Necessity of Intraoperative Level IIA Lymph Node Dissection in Patients with Carotid Body Tumors: A Retrospective Study of 126 Cases

Abstract

<b><i>Background:</i></b> Carotid body tumors (CBTs) are relatively uncommon neoplasms that rarely have malignant potential. However, malignant CBTs (MCBTs) are still associated with a poor prognosis and the treatment is still challenging clinically. Therefore, we evaluated the necessity of intraoperative level IIA lymph node dissection in patients with CBT. <b><i>Methods:</i></b> The clinical characteristics, intraoperative details, and pathological diagnosis of 126 CBT patients who had undergone surgery were retrospectively reviewed. The patients were divided into 2 groups according to whether level IIA lymph node dissection was performed. The prognosis was analyzed using Kaplan-Meier curves and Cox model multivariate survival analysis. <b><i>Results:</i></b> Among the 126 patients, 7 patients (10.3%) in the selective lymph node dissection (SLND) group (68 patients) were diagnosed with MCBTs with evidence of lymph node metastasis. Two patients (3.4%) in the lymph node nondissection (LNND) group (58 patients) were diagnosed with MCBTs later after the second operation because they could not be diagnosed as malignant initially because of the lack of lymph node pathology results although the pathology of the primary lesion showed features of malignancy. The SLND group had a significantly higher relapse-free survival rate than the LNND group (94.1% vs. 79.3%, <i>p</i> = 0.021). Patients with a confirmed diagnosis had a better prognosis than those with insufficient evidence of a malignancy due to the lack of lymph node information. Twenty-nine patients in the SLND group and 26 patients in the LNND group had postoperative nerve injuries, with no significant difference between the groups (<i>p</i> = 0.879). <b><i>Conclusion:</i></b> Intraoperative dissection of level IIA lymph nodes around the tumor in CBT patients can help improve the diagnosis and prognosis of MCBTs without causing additional cranial nerve injury.

Clinicopathological characteristics of patients with carotid body tumor with cervical lymph node metastasis: A retrospective study of 10 cases and review of the literature

“…Some suggest that concomitant lymph node dissection does not appear to add value in the absence of clinical suspicion for malignancy, yet a recent study showed that intraoperative dissection of level IIA lymph nodes in CBT patients might contribute to the diagnosis and prognosis of MCBTs. [24,25] Distant spread was rare in our reported cases. When the primary tumor and locoregional lymph nodes were excised, neither further regional lymph node metastasis nor distant spread was observed during long-term follow-up in most cases.…”

Malignant carotid body tumors: What we know, what we do, and what we need to achieve. A systematic review of the literature

“…Finally, 132 papers were considered appropriate for the present SR, for a total of 337 patients (Figure 1). Among these articles, 20 (158 patients) included 5 or more patients (Table 1) 18–39 and were considered for the proportion MA. The remaining 112 studies (179 patients), represented by case reports or case series with <5 patients, are reported in Table S1 3,40–152 …”

“…Overall, 158 patients with MCBTs were included in the MA from the 20 case series with five or more patients 18–39 . The diagnosis of MCBT in these surgical series was a rare occurrence, with a pooled proportion of 7.3% (95% CI: 5.8%–8.9%; I 2 = 33%).…”

“…For proportion meta‐analysis (MA), only case series with at least five consecutive cases were considered (Table 1). 18–39 All the other case series describing less than five patients (including case reports) were considered only for the SR and detailed in Table S1 3,40–152 …”

“…Therefore, future directions to anticipate as much as possible the diagnosis of MCBTs should include: (1) at the patient level, in every cervical paraganglioma carrier, systematically addressing possible genetic mutations, testing catecholamine secretion, and intensively searching for possible multifocal disease since these are all well-known risk factors for an increased malignant potential 166,167 ; (2) at the tumor level, continuing the search for possible hallmarks predictive of the malignant potential of such lesions, for example quantifying superoxide anions (whose higher concentration is directly linked to SDHx mutations and ensuing more frequent DNA mutations) within the CBT surgical specimen using a fluorogenic dye as recently described by Kajal and coworkers 168 or evaluating the matrix metalloproteinases-1, -2, and -3 levels in plasma and tissue samples (found to be significantly higher in MCBTs by Serra et al) 91 ; (3) at the nodal level, following the recommendations of performing at least a prophylactic level IIA sampling, potentially extended to a selective neck dissection of levels II-III for diagnostic purposes in every CBT 30,37,70,81,138,159,169,170 ; (4) at the metastatic level, applying as much as possible a diagnostic work-up and/or follow-up including Gallium 68 labeled 1,4,7,10-tetraazacy-cloDOdecane-1,4,7,10-Tetraacetic Acid-NaI-OCtreotide Positron Emission Tomography/Computed Tomography (Ga-68 DOTANOC PET/CT). 171 As a general rule, special attention to exclude MCBT should be given to lesions with presentation at the extremes of age, gross infiltrative and aggressive behavior into the surrounding neck structures, multifocal nature, association with family history (in particular SDHB or SDHD genes mutations), and size >4 cm with Shamblin III classification (Figure 5A,B).…”