Poorly Differentiated Thyroid Carcinoma Presenting with Gross Extrathyroidal Extension: 1986–2009 Memorial Sloan-Kettering Cancer Center Experience

Abstract

Aggressive surgery in patients with PDTC showing gross ETE resulted in satisfactory locoregional control. Due to the small proportion of patients who received EBRT (22%), it is not possible to analyze its benefit on locoregional control. Of significance is the observation that the majority of patients (60%) who presented with or subsequently developed distant metastases eventually died of distant disease. New systemic therapies to target distant metastatic disease are required for improvements in outcome.

Pediatric Differentiated Thyroid Carcinoma of Follicular Cell Origin: Prognostic Significance of Histologic Subtypes

“…Certain variants of PTC (tall cell, diffuse sclerosing, solid) and poorly differentiated thyroid carcinomas (PDTC) tend to be more aggressive and carry an increased risk of recurrence and mortality, and are therefore classified as high-risk histologies, while classical and follicular variants of PTC carry a more favorable prognosis and are therefore classified as low-risk histologies (4,(15)(16)(17)(18)(19). Given that DTC in children behaves differently from thyroid cancer in adults, it is unclear if histologic subtypes carry the same implications in children as they do in adults.…”

Obatoclax overcomes resistance to cell death in aggressive thyroid carcinomas by countering Bcl2a1 and Mcl1 overexpression

“…Although the vast majority of these tumors is effectively managed by surgical resection followed by radioactive iodine therapy (American Thyroid Association Guidelines Taskforce on Thyroid, et al 2009), a subset of lesions, which includes recurring well differentiated, poorly differentiated, and anaplastic tumors, is refractory to current therapeutic approaches, behaves aggressively, is almost invariably fatal, and thus represents a critical clinical issue (Ibrahimpasic, et al 2013; Siironen, et al 2010). …”

Application of intensity-modulated radiotherapy in unresectable poorly differentiated thyroid carcinoma

“…That study demonstrated the advantage of surgery in PDTC. Ibrahimpasic et al [15] also reported a retrospective study on 27 patients with PDTC presenting with gross extrathyroidal (pT 4a ) extension. All of the patients received aggressive surgery, and 77% of the patients had adjuvant therapy.…”

“…Therefore, the lessons learned from patients with locally advanced, differentiated thyroid carcinoma can probably be applied to those with unresectable PDTC. Unfortunately, the available evidence does not show a strong association between EBRT and locoregional control or prolonged survival in PDTC [4, 6, 15, 19]. …”

“…Surgical resection remains the standard of care, and 131 I therapy is indicated postoperatively if the tumor is radio-avid [3, 4, 6, 13–15]. However, PDTC is an aggressive malignancy with a tendency to invade extensively into adjacent organs, such as the trachea, esophagus, larynx, recurrent laryngeal nerve, prevertebral fascia, blood vessels, soft tissues and muscle.…”