CYSTIC PAPILLARY THYROID CARCINOMA METASTASIS TO CERVICAL LYMPH NODES

 

Case provided by Amy Stein, MD

Case History

The patient is a 36 year old man who noted a palpable mass on the right side of his neck.  During his office visit, a fine needle aspiration of the mass was performed and in the clinical history, the clinician questioned whether the specimen was a cyst or a lymph node.  Subsequently, the patient underwent excision of the mass without any preceding radiologic studies.  At surgery, the mass was identified deep to the right external jugular vein and anterior to the sternocleidomastoid muscle.  There were smaller lymph nodes inferior to the mass which were included in the surgical specimen. 

 Microscopic Findings

The fine needle aspiration was processed using the SurePath liquid-based preparation to create a thin-layer slide.   The slide shows occasional sheets and papillary clusters of follicular cells with mild nuclear enlargement and rare intranuclear pseudoinclusions in a background of abundant blood and numerous hemosiderin-laden macrophages.   Some of the clusters have central calcifications with concentric layering consistent with psammoma bodies.  The surgical specimen showed tan soft tissue measuring up to 2.7 cm which contained multiple smooth walled cystic structures containing watery brown fluid measuring up to 1.8 cm.  Upon microscopic examination, there are three lymph nodes, the largest of which shows multiple large cystic foci containing hemosiderin-laden macrophages, several of which have foci of papillary carcinoma protruding into the cystic spaces.  There is also a prominent fibrotic focus between the cystic areas that shows papillary carcinoma.  The carcinoma has a papillary architecture with crowded follicular cells lining the papillary fronds.   The nuclei have pale nuclear chromatin (“Orphan Annie Eye” appearance), scattered nuclear grooves, and rare intranuclear pseudoinclusions.  There are numerous concentrically laminated calcified psammoma bodies present both within papillary stalks and in clusters within the lymph node.  The two additional lymph nodes show micrometastatic papillary carcinoma.

Diagnosis

CYSTIC PAPILLARY THYROID CARCINOMA METASTASIS TO CERVICAL LYMPH NODES

Discussion

Papillary carcinoma is the most common type of thyroid carcinoma and is increasing in incidence in the United States.  The increased frequency is in part due to better detection of small cancers with the use of ultrasound.  However, there have also been significant increases in cancers larger than 5 cm as well as higher rates of local and distant metastases.   Papillary carcinoma peaks in the fifth decade and predominates in women with a female: male ratio of 3:1.  Cystic change is common in papillary carcinoma, however, it is only marked in approximately 10% of tumors.  Lymph node metastases may also show cystic change with prominent cystic changes occurring in roughly 25% of lymph node metastases.  Landry, CS, et al.6 found that the 93% of lateral neck lymph nodes which are cystic on ultrasound examination are due to cystic papillary thyroid carcinoma metastases.  Patients with papillary carcinoma present with local lymph node and distant metastases in 30-50% and 2-5% of cases respectively.  Age is an important prognostic variable and patients diagnosed with carcinoma between 20 and 45 years old have the best prognosis.  A study by Zaydfudim, et al. 4 using the Surveillance, Epidemiology, and End Results registry (SEER) 1998 to 2003 database showed that lymph node metastasis of papillary carcinoma had no adverse prognostic impact on patients younger than 45 years old.  On the other hand, patients 45 years old and older had a 46% increased risk of death when papillary carcinoma involved lymph nodes.

The patient is scheduled for a follow-up appointment in one week to discuss additional surgical therapy including likely total thyroidectomy with regional neck dissection and possible medical therapy.

 

 References

1.      Nikiforov, YE.  Diagnostic Pathology and Molecular Genetics of the Thyroid.  Philadelphia:  Lippincott Williams & Wilkins, 2009:  160-207.

2.     Tuttle, RM.  “Overview of papillary thyroid cancer.” UpToDate 2011; 1-17.

3.     Ross, DS.  “Cystic thyroid nodules.” UpToDate 2011; 1-8.

4.     Zaydfudim, V, et al.  “The impact of lymph node involvement on survival in patients with papillary and follicular thyroid carcinoma.”  Surgery 2008; 144: 1070-1077.

5.     Tuttle, RM. “Overview of the management of differentiated thyroid cancer.” UpToDate 2011; 1-21.

6.     Landry, CS, et al.  “Cystic lymph nodes in the lateral neck as indicators of metastatic papillary thyroid cancer.”  Endocrine Practice 2011; 17 (2): 240-244.

 

SurePath™ slide; Low power magnification: sheets of follicular cells
SurePath™ slide; High power magnification:  Hemosiderin-laden macrophages consistent with cystic contents.
SurePath™ slide; Low power magnification: Papillary cluster of follicular cells
SurePath™ slide; High power magnification: Papillary cluster of follicular cells containing concentrically layered calcification consistent with a psammoma body
SurePath™ slide; High power magnification: Enlarged follicular cells with rare intranuclear pseudoinclusions
 Lymph node, H & E stain; Low power magnification: Cystic spaces lined by papillary carcinoma
 Lymph node, H & E stain; Low power magnification: Cystic space lined by papillary carcinoma
Lymph node, H & E stain; Medium power magnification:  Cystic space containing papillary fronds of papillary carcinoma
Lymph node, H & E stain; Medium power magnification:  Papillary architecture of papillary carcinoma
 Lymph node, H & E stain; High power magnification:  Nuclei with pale nuclear chromatin ("Orphan Annie Eye" appearance)
 Lymph node, H & E stain; Low power magnification:  Right lower portion of slide shows papillary architecture of papillary carcinoma.  Left upper portion of field shows hemosiderin-laden macrophages within the cystic space.
Lymph node, H & E stain; Low power magnification:  Right portion of slide shows papillary fronds of papillary carcinoma.  Left portion of field shows blood and hemosiderin-laden macrophages within the cystic space.
Lymph node, H & E stain; Medium power magnification:  Papillary frond containing a calcification with concentric layering consistent with a psammoma body.
  Lymph node, H & E stain; High power magnification:  Concentrically laminated psammoma body
 Lymph node, H & E stain; Low power magnification:  Papillary carcinoma
 Lymph node, H & E stain; Low power magnification:  Papillary carcinoma with numerous psammoma bodies
 Lymph node, H & E stain; High power magnification:  Nuclei with pale nuclear chromatin ("Orphan Annie Eye" appearance)
 Lymph node, H & E stain; High power magnification:  Psammoma body within papillary carcinoma
 Lymph node, H & E stain; High power magnification:  Nuclei with pale nuclear chromatin ("Orphan Annie Eye" appearance)
 Lymph node, H & E stain; High power magnification:  Papillary carcinoma with an intranuclear pseudoinclusion
Lymph node, H & E stain; High power magnification:  Papillary carcinoma with rare  intranuclear pseudoinclusions
 Lymph node, H & E stain; Low power magnification:  Small lymph node with micrometastatic papillary carcinoma
 Lymph node, H & E stain; Medium power magnification:  Fibrotic focus within papillary carcinoma containing a cluster of numerous psammoma bodies
 Lymph node, H & E stain; Medium power magnification:  Papillary carcinoma
 Lymph node, H & E stain; Medium power magnification:  Papillary carcinoma