent LSCC had a
low sensitivity of 16.7% but high specificity of 97.1%, and rather low positive predictive value (PPV) of
[18]
66.7% and negative predictive value (NPV) of 76.7% . The role of MRI in this disease setting has not yet
been comprehensively explored.

The aim of the current study was to assess the rate of occult neck node metastases in PET/CT-negative and
MRI-negative neck node disease in a cohort of patients with recurrent LSCC who underwent STL and ND,
and to examine the diagnostic value of MRI and PET/CT for neck node re-staging with histopathological
evaluation used as the reference standard.

METHODS