Frank Weber

Cabozantinib has significantly improved progression-free survival (PFS) in patients with radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) after lenvatinib and/or sorafenib pretreatment in the phase 3 COSMIC-311 trial, leading to its approval for sequential treatment. Real-world evidence of cabozantinib remains limited, particularly in poorly differentiated thyroid cancer (PDTC). In this retrospective analysis, we included adult patients with RAIR-DTC or PDTC treated with cabozantinib as further-line treatment at the Essen Endocrine Tumor Center (June 2022–July 2025). All patients had received prior targeted therapy and had documented progressive disease at cabozantinib initiation. Best overall response, PFS, overall survival (OS) and adverse events were assessed. Nineteen patients (7 DTC and 12 PDTC) were included in the safety analysis, and 17 patients were included in the efficacy assessment. Under sequential cabozantinib treatment, partial response (PR) was observed in 4/17 (24%): 3/4 in patients switched due to lenvatinib toxicity and 1/13 in those switched due to progression. Median PFS was 5.4 months in DTC and 3.6 months in PDTC. Median OS from cabozantinib initiation was 13.5 months in DTC and 15.8 months in PDTC. Dose reductions or interruptions were required in 6/19 (31.6%), and 3/19 (15.8%) permanently discontinued cabozantinib due to toxicity. In this real-world cohort, further-line cabozantinib showed limited efficacy in RAIR-(P)DTC, especially in PDTC. Responses were more favorable when cabozantinib was initiated due to prior treatment toxicity rather than progression. The substantial toxicity highlights the need for careful management and improved therapeutic strategies in this population.

The efficacy of lenvatinib in treating gastrointestinal neuroendocrine tumors (GI-NETs) has been explored in preclinical studies and early-phase clinical trials, but real-world data remain limited. Data of sixteen patients (median age 65 years; 62.5% female) with advanced and progressive GI-NET who were treated with lenvatinib at the ENETS Center, University Hospital Essen, between July 2019 and February 2024 were analyzed. Patients received all other approved therapies and showed progression within 2 months. Salvage therapy with lenvatinib was initiated after approval from health insurance. Most NETs originated in the small intestine (94%) with a median Ki-67 index of 3.5%. Before lenvatinib, patients received a median of four lines of treatment (range 3–7), including somatostatin analogs (100%), everolimus (100%), chemotherapy (25%) and PRRT (88%). Surgery of the primary and/or metastatic lesions was performed in 81% and ablative therapies in 38%. The median time between NET diagnosis and the initiation of lenvatinib was 100 months. The overall response rate on salvage therapy was 29% and the clinical benefit rate was 100%. The median progression-free survival (PFS) on lenvatinib was 10 months and the median overall survival (OS) after the initiation of lenvatinib reached 113 months. Hypertension was associated with significantly longer PFS (24.5 months, P = 0.007), whereas weight loss correlated with shorter PFS (4 months, P = 0.0032). In this retrospective single-center case analysis, lenvatinib demonstrated promising results in heavily pre-treated and rapidly progressing GI-NET. With an OS of 9.4 years after start of salvage therapy, these results highlight the value of lenvatinib as a therapeutic option for advanced GI-NET patients with otherwise limited treatment alternatives.

Background: Skip metastases, node metastases in the lateral neck sparing the ipsilateral central neck, challenge the current concept of central-to-lateral lymphatic spread. This study sought to delineate patterns of central and lateral neck involvement in unilateral papillary thyroid cancer (PTC) and medullary thyroid cancer (MTC). Methods: This was a retrospective correlative analysis of nodal patterns in surgical specimens from patients with unilateral PTC or MTC who had undergone thyroidectomy with at least ipsilateral central neck dissection between November 1994 and January 2024 at a tertiary referral center. Results: Included were 833 patients with unilateral PTC and 640 patients with unilateral MTC. Simultaneous presence or absence of node metastases was noted in ipsilateral central and lateral neck compartments in 76.6–78.1% of patients with PTC (both node positive in 27.0–54.7% and both node negative in 23.4–49.6%) and 77.3–80.0% of patients with MTC (both node positive in 26.6–33.2% and both node negative in 44.1–53.4%). Only one ipsilateral neck compartment was node positive in 21.9–23.4% of patients with PTC and 20.0–22.7% of patients with MTC. The ipsilateral central, but not the ipsilateral lateral compartment, was node positive in 8.8–16.9% with PTC and 8.6–8.8% of patients with MTC, whereas the ipsilateral lateral, but not the ipsilateral central compartment, was node positive in 6.5–13.1% with PTC and 11.3–14.1% with MTC. Ipsilateral lateral neck involvement sparing the ipsilateral central neck was 1.5–2 times more frequent in patients with node positive MTC than patients with node positive PTC (24.2–25.2% vs. 12.9–17.1%). Greater numbers of node metastases in the ipsilateral central neck compartment were associated with more frequent involvement of the ipsilateral lateral, contralateral central, and contralateral lateral neck compartments. Thyroid tumor diameter intensified nodal spread without changing nodal spread patterns. Conclusions: These histopathological findings, which need to be interpreted in light of the respective tumor biology, offer an unprecedented glimpse at the metastatic patterns of unilateral PTC and MTC. Customizing neck dissection to the patterns of nodal spread, considering operative status (initial vs. reoperative surgery) and experience with neck dissection, may require more frequent concomitant dissections of ipsilateral central and ipsilateral lateral neck compartments.

Zusammenfassung: Das medulläre Schilddrüsenkarzinom (MTC) ist die häufigste das onkologische Outcome bestimmende Manifestation der multiplen endokrinen Neoplasie (MEN) Typ 2. Vor 30 Jahren konnten die Keimbahnmutationen im RET(REarranged-during-Transfection)-Protoonkogen, einem Tumorsuppressorgen auf Chromosom 10q11.2, als Ursache der MEN2 identifiziert und 1993 und 1994 erstveröffentlicht werden. Hieraus entwickelte sich das Konzept der prophylaktischen Thyreoidektomie für asymptomatische Genmutationsträger, das seither Therapiestandard ist. Klinisch-genetische Untersuchungen zeigten hinsichtlich der individuellen Genmutation eine Genotyp-Phänotyp-Korrelation sowohl hinsichtlich der Penetranz und des Entstehungszeitraums des MTC und in geringerem Ausmaß auch hinsichtlich der anderen MEN2-Komponenten Phäochromozytom und primärer Hyperparathyreoidismus. Daraus konnte eine klinisch relevante Risikostratifizierung abgeleitet werden. Die allein genotypbasierte, aber nicht hinreichend genaue Altersempfehlung für den besten Zeitpunkt der prophylaktischen Thyreoidektomie wurde in der Folgezeit durch Kombination des RET-Genotyps mit dem Kalzitoninwert präzisiert, der mutations- und altersunabhängig erst bei Überschreiten des oberen Kalzitoninnormwertes das Risiko einer Lymphknotenmetastasierung anzeigt. Die routinemäßige Kalzitoninbestimmung bei Knotenstrumen, das Familienscreening bei MEN2-Indexpatienten und die karzinompräventive prophylaktische Thyreoidektomie bei normokalzitoninämischen Genmutationsträgern haben dazu geführt, dass heute, 30 Jahre nach der Erstbeschreibung der krankheitsverursachenden Genmutationen, das lebensbedrohende hereditäre MTC heilbar geworden ist: ein leuchtendes Beispiel für den Erfolg translational transnationaler medizinischer Forschung zum Wohl der Betroffenen.

The age-specific development of the three constituent components of multiple endocrine neoplasia type 2 (MEN 2) is incompletely characterized for many of the >30 causative rearranged during transfection (RET) mutations, which this genetic association study aimed to specify. Included in the study were 683 carriers of heterogeneous RET germline mutations: 53 carriers with 1 highest-risk mutation (codon 918); 240 carriers with 8 different high-risk mutations (codon 634); 176 carriers with 16 different intermediate-risk mutations (codon 609, 611, 618, 620, or 630); and 214 carriers with 6 different low-risk mutations (codon 768, 790, 804, or 891).There was a strong genotype-specific development of MEN 2 constituent components, with distinct age gradients from C cell disease to node negative medullary thyroid cancer (MTC), from node negative to node positive MTC, from node positive MTC to pheochromocytoma, and from pheochromocytoma to primary hyperparathyroidism. Primary hyperparathyroidism was not observed among the 53 MEN 2B patients who carried highest-risk mutations (age range: 0.5–50 years), of whom no more than 12 (23%) and 3 (6%) carriers were older than age 30 years and 35 years, respectively. The age-specific development of MTC differed significantly between the four RET risk categories, whereas the age-specific development of pheochromocytoma differed significantly only between the two strongest RET risk categories. No significant differences were noted in the development of primary hyperparathyroidism. These findings delineate age-specific disease manifestation corridors for the three constituent components of MEN 2 by RET genotype. These corridors are useful for initial risk assessment and organ-specific surveillance of newly identified RET carriers going forward.

(1) Background: The wider adoption of a preoperative ultrasound and calcitonin screening complemented by an intraoperative frozen section has increased the number of patients with occult sporadic medullary thyroid cancer (MTC). These advances offer new opportunities to reduce the extent of the initial operations, minimizing operative morbidity and the risk of postoperative thyroxin supplementation without compromising the cure. (2) Methods: This systematic review of the international literature published in the English language provides a comprehensive update on the latest progress made in the risk-adapted surgery for sporadic and hereditary MTC guided by an intraoperative frozen section. (3) Results: The current evidence confirms the viability of a hemithyroidectomy for desmoplasia-negative sporadic MTC. To add an extra safety margin, the hemithyroidectomy may be complemented by a diagnostic ipsilateral central node dissection. Despite the limited extent of the surgery, all the patients with desmoplasia-negative sporadic tumors achieved a biochemical cure with excellent clinical outcomes. A hemithyroidectomy decreases the need for postoperative thyroxine substitution, but a total thyroidectomy may be required for bilateral nodular thyroid disease. Hereditary MTC is a different issue. Because each residual thyroid C cell carries its own risk of malignant progression, a total thyroidectomy remains mandatory for hereditary MTC. (4) Conclusion: In experienced hands, a hemithyroidectomy, which minimizes morbidity without compromising the cure, is an adequate therapy for desmoplasia-negative sporadic MTC.

Thyroid cancer is the only nonreproductive cancer with striking female predominance, although men with thyroid cancer develop more aggressive disease. This study aimed to quantify sex-specific differences in medullary thyroid cancer (MTC) spread after controlling for primary thyroid tumor size. Included in this retrospective analysis were all patients with unilateral solitary MTC who underwent initial neck surgery at a tertiary referral center. A total of 565 patients, 255 men and 310 women, were identified, of whom 467 had sporadic and 98 hereditary MTC. When stratified by sex, and after correction for multiple testing, men had higher preoperative basal calcitonin levels (medians of 655 vs 181 pg/mL; P < 0.001), more frequent extrathyroid extension (25 vs 9%; P < 0.001) and node metastasis (53 vs 27%; P < 0.001) with more involved nodes (medians of 2 vs 0 nodes; P < 0.001) than women but achieved less often biochemical cure (53 vs 74%; P < 0.001). Although absent in patients with very small (≤5 mm) thyroid tumors, sex disparities were immediately apparent in patients with 5.1–40 mm (node metastasis and biochemical cure) and 10.1–40 mm (extrathyroid extension) large thyroid tumors but were lost in patients with thyroid tumors >40 mm as women caught up. Sex disparities were strongest for node metastasis with a 27–41% (overall 24.0%) point difference, followed by biochemical cure with a −15–35% (overall −20.3%) point difference and extrathyroid extension with a 17–24% (14.2% overall) point difference. These findings indicate that the male predominance in MTC aggressiveness is largely biologically driven, warranting further research.