SURGERY OF THE LYMPH NODE STATIONS IN MALIGNANT EPITHELIAL TUMOURS OF THE THYROID At present there is unanimous agreement about thè indication and extent of surgery on thè lymph node stations of thè centrai and latero-cervical compartment in malignant epithelial tumours of thè thyroid with regard to medullar tumours; opinions differ, however, when it comes to differentiated papillary and folliculartumours. The lymph nodes are involved in ali malignant epithelial cancers with a different incidence with regard to thè various isotopes. In particular, papillary carcinoma presents an incidence of involvement of thè homolateral lymph nodes of between 30% and 90% and for thè contralateral lymph nodes thè rate is between 19% and 40%; at thè moment of diagnosis lymph node involvement is present in 32%-74.3% of thè centrai lymph nodes and in 70% in those of thè jugular chain; thè incidence of subclinical lymph node metastasis is between 44% and 82%. In follicular carcinoma thè incidence of lymph node metastasis is between 12% and 30%; in medullar tumours it is present in over 50% of cases; in anaplastic carcinoma it is found in 7%-59% of cases. Lymph node involvement regards most frequently thè paratracheal lymph nodes - VI level - homolateral (27%) and contralateral (12%), thè middle jugular and carotid lymph nodes (35%), thè inferior (26%) and supraclavicular nodes (14%) III-IV-V level; thè upper jugular and carotid territory - level II - (17%) is involved in thè presence of a tumour of thè upper area; metastasis of thè lymph node stations of levels I and V is rare. Contralateral lymph node involvement, 292 which is related above ali to thè presence of contralateral metastatic paratracheal adenopathies (12%), regards thè middle (11%), inferior (8%) and upper (6%) levels. Risk factors that favour thè spread of metastasis are thè size of thè tumour, thè histological subtype, locai invasion, biological markers and for AA its multifocal nature. The involvement of lymph node metastasis increases thè risk of locai recurrence and death in patients over 45 years old, especially in thè presence of bilateral metastasis or in thè mediastinic lymph nodes and if thè lymph nodes are fixed or if there has been tumoral invasion through thè capsule. The clinical presence of metastatic adenopathy, besides giving rise to thè suspicion of a thyroid carcinoma which is usually aggressive, is an indication for a diagnostic investigation by ultrasound which can be associated with FNAB and thyroglobulin assay; CT, MRI, scintigraphy are less used. Thyroid surgery offers thè opportunity to observe thè possible presence of metastatic adenopathies in thè centrai compartment - recurrent mediastinic - stressing thè role of thè sentine! lymph node with thè aim of selecting N+ patients and, in thè case of suspicion, thè possibility of carrying out an extemporary histological examination: lymph node involvement is an indication for their removal. With regard to thè surgery of thè lymph node stations in malignant epithelial tumours of thè thyroid, there is stili controversy about thè extent of thè various lymph node levels. The removal of thè centrai area, thè main site of lymphatic drainage for thyroid tumours, was initially carried out in medullar tumours. Today it is also recommended in papillary tumours; only in thè presence of follicular tumours is it not done, unless a metastasis is detected clinically or by radiology. Latero-cervical removal, in thè presence of documented adenopathies detected clinically or radiologically, must consider most of thè levels, and precisely levels II, III, IV, V; we do not recommend prophylactic removal if documented latero-cervical adenopathies are absent. Finally, it should be borne in mind that, even though thè rate of hypothyroidism may increase and, sometimes, expose thè patient to thè risk of trauma to thè inferior laryngeal nerve, thè removal of thè centrai and latero-cervical compartments enables thè surgeon to define thè prognostic factors, to prevent recurrence, to improve thè survival of risk subjects and to avoid further operations. Likewise, it should be stressed that thè associatici! of surgery and radiometabolic ablation at present represents thè radicai treatment of metastatic adenopathy in malignant epithelial tumours of thè thyroid.
Riassunto L'indicazione e l'estensione alla chirurgia delle stazioni linfonodali del compartimento centrale e latero-cervicale nelle neoplasie epiteliali maligne della tiroide trova attualmente consenso unanime nei riguardi dei carcinomi midollari; viceversa, le opinioni sono discordanti nei riguardi dei carcinomi differenziati, papillifero e follicolare. Il coinvolgimento linfonodale riguarda tutte le neoplasie epiteliali maligne con incidenza diversa nei riguardi dei diversi istotipi. In particolare, il carcinoma papillifero presenta una incidenza di interessamento dei linfonodi omolaterali fra 30 - 90% e quello controlaterale tra 19 - 40%; al momento della diagnosi il coinvolgimento linfonodale è presente nel 32% - 74,3% nei linfonodi centrali e nel 70% in quelli della catena giugulare; l'incidenza di metastasi linfonodali subcliniche è compresa tra 44 e 82%. Nel carcinoma follicolare l'incidenza di metastasi linfonodali è compresa tra il 12-30%; nel carcinoma midollare oltre il 50% dei casi; nel carcinoma anaplastico del 7-59% dei casi. L'interessamento linfonodale riguarda più frequentemente i linfonodi paratracheali VI livello - orno (27%) e controlaterali (12%), i linfonodi giugulo-carotidei medi (35%), bassi (26%) e sovra-claveari (14%) 111 - IV - V livello; il territorio giugulo-carotideo superiore livello 11 - (17%) è interessato in presenza di tumore di polo superiore; rara è la presenza di metastasi a carico delle stazioni linfonodali dei livelli I e V. L'interessamento linfonodale contro-laterale, correlato soprattutto alla presenza di adenopatie metastatiche paratracheali (12%) controlaterali riguarda il livello medio (11%), basso (8%), alto (6%). Fattori di rischio che favoriscono la diffusione metastatica sono la dimensione del tumore, il sottotipo istologico, l'invasione locale, i markers biologici e per alcuni AA la multifocalità. L'interessamento di metastasi linfonodali aumenta il rischio di recidiva locale e mortalità nei pazienti di età superiore ai 45 anni, specie in presenza di metastasi bilaterali o nei linfonodi mediastinici e allorché i linfonodi siano fissi o vi sia invasione tumorale attraverso la capsula. La presenza clinica di adenopatia metastatica, oltre a fare sospettare un carcinoma tiroideo per solito aggressivo, pone l'indicazione per un'indagine diagnostica indirizzata verso l'ecografia che può essere associata alla FNAB e al dosaggio della tireoglobulina; meno ricorso viene fatto alla TC, RMN, scintigrafia. La chirurgia tiroidea offre la possibilità di osservare l'eventuale presenza o assenza di adenopatie metastatiche nel compartimento centrale - mediastinico ricorrenziale, sottolineando il ruolo del linfonodo sentinella finalizzato a selezionare i pazienti N+ e, in caso di sospetto, la possibilità di eseguire un esame istologico estemporaneo: l'interessamento linfonodale pone l'indicazione alla esecuzione dello svuotamento. Le vedute riguardanti la chirurgia delle stazioni linfonodali nelle neoplasie epiteliali maligne della tiroide sono tutt'ora discordanti nei riguardi della estensione verso i diversi livelli linfonodali. Lo svuotamento dell'area centrale, principale sito di drenaggio linfatico delle neoplasie tiroidee, prima effettuato nei carcinomi midollari, è oggi raccomandato anche in quelli papillari; solo in presenza di carcinomi follicolari non viene eseguito a meno che non venga evidenziata una metastasi clinica o radiologica. Lo svuotamento latero-cervicale, in presenza di adenopatie documentate, cliniche o radiologiche, deve considerare la maggior parte dei livelli, e precisamente i livelli 11, 111, IV, V; lo svuotamento profilattico non viene da noi suggerito allorché siano assenti adenopatie latero-cervicali documentate. Infine va tenuto presente che, pur aumentando il tasso di ipoparatiroidismo e, l'esposizione al rischio traumatico nei riguardi del nervo laringeo inferiore, lo svuotamento del compartimento centrale e latero-cervicale permette di definire i fattori prognostici, di evitare le recidive, di migliorare la sopravvivenza dei soggetti a rischio e di evitare reinterventi. E' da sottolineare, altresì, che l'associazione della chinirgia e della ablazione radiometabolica rappresenta oggi il trattamento radicale della adenopatia metastatica nelle neoplasie epiteliali maligne della tiroide.
La chirurgia delle stazioni linfonodali nelle neoplasie epiteliali maligne della tiroide. Nodal surgery in malignant epithelial thyroid tumours
FERLITO, Salvatore;
2007-01-01
Abstract
SURGERY OF THE LYMPH NODE STATIONS IN MALIGNANT EPITHELIAL TUMOURS OF THE THYROID At present there is unanimous agreement about thè indication and extent of surgery on thè lymph node stations of thè centrai and latero-cervical compartment in malignant epithelial tumours of thè thyroid with regard to medullar tumours; opinions differ, however, when it comes to differentiated papillary and folliculartumours. The lymph nodes are involved in ali malignant epithelial cancers with a different incidence with regard to thè various isotopes. In particular, papillary carcinoma presents an incidence of involvement of thè homolateral lymph nodes of between 30% and 90% and for thè contralateral lymph nodes thè rate is between 19% and 40%; at thè moment of diagnosis lymph node involvement is present in 32%-74.3% of thè centrai lymph nodes and in 70% in those of thè jugular chain; thè incidence of subclinical lymph node metastasis is between 44% and 82%. In follicular carcinoma thè incidence of lymph node metastasis is between 12% and 30%; in medullar tumours it is present in over 50% of cases; in anaplastic carcinoma it is found in 7%-59% of cases. Lymph node involvement regards most frequently thè paratracheal lymph nodes - VI level - homolateral (27%) and contralateral (12%), thè middle jugular and carotid lymph nodes (35%), thè inferior (26%) and supraclavicular nodes (14%) III-IV-V level; thè upper jugular and carotid territory - level II - (17%) is involved in thè presence of a tumour of thè upper area; metastasis of thè lymph node stations of levels I and V is rare. Contralateral lymph node involvement, 292 which is related above ali to thè presence of contralateral metastatic paratracheal adenopathies (12%), regards thè middle (11%), inferior (8%) and upper (6%) levels. Risk factors that favour thè spread of metastasis are thè size of thè tumour, thè histological subtype, locai invasion, biological markers and for AA its multifocal nature. The involvement of lymph node metastasis increases thè risk of locai recurrence and death in patients over 45 years old, especially in thè presence of bilateral metastasis or in thè mediastinic lymph nodes and if thè lymph nodes are fixed or if there has been tumoral invasion through thè capsule. The clinical presence of metastatic adenopathy, besides giving rise to thè suspicion of a thyroid carcinoma which is usually aggressive, is an indication for a diagnostic investigation by ultrasound which can be associated with FNAB and thyroglobulin assay; CT, MRI, scintigraphy are less used. Thyroid surgery offers thè opportunity to observe thè possible presence of metastatic adenopathies in thè centrai compartment - recurrent mediastinic - stressing thè role of thè sentine! lymph node with thè aim of selecting N+ patients and, in thè case of suspicion, thè possibility of carrying out an extemporary histological examination: lymph node involvement is an indication for their removal. With regard to thè surgery of thè lymph node stations in malignant epithelial tumours of thè thyroid, there is stili controversy about thè extent of thè various lymph node levels. The removal of thè centrai area, thè main site of lymphatic drainage for thyroid tumours, was initially carried out in medullar tumours. Today it is also recommended in papillary tumours; only in thè presence of follicular tumours is it not done, unless a metastasis is detected clinically or by radiology. Latero-cervical removal, in thè presence of documented adenopathies detected clinically or radiologically, must consider most of thè levels, and precisely levels II, III, IV, V; we do not recommend prophylactic removal if documented latero-cervical adenopathies are absent. Finally, it should be borne in mind that, even though thè rate of hypothyroidism may increase and, sometimes, expose thè patient to thè risk of trauma to thè inferior laryngeal nerve, thè removal of thè centrai and latero-cervical compartments enables thè surgeon to define thè prognostic factors, to prevent recurrence, to improve thè survival of risk subjects and to avoid further operations. Likewise, it should be stressed that thè associatici! of surgery and radiometabolic ablation at present represents thè radicai treatment of metastatic adenopathy in malignant epithelial tumours of thè thyroid.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.