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of neck lymph node metastasis is the most significant The OSCC has a high incidence of micrometastases and often
prognostic and survival factor in patients with oral cavity bilaterally metastases due to the rich submucosal lymphatic
[8]
squamous cell carcinoma (OSCC). With the exception of plexus, that communicates freely crossing the middle line.
thin early-stage tumours in the context of clinically and It presents a variable incidence of CLNM between 0.9% to
radiologically node negative necks, most patients with 36%, reported in the literature. Diverse factors can be held
[1]
OSCC undergo neck dissection. This has the benefit responsible for such differences, among them the diversity
of treating occult metastatic disease and providing of the anatomic regions considered for study, problems
pathological staging information to direct adjuvant in clinical staging, and exclusion of cases not considered
therapy. [2,3] The rich lymphatic connections in the head eligible for treatment. Kowalski et al. found a rate of 36% of
[6]
and neck makes oral cavity malignancies susceptible to contralateral positive nodes after bilateral neck dissection.
[4]
spread across the midline. The SCC of the oral cavity Kurita et al. observed an incidence of CLNM in early oral
[5]
presents a variable frequency of contralateral lymph tongue SCC of 12.2%. In the paper reported by Koo et al.
[8]
neck metastases (CLNM) between 0.9% to 36%, reported the overall rate of occult contralateral metastasis in OSCC
in the literature. [5,6] The presence of such metastases was 11%, and the rate was 21% in cases of ipsilateral
decreases the survival rate of the patients, generating pathologic metastasis. In the study of Bier Laning et al.
[9]
a poor prognosis. Although elective treatment of the the incidence was 10%. This corresponds to the findings
[7]
contralateral neck is accepted for OSCC approaching of Mukherji et al. who found that oral tongue and
[10]
or crossing the midline, this is not routinely performed floor-of-mouth cancers had an expected drainage to
in lateralized cases. Few studies have analyzed rates of contralateral lymph nodes in up to 9% of cases. On the
contralateralneck disease in oral cancer and thefactors other hand, Lim et al. in their study detected only a
[11]
that may be involved with them. In terms of treatment 4% rate of contralateral occult metastases in a series of
decision-making, the use of elective contralateral neck early tongue carcinomas and did not recommend elective
dissection remains controversial for patients with OSCC contralateral neck treatment. González-García et al. in
[12]
that does not cross the midline. a large series of 315 patients with oral squamous cell
carcinoma of the oral cavity, reported an incidence rate of
The purpose of this review was to evaluate the incidence 5.7% for CLNM, which is similar to the 5-year CLNM rate of
of CLNM and analyze the factors that may predict their 4.1% reported by Feng et al. while another large cohort
[13]
appearance in OSCC to form a rational basis for elective study by Huang et al. showed a 7.1% 5-year CLNM rate.
[14]
contralateral neck management.
In relation to prognosis, it has been widely accepted that
METHODS CLNM dramatically reduce the long-term survival and
prognosis in these patients is described as extremely
To address the research purpose, the authors designed poor. [6,8,15,16] Capote-Moreno et al. reported a decrease
[7]
and implemented a systematic review of the literature. in the 5-year survival rate in patients with OSCC, from
The electronic search was perfomed in the Cochrane 70% in patients with negative contralateral lymph nodes
Library, MEDLINE via Pubmed and EMBASE using the to 41.2% in those with CLNM. These rates were similar
[8]
key terms “contralateral neck dissection”, “contralateral to those found by other authors; for example, Koo et al.
metastases”, “oral squamous cell carcinoma” and found a 5-year cause-specific survival rate of 43% in
“oral cancer”. Some of these terms were searched in patients with contralateral disease compared with 73%
combination. The references of each article obtained in metastasis-free patients in a series of 173 cases with
were checked for additional relevant studies. Only articles oral and oropharyngeal SCC, which emphasizes the
published in English were included in this study. One prognostic importance of CLNM.
reviewer screened all titles and abstracts. A total of 103
references were retrieved, of which 34 were screened. With respect to the time of appearance, most studies
The exclusion criteria were: (1) date of publication before corroborate that CLNM mainly happens within two years
1999; (2) articles written in a language different from postoperatively. [17-20] For instance, González-García et al. in
[20]
English; (3) required data not available; and (4) type of a series of 203 patients with oral squamous cell carcinoma
article: abstracts, letters, comments, editorials, expert of the tongue, with especial consideration in excluding
opinions or case reports. those cases involving the midline or at a distance less than
1 cm, reported CLNM occurring within the first 2 years
THE ROLE OF CLNM IN OSCC after surgery in 89.9% of the affected patients. Therefore,
special effort should be paid early detecting nodal relapse
The contralateral metastasis propagation can occur in in the cervical región,while a careful follow-up is mandatory
the head and neck carcinoma in different ways: firstly, during this period of time.
by crossing afferent lymphatic vessels, by tumor spread
along the midline, when ipsilateral lymph nodes are PREDICTIVE FACTORS
widely involved, and secondly, in certain anatomical
areas where there is not a real barrier in the midline. [7] Several clinical and pathological factors have been proposed
182 Plast Aesthet Res || Volume 3 || June 24, 2016