Patterns of Failure in Anaplastic Thyroid Cancer Patients

Program: Abstracts - Orals, Poster Previews, and Posters
Session: SAT 270-310-Thyroid Neoplasia (posters)
Clinical/Translational
Saturday, April 2, 2016: 1:15 PM-3:15 PM
Exhibit/Poster Hall (BCEC)

Poster Board SAT 309
Sarika N Rao*, Naifa L Busaidy, Ramona Dadu, Kenneth Hess, Mark Zafereo, William William, Stephen Lai, Vlad Sandulache, Brandon Gunn, Charles Lu and Maria E Cabanillas
The University of Texas MD Anderson Cancer Center, Houston, TX
Background

Anaplastic thyroid cancer (ATC) is one of the most lethal forms of cancer. The accepted practice is surgery followed by external beam radiation therapy (RT) preferably with radiosensitizing chemotherapy (chemoRT) for curative intent in stage IVA patients (pts). For higher stage disease, initial treatment (tx) consists of palliative chemoRT. We reviewed our most recent data to describe the outcomes of the current therapeutic strategies. 

Methods

Between 1/2013-9/2015, 64 new pts were seen at our institution for ATC. We excluded the following pts: 6 due to rapid progression of disease who never received tx, 6 who were seen one time and lost to follow up, and 2 with microfocal ATC. Of the remaining 50 pts, all received one or more of the known tx: surgery and/or chemoRT. Median overall survival (OS) and time to failure (TTF) were calculated by the Kaplan Meier method. TTF was defined as the first time to locoregional or distant progression and/or new distant disease. 

Results

Median age at diagnosis was 63 years and 26/50 (52%) were women. 11/50 (22%) were stage IVA, 11/50 (22%) IVB, and 28/50 (56%) IVC. Lung was the most common site of metastatic disease, followed by bone and brain. 50 gene mutation testing was performed in 43/50 (86%) pts. 100% of IVA pts had surgery followed by chemoRT (primarily consisting of taxanes and platinums). 8/11 IVB pts received chemoRT and 1 received a tyrosine kinase inhibitor (TKI). 21/28 IVC pts received chemoRT, 2 received cytotoxic chemotherapy (chemo), and 3 received RT. 10/11 IVB and 18/28 IVC pts had R0-R2 surgery elsewhere prior to their treatment at our institution or because the diagnosis of ATC was not known at the time of resection. 8/11 IVA, 6/11 IVB, and 13/28 IVC received additional chemo (cytotoxic chemo, TKI, or immunotherapy) after completion of first-line tx. Median OS for all pts was 10.3 months. 41% were alive at 1 year. Median OS has not been reached in IVA pts, however median OS in IVB and IVC was 11.5 and 5 months, respectively. Median TTF after first tx was 3.9 months in the entire cohort. Median TTF in IVA, IVB, and IVC pts was 7, 4.2, and 3.8 months, respectively. Median time to locoregional failure in IVA pts was not reached. The median time to locoregional failure in IVB and IVC was 6 and 7 months, respectively. Male gender negatively impacted survival, with hazard ratio of 2.4 (p =0.048).  No differences were noted based on tumor size (5 cm cutoff), age (60 years cutoff), BRAF, and p53 mutations. However, a trend of (+) p53 on TTF, HR 1.8 (0.9-3.5), p=0.12, was observed.

Conclusion

Pts with stage IVA disease benefit from the current standard of care: surgery plus chemoRT. In this cohort, stage IVB and IVC pts have an unacceptably low TTF with the current regimens. Therefore, better treatment strategies, including adjuvant and/or neoadjuvant chemo, should be studied in IVB and IVC ATC pts.

Nothing to Disclose: SNR, NLB, RD, KH, MZ, WW, SL, VS, BG, CL, MEC

*Please take note of The Endocrine Society's News Embargo Policy at https://www.endocrine.org/news-room/endo-annual-meeting/pr-resources-for-endo