Difficult thyroid cancer cases

Ampica Mangklabruks MD10 May 2012

Case 1 : A 50 year-old -man• Diagnosed as papillary thyroid carcinoma since yr

2000• Near total thyroidectomy in yr 2000, cervical Lymph

node positive for metastasis . (with surgical complications: Hypoparathyroidism and TVC paralysis)

• Received radioactive iodine complete ablation• Bilateral lung metastasis was detected by WBS in yr

2005• Plain Chest film- negative• CT chest : not done

Case 1 ; Pre treatment WBS

Pulmonary metastases (1)

Key criteria for theraputic decision– Size of metastatic lesion• Macronodular detected by chest x-ray• Micronodular detected by chest CT• lesions can not detect by CT (only WBS positive)

– Avidity of RAI– Stability of metastatic lesion– Pulmonary fibrosis from radiation pneumonitis

(rare)

Pulmonary metastases (2)

• Pulmonary micrometastases treated with RAI (Rec gr A) highest rate of complete remission

• May use empiric dose (100-200mCi) or dosimetry• Macronodular met use RAI if iodine avid (continue if

benefit can be demonstated ie size reduction, Tg decreased ) but complete remission is not common.

• Non-RAI –avid pulmonary metastases :– Micronodular : RAI and post treatment scan– Macronodular : RAI usually no benefit, consider

chemotherapy , Tyrosine Kinase Inhibitor ,palliative treatment

Case 1

• He received RAI, 150 mCi each times , for 6-7 times (every 6-12 months)

• total dose of I131 = 1000 millicurie• In June 2010: WBS still show residual bilat

lung metastasis• Thyroglobulin= 18.6, anti TG= 269

Dose and methods of administering I131 for locoregional or metastatic disease

• The optimal therapeutic dose is uncertain and controversial– Three approach• Empiric fixed dose• Therapy determined by body and blood dosimetry (upper

limit)• Quantitative tumor dosimetry

– No study to compare the outcom available– Dosimetry usually reserved for pt with distant

metastasis, renal insufficiency

Long term complications of RAI

• Salivary gland damage, dental caries, nasolacrimal duct obstruction.

• Secondary malignancies and leukemia ( increased risk at accumulative dose 500-600 mCi)

Case 1

• Internal dosimetry : rapid washout• Received lithium carbonate (300) , monitoring

blood level (blood level after receiving 900mg/d =0.82 (0.6-1.2 mmol/L)

• Repeat dosimetry : delayed wash out• Total dose of RAI not exceed safty dose at lung

and marrow. • Repeat I131 150 millicurie with lithium (Feb

2011)

Lithium and thyroid cancer • Action : inhibit thyroid hormone release without

impairing iodine uptakeEnhance I131 retention in normal thyroid and tumor cell

• Koong SS et al : lithium can increase estimate I131 radiation dose in metastatic tumor by 2 fold (tumor which rapidly clear iodine)

• Liu YY et al can not demonstrate clinical benefit (12 pt)• ATA recommendation : Data insufficient to recommend

lithium therapy ( rating I)

• Post treatment scan : good uptake at both lung

• Follow up WBS september 2011 : complete I131 ablation

• Thyroglobulin levelDate June 2010 (off T4)

September 2011 (off T4)

March 2012 (off T4)

Thyroglobulin 18.6 10.5 2.8

Anti-thyroglobulin

265.1 82.8 31.3

Case 1

Case 1 ; Post treatment WBS

Case 1 : remission

Case 2: a 49-year-old woman

• A history of thyroid nodule for 30 years, getting bigger last 5 years.

• I yr ago: Rt shoulder pain , mass found at scalp. Difficulty in breathing. No hoarseness, no difficulty in swallowing.

• Physical Exam: thyroid nodule 10 cm diameter, scalp nodule 5 cm, swelling mass Rt upper arm.

• FNA at scalp : Metastasis follicular carcinoma• FNA thyroid nodule: Follicular neoplasm

• Rt humerus :Plain film : osteolytic lesion Rt proximal humerus, Impending pathological fracture

CT results

• Lt Thyroid mass 6.6x8.1x10.8cms.Rightward displacement of trachea and esophagus. Posterior displacement of carotid artery.Part of mass can not be separates from trachea, esophagus, and carotid artery.

• Skull metas right high parietal bone.• Bone scan; multiple bone met at skull, rt

humerous, ipsilateral distal clavicle, rt scapula and Lt pubic bone

Treatment of bone metastases

• Key criteria for therapeutic decision:– Presence of or risk of pathologic fracture,

particularly in weight bearing structure– Risk of neurological compromise from vertebral

lesions– Presence of pain– Avidity of RAI uptake– Potential significant marrow exposure from

radiation (RAI- avid pelvic metastases)

Treatment of bone metastases

• Complete surgical resection for isolate lesion• RAI therapy improve survival (but rarely curative)• External radiation for lesion with severe pain,

fracture, neurological complication external radiation and glucocorticoid.

• Others such as intra-arterial embolization, radiofrequency ablation, periodic pamidronate or zoledronate infusion.etc

How to manage this patient??

• RAI ?? : Need thyroidectomy first• Thyroidectomy?? Possible??• Palliative??• Rt humerous : Intralesional curette and

prophylactic fixation