Thyroid. At-A-Glance. Papillary or follicular (differentiated) UNDER 45 YEARS Stage I Any T Any N M0 Stage II Any T Any N M1

Transcription

1 8 Thyroid At-A-Glance S U M M A R Y O F C H A N G E S Tumor staging (T1) has been subdivided into T1a ( 1 cm) and T1b ( 1 2 cm) limited to thyroid The descriptors to subdivide T categories have been changed to solitary tumor (s) and multifocal tumor (m) The terms resectable and unresectable are replaced with moderately advanced and very advanced A N ATO M I C S TAG E / P R O G N O S T I C G R O U P S Separate stage groupings are recommended for papillary or follicular (differentiated), medullary, and anaplastic (undifferentiated) carcinoma Papillary or follicular (differentiated) UNDER 45 YEARS Stage I Any T Any N M0 Stage II Any T Any N M1 ICD-O-3 TOPOGRAPHY CODE C73.9 Thyroid gland ICD-O-3 HISTOLOGY CODE RANGES , , YEARS AND OLDER Stage I T1 N0 M0 Stage II T2 N0 M0 Stage III T3 N0 M0 T1 N1a M0 Stage IVA T4a N0 M0 8 Medullary carcinoma (all age groups) Stage I T1 N0 M0 Stage II T2 N0 M0 T3 N0 M0 Stage III T1 N1a M0 Thyroid 87

2 ANATOMIC STAGE/PROGNOSTIC GROUPS (CONTINUED) Stage IVA T4a N0 M0 Anaplastic carcinoma All anaplastic carcinomas are considered Stage IV Stage IVA T4a Any N M0 INTRODUCTION Although staging for cancers in other head and neck sites is based entirely on the anatomic extent of disease, it is not possible to follow this pattern for the unique group of malignant tumors that arise in the thyroid gland. Both the histologic diagnosis and the age of the patient are of such importance in the behavior and prognosis of thyroid cancer that these factors are included in this staging system. ANATOMY Primary Site. The thyroid gland ordinarily is composed of a right and a left lobe lying adjacent and lateral to the upper trachea and esophagus. An isthmus connects the two lobes, and in some cases a pyramidal lobe is present extending cephalad anterior to the thyroid cartilage. Regional Lymph Nodes. Regional lymph node spread from thyroid cancer is common but of less prognostic significance in patients with well-differentiated tumors (papillary, follicular) than in medullary cancers. The adverse prognostic influence of lymph node metastasis in patients with differentiated carcinomas is observed, only in the older age group. The first echelon of nodal metastasis consists of the paralaryngeal, paratracheal, and prelaryngeal (Delphian) nodes adjacent to the thyroid gland in the central compartment of the neck generally described as Level VI. Metastases secondarily involve the mid- and lower jugular, the supraclavicular, and (much less commonly) the upper deep jugular and spinal accessory lymph nodes. Lymph node metastasis to submandibular and submental lymph nodes is very rare. Upper mediastinal (Level VII) nodal spread occurs frequently both anteriorly and posteriorly. Retropharyngeal nodal metastasis may be seen, usually in the presence of extensive lateral cervical metastasis. Bilateral nodal spread is common. The components of the N category are described as follows: first echelon (central compartment/level VI), or N1a, and lateral cervical and/or superior mediastinal or N1b. The lymph node metastasis should also be described according to the level of the neck that is involved. Nodal metastases from medullary thyroid cancer carry a much more ominous prognosis, although they follow a similar pattern of spread. For pn, histologic examination of a selective neck dissection will ordinarily include six or more lymph nodes, whereas histologic examination of a radical or a modified radical comprehensive neck dissection will ordinarily include ten or more lymph nodes. Negative pathologic evaluation of a lesser number of nodes still mandates a pn0 designation. Metastatic Sites. Distant spread occurs by hematogenous routes for example to lungs and bones but many other sites may be involved. RULES FOR CLASSIFICATION Clinical Staging. The assessment of a thyroid tumor depends on inspection and palpation of the thyroid gland and regional lymph nodes. Indirect laryngoscopy to evaluate vocal cord motion is essential. A variety of imaging procedures can provide additional useful information. These include radioisotope thyroid scans, ultrasonography, computed tomography scans (CT), magnetic resonance imaging (MRI) scans, and PET scans. When cross-sectional imaging is utilized, MRI is recommended so as to avoid contamination of the body with the iodinated contrast medium generally used with CT. Iodinated contrast media make it necessary to delay the postoperative administration of radioactive iodine-131. The diagnosis of thyroid cancer must be confirmed by needle biopsy or open biopsy of the tumor. Further information for clinical staging may be obtained by biopsy 88 American Joint Committee on Cancer 2010

3 of lymph nodes or other areas of suspected local or distant spread. All information available prior to first treatment should be used. Pathologic Staging. Pathologic staging requires the use of all information obtained in the clinical staging, as well as histologic study of the surgically resected specimen. The surgeon s description of gross unresected residual tumor must also be included. DEFINITIONS OF TNM Primary Tumor (T) Note: All categories may be subdivided: (s) solitary tumor and (m) multifocal tumor (the largest determines the classification). TX T0 T1 T1a T1b T2 T3 T4a T4b Primary tumor cannot be assessed No evidence of primary tumor Tumor 2 cm or less in greatest dimension limited to the thyroid Tumor 1 cm or less, limited to the thyroid Tumor more than 1 cm but not more than 2 cm in greatest dimension, limited to the thyroid Tumor more than 2 cm but not more than 4 cm in greatest dimension limited to the thyroid Tumor more than 4 cm in greatest dimension limited to the thyroid or any tumor with minimal extrathyroid extension (e.g., extension to sternothyroid muscle or perithyroid soft tissues) Moderately advanced disease Tumor of any size extending beyond the thyroid capsule to invade subcutaneous soft tissues, larynx, trachea, esophagus, or recurrent laryngeal nerve Very advanced disease Tumor invades prevertebral fascia or encases carotid artery or mediastinal vessels All anaplastic carcinomas are considered T4 tumors T4a Intrathyroidal anaplastic carcinoma T4b Anaplastic carcinoma with gross extrathyroid extension Regional Lymph Nodes (N) Regional lymph nodes are the central compartment, lateral cervical, and upper mediastinal lymph nodes. NX N0 N1 N1a N1b Regional lymph nodes cannot be assessed No regional lymph node metastasis Regional lymph node metastasis Metastasis to Level VI (pretracheal, paratracheal, and prelaryngeal/delphian lymph nodes) Metastasis to unilateral, bilateral, or contralateral cervical (Levels I, II, III, IV, or V) or retropharyngeal or superior mediastinal lymph nodes (Level VII) Distant Metastasis (M) M0 No distant metastasis M1 Distant metastasis A N ATO M I C S TAG E / P R O G N O S T I C G R O U P S Separate stage groupings are recommended for papillary or follicular (differentiated), medullary, and anaplastic (undifferentiated) carcinoma Papillary or follicular (differentiated) UNDER 45 YEARS Stage I Any T Any N M0 Stage II Any T Any N M1 45 YEARS AND OLDER Stage I T1 N0 M0 Stage II T2 N0 M0 Stage III T3 N0 M0 T1 N1a M0 Stage IVA T4a N0 M0 Medullary carcinoma (all age groups) Stage I T1 N0 M0 Stage II T2 N0 M0 T3 N0 M0 Stage III T1 N1a M0 Stage IVA T4a N0 M0 Anaplastic carcinoma All anaplastic carcinomas are considered Stage IV Stage IVA T4a Any N M0 8 Thyroid 89

4 PROGNOSTIC FACTORS (SITE-SPECIFIC FACTORS) (Recommended for Collection) Required for staging None Clinically significant Extrathyroid extension Histology Figures show observed and relative survival rates for patients with papillary adenocarcinoma of the thyroid gland (Figure 8.1A, B), follicular adenocarcinoma of the thyroid gland (Figure 8.2A, B), medullary carcinoma of the thyroid gland (Figure 8.3A, B), and Stage 4 anaplastic carcinoma of the thyroid gland (Figure 8.4A, B). FIGURE 8.2. (A) Five-year, observed survival by combined AJCC stage for follicular adenocarcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) (B) Five-year, relative survival by combined AJCC stage for follicular adenocarcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) HISTOLOGIC GRADE (G) FIGURE 8.1. (A) Five-year, observed survival by combined AJCC stage for papillary adenocarcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) (B) Five-year, relative survival by combined AJCC stage for papillary adenocarcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) 90 Grade is reported in registry systems by the grade value. A two-grade, three-grade, or four-grade system may be used. If a grading system is not specified, generally the following system is used: GX G1 G2 G3 G4 Grade cannot be assessed Well differentiated Moderately differentiated Poorly differentiated Undifferentiated American Joint Committee on Cancer 2010

5 FIGURE 8.4. (A) Five-year, observed survival by combined FIGURE 8.3. (A) Five-year, observed survival by combined AJCC stage for medullary carcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) (B) Five-year, relative survival by combined AJCC stage for medullary carcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) HISTOPATHOLOGIC TYPE There are four major histopathologic types*: Papillary carcinoma (including follicular variant of papillary carcinoma) Follicular carcinoma (including Hurthle cell carcinoma) Medullary carcinoma Undifferentiated (anaplastic) carcinoma *At present, more aggressive variants of differentiated carcinomas like tall cell variant of papillary carcinoma and insular carcinoma are grouped under differentiated carcinoma. BIBLIOGRAPHY Ain KB. Papillary thyroid carcinoma: etiology, assessment, and therapy. Endocrinol Metab Clin North Am. 1995;24: Thyroid AJCC stage for Stage 4 anaplastic carcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) (B) Five-year, relative survival by combined AJCC stage for Stage 4 anaplastic carcinoma of the thyroid gland, (95% confidence intervals correspond to year-5 survival rates.) 8 Andersen PE, Kinsella J, Loree TR, Shaha AR, Shah JP. Differentiated carcinoma of the thyroid with extrathyroid extension risks for failure and patterns of recurrence. Am J Surg. 1995;170: Antonacci A, Brierley G, Bacchi F, Consorti C, et al. Thyroid cancer. In: Hermanek P, Gospodarowicz MK, Henson DE, et al., editors. Prognostic factors in cancer. Berlin: Springer; p Baloch ZW, LiVolsi VA. Prognostic factors in well-differentiated follicular-derived carcinoma and medullary thyroid carcinoma. Thyroid. 2001;11(7): Brierley JD, Asa SL. Thyroid cancer. In: Gospodarowicz MK, O Sullivan B, Sobin LH, editors. Prognostic factors in cancer. Hoboken, NJ: Wiley; Brierley J, Tsang R, Simpson WJ, et al. Medullary thyroid cancer analyses of survival and prognostic factors and the role of radiation therapy in local control. Thyroid. 1996;6: Brierley JD, Panzarella T, Tsang RW, et al. Comparing staging classifications using thyroid cancer as an example. Cancer. 1997;79:

6 Brierley J, Tsang R, Panzarella T, Bana N. Prognostic factors and the effect of treatment with radioactive iodine and external beam radiation on patients with differentiated thyroid cancer seen at a single institution over 40 years. Clin Endocrinol (Oxford). 2005;63(4): Cady B, Rossi R, Silverman M, et al. Further evidence of the validity of risk group definition in differentiated thyroid carcinoma. Surgery. 1985;98: Cohn K, Blackdahl M, Forsslund G, et al. Prog nostic value of nuclear DNA content in papillary thyroid carcinoma. World J Surg. 1984;8: Goutsouliak V, Hay JH. Anaplastic thyroid cancer in British Columbia : a population-based study. Clin Oncol (R Coll Radiol). 2005;17(2):75 8. Hay ID, Grant CS, Taylor WF, et al. Ipsilateral lobectomy versus bilateral lobar resection in papillary thyroid carcinoma: a retrospective analysis of surgical outcome using a novel prognostic scoring system. Surgery. 1987;102: Hay ID, McConahey WM, Goellner JR. Managing patients with papillary thyroid carcinoma: insights gained from the Mayo Clinic s experience of treating 2,512 consecutive patients during 1940 through Trans Am Clin Climatol Assoc. 2002a;113: Hay ID, Thompson GB, Grant CS, et al. Papillary thyroid carcinoma managed at the Mayo Clinic during six decades ( ): temporal trends in initial therapy and long-term outcome in 2,444 consecutively treated patients. World J Surg. 2002b;26(8): Hedinger C. Histological typing of thyroid tumours: WHO international histological classification of tumours. 2nd ed. Berlin: Springer; Hundahl SA, Cady B, Cunningham MP, et al. (United States and German Thyroid Cancer Study Group): initial results from a prospective cohort of 5, 583 cases of thyroid carcinoma treated in the United States during Cancer. 2000;89: Ito Y, Tomoda C, Uruno T, et al. Prognostic significance of extrathyroid extension of papillary thyroid carcinoma: massive but not minimal extension affects the relapse-free survival. World J Surg. 2006;30(5): LiVolsi VA. Surgical pathology of the thyroid. Philadelphia, PA: WB Saunders; Mazzaferri EL, Jhiang S. Long-term impact of initial surgical and medical therapy on papillary and follicular thyroid cancer. Am J Med. 1994;97: McConahey WM, Hay ID, Woolner LB, et al. Papillary thyroid cancer treated at the Mayo Clinic : initial manifestations, pathological findings, therapy and outcome. Mayo Clinic Proc. 1986;61: McIver B, Hay ID, Giuffrida DF, Dvorak CE, Grant CS, Thompson GB, et al. Anaplastic thyroid carcinoma: a 50-year experience at a single institution. Surgery. 2001;130(6): Randolph GW, Maniar D. Medullary carcinoma of the thyroid. Cancer Control. 2000;7(3): Rosai J, Carcangiu L, DeLellis RA. Tumors of the thyroid gland, 3rd series. Washington, DC: Armed Forces Institute of Pathology; Rossi R. Prognosis of undifferentiated carcinoma and lymphoma of the thyroid. Am J Surg. 1978;135: Saad MF, Ordonez NG, Rashid RK, et al. Medullary carcinoma of the thyroid: a study of the clinical features and prognostic factors in 161 patients. Medicine. 1984;63: Shah JP, Loree TR, Dharker D, et al. Prognostic factors in differentiated carcinoma of the thyroid gland. Am J Surg. 1992;1645: Shaha AR. Implications of prognostic factors and risk groups in the management of differentiated thyroid cancer. Laryngoscope. 2004;114(3): Shaha AR. TNM classification of thyroid carcinoma. World J Surg. 2007;31(5): Shaha AR, Loree TR, Shah JP. Prognostic factors and risk group analysis in follicular carcinoma of the thyroid. Surgery. 1995;118: Shaha AR, Shah JP, Loree TR. Risk group stratification and prognostic factors in papillary carcinoma of the thyroid. Ann Surg Oncol. 1996;3: Shoup M, Stojadinovic A, Nissan A, Ghossein RA, Freedman S, Brennan MF, et al. Prognostic indicators of outcomes in patients with distant metastases from differentiated thyroid carcinoma. J Am Coll Surg. 2003;197(2): Simpson WL, Panzarella T, Carruthers JS, et al. Papillary and follicular thyroid cancer: impact of treatment in 1, 578 patients. Int J Radiat Oncol Biol Phys. 1988;14: Young RL, Mazzaferri EL, Rahea J, et al. Pure follicular thyroid carcinoma: impact of therapy in 214 patients. J Nucl Med. 1980;21: American Joint Committee on Cancer 2010

7 T HYROID STAGING FORM CLINICAL Extent of disease before any treatment y clinical staging completed after neoadjuvant therapy but before subsequent surgery TX T0 T1 T1a T1b T2 T3 T4a T4b T4a T4b TUMOR SIZE: STAGE CATEGORY DEFINITIONS PRIMARY TUMOR (T) All categories may be subdivided: (s) solitary tumor and (m) multifocal tumor (the largest determines the classification). Primary tumor cannot be assessed No evidence of primary tumor Tumor 2 cm or less in greatest dimension limited to the thyroid Tumor 1 cm or less, limited to the thyroid Tumor more than 1 cm but not more than 2 cm in greatest dimension, limited to the thyroid Tumor more than 2 cm but not more than 4 cm in greatest dimension, limited to the thyroid Tumor more than 4 cm in greatest dimension limited to the thyroid, or any tumor with minimal extrathyroid extension (e.g., extension to sternothyroid muscle or perithyroid soft tissues) Moderately advanced disease. Tumor of any size extending beyond the thyroid capsule to invade subcutaneous soft tissues, larynx, trachea, esophagus, or recurrent laryngeal nerve Very advanced disease. Tumor invades prevertebral fascia or encases carotid artery or mediastinal vessels All anaplastic carcinomas are considered T4 tumors Intrathyroidal anaplastic carcinoma Anaplastic carcinoma with gross extrathyroid extension LATERALITY: left right bilateral PATHOLOGIC Extent of disease through completion of definitive surgery y pathologic staging completed after neoadjuvant therapy AND subsequent surgery TX T0 T1 T1a T1b T2 T3 T4a T4b T4a T4b NX N0 N1 N1a N1b M0 M1 REGIONAL LYMPH NODES (N) Regional lymph nodes are the central compartment, lateral cervical, and upper mediastinal lymph nodes. Regional lymph nodes cannot be assessed. No regional lymph node metastasis Regional lymph node metastasis Metastasis to Level VI (pretracheal, paratracheal, and prelaryngeal/delphian lymph nodes) Metastasis to unilateral, bilateral, or contralateral cervical (Levels I, II, III, IV or V) or retropharyngeal or superior mediastinal lymph nodes (Level VII) DISTANT METASTASIS (M) No distant metastasis (no pathologic M0; use clinical M to complete stage group) Distant metastasis NX N0 N1 N1a N1b M1 HOSPITAL NAME/ADDRESS PATIENT NAME/INFORMATION (continued on next page) Thyroid 93

8 T HYROID STAGING FORM CLINICAL Separate stage groupings are recommended for papillary or follicular (differentiated), medullary, and anaplastic (undifferentiated) carcinoma. Papillary or Follicular (Differentiated) UNDER 45 YEARS I Any T Any N M0 II Any T Any N M1 Papillary or Follicular (Differentiated) 45 YEARS AND OLDER I T1 N0 M0 II T2 N0 M0 III T3 N0 M0 T1 N1a M0 IVA T4a N0 M0 Medullary Carcinoma (All age groups) I T1 N0 M0 II T2 N0 M0 T3 N0 M0 III T1 N1a M0 IVA T4a N0 M0 Anaplastic Carcinoma All anaplastic carcinomas are considered Stage IV IVA T4a Any N M0 Stage unknown A NATOMIC S TAGE P ROGNOSTIC G ROUPS PATHOLOGIC Separate stage groupings are recommended for papillary or follicular (differentiated), medullary, and anaplastic (undifferentiated) carcinoma. Papillary or Follicular (Differentiated) UNDER 45 YEARS I Any T Any N M0 II Any T Any N M1 Papillary or Follicular (Differentiated) 45 YEARS AND OLDER I T1 N0 M0 II T2 N0 M0 III T3 N0 M0 T1 N1a M0 IVA T4a N0 M0 Medullary Carcinoma (All age groups) I T1 N0 M0 II T2 N0 M0 T3 N0 M0 III T1 N1a M0 IVA T4a N0 M0 Anaplastic Carcinoma All anaplastic carcinomas are considered Stage IV IVA T4a Any N M0 Stage unknown HOSPITAL NAME/ADDRESS PATIENT NAME/INFORMATION (continued from previous page) 94 American Joint Committee on Cancer 2010

9 T HYROID STAGING FORM PROGNOSTIC FACTORS (SITE-SPECIFIC FACTORS) REQUIRED FOR STAGING: None CLINICALLY SIGNIFICANT: Solitary or Multifocal tumors in the primary site Histologic Grade (G) (also known as overall grade) Grading system 2 grade system Grade Grade I or 1 3 grade system Grade II or 2 4 grade system Grade III or 3 No 2, 3, or 4 grade system is available Grade IV or 4 ADDITIONAL DESCRIPTORS Lymphatic Vessel Invasion (L) and Venous Invasion (V) have been combined into Lymph-Vascular Invasion (LVI) for collection by cancer registrars. The College of American Pathologists (CAP) Checklist should be used as the primary source. Other sources may be used in the absence of a Checklist. Priority is given to positive results. Lymph-Vascular Invasion Not Present (absent)/not Identified Lymph-Vascular Invasion Present/Identified Not Applicable Unknown/Indeterminate Residual Tumor (R) The absence or presence of residual tumor after treatment. In some cases treated with surgery and/or with neoadjuvant therapy there will be residual tumor at the primary site after treatment because of incomplete resection or local and regional disease that extends beyond the limit of ability of resection. RX Presence of residual tumor cannot be assessed R0 No residual tumor R1 Microscopic residual tumor R2 Macroscopic residual tumor General Notes : For identification of special cases of TNM or ptnm classifications, the "m" suffix and "y," "r," and "a" prefixes are used. Although they do not affect the stage grouping, they indicate cases needing separate analysis. m suffix indicates the presence of multiple primary tumors in a single site and is recorded in parentheses: pt(m)nm. y prefix indicates those cases in which classification is performed during or following initial multimodality therapy. The ctnm or ptnm category is identified by a "y" prefix. The yctnm or yptnm categorizes the extent of tumor actually present at the time of that examination. The "y" categorization is not an estimate of tumor prior to multimodality therapy. r prefix indicates a recurrent tumor when staged after a disease-free interval, and is identified by the "r" prefix: rtnm. a prefix designates the stage determined at autopsy: atnm. surgical margins is data field recorded by registrars describing the surgical margins of the resected primary site specimen as determined only by the pathology report. neoadjuvant treatment is radiation therapy or systemic therapy (consisting of chemotherapy, hormone therapy, or immunotherapy) administered prior to a definitive surgical procedure. If the surgical procedure is not performed, the administered therapy no longer meets the definition of neoadjuvant therapy. Clinical stage was used in treatment planning (describe): National guidelines were used in treatment planning NCCN Other (describe): Physician signature Date/Time HOSPITAL NAME/ADDRESS PATIENT NAME/INFORMATION (continued on next page) Thyroid 95

10 T HYROID STAGING FORM Illustration Indicate on diagram primary tumor and regional nodes involved. HOSPITAL NAME/ADDRESS PATIENT NAME/INFORMATION (continued from previous page) 96 American Joint Committee on Cancer 2010