Background: The tumor–node–metastasis (TNM) classification system to categorized anaplastic thyroid cancer (ATC) was revised. Methods: The revised system was evaluated using a large database of ATC patients. Results: A total of 757 patients were analyzed. The proportion and median overall survival values (OS: months) for each T category were T1 (n = 8, 1.1%, 12.5), T2 (n = 43, 5.7%, 10.9), T3a (n = 117, 15.5%, 5.7), T3b (n = 438, 57.9%, 3.9), and T4 (n = 151, 19.9%, 5.0). The OS of the N0 and N1 patients were 5.9 and 4.3, respectively (log-rank p < 0.01). Sixty-three (58.3%) patients migrated from stage IV A to IV B by revision based on the existence of nodal involvement and 422 patients (55.7%) were stratified into stage IV B, without a worsening of their OS (6.1), leaving 45 patients (5.9%) in stage IV A with fair OS (15.8). The hazard ratios for the survival of the patients of stage IV B compared to stage IV A increased from 1.1 to 2.1 by the revision. No change was made for stage IV C (n = 290, 38.8%, 2.8). Conclusion: The revised TNM system clearly indicated the prognoses of ATC patients by extracting rare patients with fair prognoses as having stage IV A disease and categorized many heterogeneous patients in stage IV B.

Purposes: To establish the appropriate staging system and assess the role of curative thyroidectomy alone (Surgery) vs. involved-site radiation therapy after open biopsy (OB-ISRT) in stage IE mucosa-associated lymphoid tissue (MALT) lymphoma. Methods: We examined the Tokyo Classification as a modified classification. This retrospective cohort study included 256 patients with thyroid MALT lymphoma; 137 underwent standard therapy (i.e., OB-ISRT) and were enrolled for the Tokyo classification. Sixty stage IE patients with the same diagnosis were examined to compare Surgery with OB-ISRT. Results: Overall survival (p = 0.0092) and relapse-free survival (0.00113) were significantly better in stage IE vs. stage IIE under the Tokyo classification. No OB-ISRT and Surgery patients died, but three OB-ISRT patients relapsed. The incidence of permanent complications was 28% in OB-ISRT (mainly dry mouth) and 0% in Surgery (p = 0.027). The number of painkiller prescription days was significantly greater in OB-ISRT (p < 0.001). During follow-up, the rate of the new appearance/change of the low-density area in the thyroid gland was significantly higher in OB-ISRT (p = 0.031). Conclusions: The Tokyo classification allows an appropriate discrimination between stages IE and IIE MALT lymphoma. Surgery can provide a good prognosis in stage IE cases; it also avoids complications, shortens painful periods during treatment, and simplifies ultrasound follow-up.