Thoracic metastasectomy for thyroid malignancies

Management of patients with extensive locally advanced thyroid cancer: results of multimodal treatments

PURPOSE

Surgery plays a key role in the treatment of thyroid cancer (TC) patients. Locally advanced cases, however, can require an extensive surgical approach with technical issues and a high risk of complications. In these cases, a multidisciplinary evaluation should be carried out to evaluate pros and cons. The aim of this study was to share our experience, as a multidisciplinary team, in the management of patients with locally advanced TC with a particularly extensive local disease, whose surgical approach could be challenging and part of a multimodal treatment.

METHODS

We retrospectively evaluated clinical, surgical, and oncologic features of all patients with locally advanced TC who had undergone multidisciplinary surgery from January 2019 to June 2020.

RESULTS

Six patients (two cases each of poorly differentiated, papillary, and medullary TC) were included. Four out of six were suffering from symptoms related to the advanced disease. At pre-surgical evaluation, a multidisciplinary team proposed extended surgery with radical intent via cervicotomy and sternotomy, considering other therapies not feasible or probably ineffective without it. No one passed away in intra- or perioperative time. At the end of follow-up (median 2.6 years), all patients presented a remission of symptoms due to the advanced disease, four patients were submitted to adjuvant therapies and only one patient died for a cause unrelated to the disease.

CONCLUSION

This series of very advanced TCs shows the effectiveness of a surgery performed by a multidisciplinary team in controlling symptoms, allowing adjuvant therapies, and improving the survival of patients whose cases would otherwise be very difficult to manage.

Prognostic Outcome of Pulmonary Resection for Pulmonary Metastases from Gastric Cancer

PURPOSE

Regardless of the devastating outcomes of pulmonary resection for metastases from gastric cancer, a handful of patients survive long after pulmonary metastasectomy. This study aimed to identify a good candidate for pulmonary resection for metastases from gastric cancer.

METHODS

Between 2005 and 2023, 564 patients underwent pulmonary metastasectomy in our department, of which 12 patients underwent pulmonary resection for metastases from gastric cancer. Variables evaluated were the number and size of metastatic lesions, surgical procedure, disease-free interval (DFI), and the serum carcinoembryonic antigen at pulmonary metastasectomy.

RESULTS

The DFI following gastrectomy ≤12.5 months group had a significantly worse overall survival (OS) than the other group (p = 0.005). A comparison between DFI following gastrectomy ≤12.5 months group and DFI following gastrectomy >12.5 months group showed a significant difference in serum carcinoembryonic antigen (CEA) value at pulmonary metastasectomy (p = 0.048). The serum CEA value at pulmonary metastasectomy >5.8 ng/ml group had a significantly worse OS than the other group (p = 0.001).

CONCLUSION

Pulmonary metastasectomy can be indicated in some patients with metastasis from gastric cancer who have longer DFI from gastrectomy and lower serum CEA at pulmonary metastasectomy.

State of the art and future directions in the systemic treatment of medullary thyroid cancer

PURPOSE OF REVIEW

Systemic treatment is the only therapeutic option for patients with progressive, metastatic medullary thyroid cancer (MTC). Since the discovery of the rearranged during transfection (RET) proto-oncogene (100% hereditary, 60-90% sporadic MTC), research has focused on finding effective systemic therapies to target this mutation. This review surveys recent findings.

RECENT FINDINGS

Multikinase inhibitors are systemic agents targeting angiogenesis, inhibiting growth of tumor cells and cells in the tumor environment and healthy endothelium. In the phase III EXAM and ZETA trials, cabozantinib and vandetanib showed progression-free survival benefit, without evidence of prolonged overall survival. Selpercatinib and pralsetinib are kinase inhibitors with high specificity for RET; phase I and II studies showed overall response rates of 73% and 71% in first line, and 69% and 60% in second line treatment, respectively. Although resistance mechanisms to mutation-driven therapy will be a challenge in the future, phase III studies are ongoing and neo-adjuvant therapy with selpercatinib is being studied.

SUMMARY

The development of selective RET-inhibitors has expanded the therapeutic arsenal to control tumor growth in progressive MTC, with fewer adverse effects than multikinase inhibitors. Future studies should confirm their effectiveness, study neo-adjuvant strategies, and tackle resistance to these inhibitors, ultimately to improve patient outcomes.

Percutaneous thermal ablation of lung metastases from thyroid carcinomas. A retrospective multicenter study of 107 nodules. On behalf of the TUTHYREF network

PURPOSE

To determine efficacy and safety of thermal ablation (TA) for the local treatment of lung metastases of thyroid cancer.

METHODS

We retrospectively studied 47 patients from 10 centers treated by TA (radiofrequency, microwaves, and cryoablation) over 10 years. The endpoints were overall survival (OS), local efficacy, complications (CTCAE classification), and factors associated with survival. OS curves after first TA were built using the Kaplan-Meier method and compared with the log-rank test.

RESULTS

A total of 107 lung metastases during 75 sessions were treated by radiofrequency (n = 56), microwaves (n = 9), and cryoablation (n = 10). Median follow-up time after TA was 5.2 years (0.2-13.3). OS was 93% at 2 years (95% confidence interval (CI): 86-94) and 79% at 3 years (95% CI: 66-91). On univariate and multivariate analysis with a Cox model, histology was the only significant factor for OS. OS at 3 years was 94% for follicular, oncocytic, or papillary follicular variant carcinomas, compared to 59% for papillary, medullary, insular or anaplastic carcinomas (P = 0.0001). The local control rate was 98.1% at 1 year and 94.8% at 2, 3, 4, and 5 years. Morbidity was low with no major complications (grade 4 and 5 CTCAE) and no complications in 29 of 75 sessions (38.7%).

CONCLUSIONS

TA is a useful, safe and effective option for local treatment of lung metastases from thyroid carcinoma. Prolonged OS was obtained, especially for lung metastases from follicular, oncocytic, or papillary follicular variant carcinomas. Achieving disease control with TA delays the need for systemic treatment.

Pulmonary metastasectomy for thyroid cancer as salvage therapy for radioactive iodine-refractory metastases

OBJECTIVES

Distant metastasis arising from thyroid cancer is rare but has been associated with significantly reduced long-term survival, especially when refractory to radioactive iodine ablation. We provide one of the largest studies worldwide reporting the outcome after salvage pulmonary metastasectomy for this entity, aiming to identify prognostic factors and to analyse surgical indication.

METHODS

We retrospectively analysed the medical records of 43 patients who had undergone pulmonary metastasectomy for radioactive iodine-refractory thyroid cancer from 1985 to 2016.

RESULTS

The median follow-up period was 77 (95% confidence interval 41-113) months. Twenty-three (53%) patients were alive at the time of analysis. The majority of tumours were follicular thyroid cancer by histology, with 23% identified as Hurthle cell subtype. Five- and 10-year disease-specific (DS) survival was 84% and 59%, respectively. Thirty-one (72%) patients underwent R0-resection with a 5- and 10-year DS survival of 100% and 77%, respectively. This was significantly reduced to 62% and 22% (P = 0.013) in case of incomplete resection, respectively. Ten years after R0-metastasectomy, 17 (55%) patients were recurrence-free. Systematic mediastinal lymphadenectomy was performed in 16 (37%) patients and was associated with improved long-term DS survival (10 years 88% vs 46%, P = 0.034). Moreover, a reduction of > 80% in serum thyroglobulin levels post-metastasectomy correlates with better long-term DS survival (10 years 81% vs 36%, P = 0.007).

CONCLUSIONS

Pulmonary metastasectomy is associated with good survival for selected patients with radioactive iodine-refractory metastases of differentiated thyroid cancer, especially if R0-resection can be achieved. Moreover, it is worth considering whether a significant reduction of tumour load, as indicated by thyroglobulin serum levels, seems possible.

Papillary Thyroid Carcinoma (PTC) in Children and Adults: Comparison of Initial Presentation and Long-Term Postoperative Outcome in 4432 Patients Consecutively Treated at the Mayo Clinic During Eight Decades (1936-2015)

BACKGROUND

Contemporary guidelines for managing PTC advise an approach wherein primary tumor and regional metastases (RM) are completely resected at first surgery and radioiodine remnant ablation (RRA) is restricted to high-risk patients, policies our group has long endorsed. To assess our therapeutic efficacy, we studied 190 children and 4242 adults consecutively treated during 1936-2015.

SUBJECTS AND METHODS

Mean follow-up durations for children and adults were 26.9 and 15.2 years, respectively. Bilateral lobar resection was performed in 86% of children and 88% of adults, followed by RRA in 30% of children and 29% of adults; neck nodes were excised in 86% of children and 66% of adults. Tumor recurrence (TR) and cause-specific mortality (CSM) details were taken from a computerized database.

RESULTS

Children, when compared to adults, had larger primary tumors which more often were grossly invasive and incompletely resected. At presentation, children, as compared to adults, had more RM and distant metastases (DM). Thirty-year TR rates were no different in children than adults at any site. Thirty-year CSM rates were lower in children than adults (1.1 vs. 4.9%; p = 0.01). Comparing 1936-1975 (THEN) with 1976-2015 (NOW), 30-year CSM rates were similar in MACIS <6 children (p = 0.67) and adults (p = 0.08). However, MACIS <6 children and adults in 1976-2015 had significantly higher recurrence at local and regional, but not at distant, sites. MACIS 6+ adults, NOW, compared to THEN, had lower 30-year CSM rates (30 vs. 47%; p < 0.001), unassociated with decreased TR at any site.

CONCLUSIONS

Children, despite presenting with more extensive PTC when compared to adults, have postoperative recurrences at similar frequency, typically coexist with DM and die of PTC less often. Since 1976, both children and adults with MACIS <6 PTC have a <1% chance at 30 years of CSM; adults with higher MACIS scores (6 or more) have a 30-year CSM rate of 30%.

Systemic treatment and management approaches for medullary thyroid cancer

Although rare, medullary thyroid cancer (MTC) exemplifies the value that ever-expanding knowledge of molecular pathways and mechanisms brings to managing challenging cancers. Although surgery can be curative for MTC in many patients, a substantial proportion of patients present with locoregional or distant metastatic disease. Once distant disease occurs, treatment options are limited, and conventional cancer treatments such as cytotoxic chemotherapy are of minimal benefit. Biomarkers such as calcitonin and carcinoembryonic antigen are important correlates of disease burden as well as predictors of disease progress, including recurrence and survival. MTC is either sporadic (∼75%) or inherited (∼25%) as an autosomal dominant disease. Regardless, germline and somatic mutations, particularly in the rearranged during transfection (RET) proto-oncogene, are key factors in the neoplastic process. Gain-of-function RET mutations result in overactive proteins that lead to abnormal activation of downstream signal transduction pathways, resulting in ligand-independent growth and resistance to apoptotic stimuli. Specific RET mutation variants have been found to correlate with phenotype and natural history of MTC with some defects portending a more aggressive clinical course. Greater understanding of the consequence of the aberrant signaling pathway has fostered the development of targeted therapies. Two small-molecule tyrosine kinase inhibitors, vandetanib and cabozantinib, are currently available as approved agents for the treatment of advanced or progressive MTC and provide significant increases in progression-free survival. Since there have been no head-to-head comparisons, clinicians often select between these agents on the basis of familiarity, patient characteristics, comorbidities, and toxicity profile.

The impact of complete surgical resection of spinal metastases on the survival of patients with thyroid cancer

Spinal metastases (SMs) from thyroid cancers significantly reduce the quality of life by causing pain and neurological deficits and increase mortality. Complete surgical resection of isolated thyroid SMs is a promising treatment option; however, the postoperative outcome is unknown. This study aimed to compare the postoperative courses of patients undergoing complete resection of thyroid SMs with those of patients undergoing incomplete resection, with a minimum 4‐year follow‐up. We performed a retrospective analysis of 32 patients who underwent tumor excision surgery for thyroid SMs at our medical center during a 28‐year period. Twenty patients underwent complete excision, and 12 underwent incomplete excision. Survival was defined as the time from the first spinal surgery to death or last follow‐up. Kaplan–Meier analysis with the long‐rank test was used to compare the overall survival rates between the groups. For all patients, the overall 5‐ and 10‐year survival rates were 71% and 31%, respectively. The median overall survival time was 6.4 years. The patients undergoing complete excision survived longer than those undergoing incomplete excision (5‐year survival: 84% vs. 50%; 10‐year survival: 52% vs. 8%; P < 0.01). Only one patient undergoing complete excision experienced local tumor recurrence in the operated spine, whereas all long‐term survivors (>18 months after surgery) in the incomplete excision group experienced local tumor recurrence and a consequent deterioration in performance status. Complete surgical resection of thyroid SMs, if achievable, has the potential not only to maintain performance status, but also to prolong survival.

Medical management of metastatic medullary thyroid cancer

Medullary thyroid cancer (MTC) is an aggressive form of thyroid cancer that occurs in both heritable and sporadic forms. Discovery that mutations in the rearranged during transfection (RET) proto-oncogene predispose to familial cases of this disease has allowed for presymptomatic identification of gene carriers and prophylactic surgery to improve the prognosis of these patients. A significant number of patients with the sporadic type of MTC and even those with familial disease still present with lymph node or distant metastases, making surgical cure difficult. Over the past several decades, many different types of therapy for metastatic disease have been attempted with limited success. Improved understanding of the molecular defects and pathways involved in both familial and sporadic MTC has resulted in new hope for these patients with the development of drugs targeting the specific alterations responsible. This new era of targeted therapy with kinase inhibitors represents a significant step forward from previous trials of chemotherapy, radiotherapy, and hormone therapy. Although much progress has been made, additional agents and strategies are needed to achieve durable, long-term responses in patients with metastatic MTC. This article reviews the history and results of medical management for metastatic MTC from the early 1970s up until the present day.

Optimal timing of pulmonary metastasectomy--is a delayed operation beneficial or counterproductive?

INTRODUCTION

Pulmonary metastasectomy represents an established approach in the treatment of lung metastases related to several solid malignant tumors, promising the chance of long term survival. Regarding the proper timing of metastasectomy both operation promptly after diagnosis and delayed operation after an interval of 3 months are common practice.

MATERIALS AND METHODS

A systematic Medline search addressing the optimal timing of metastasectomy was performed. Since the search query "timing of metastasectomy" yields only a limited number of articles, the Medline search was expanded to include the main arguments for prompt metastasectomy ("metastases of metastasis", "growth rate of pulmonary metastases") and for delayed metastasectomy.

RESULTS

Based on the data available to date, there is no necessity to expedite the timing of the operation. On the other hand, there is no evidence that a delayed operation, for example after re-staging following an interval of 3 months, provides a benefit.

CONCLUSION

Therefore the timing of metastasectomy should only depend on the patient's requirements, such as general state of health and oncologic considerations, such as promising multimodal therapy concepts, extrathoracal tumor manifestations or oncologic type of the primary tumor. A delayed operation seems justified if the indication for resection is questionable due to a high risk of early multilocal recurrence.

Standard and emerging therapies for metastatic differentiated thyroid cancer

Differentiated thyroid cancer accounts for >90% of cases of thyroid cancer, with most patients having an excellent prognosis. Distant metastases occur in 10%-15% of patients, decreasing the overall 10-year survival rate in this group to 40%. Radioactive iodine has been the mainstay of treatment for distant metastases, with good results when lesions retain the ability to take up iodine. For patients with metastatic disease resistant to radioactive iodine, treatment options are few and survival is poor. Chemotherapy and external beam radiotherapy have been used in these patients, but with disappointing results. In recent years, our understanding of the molecular pathways involved in thyroid cancer has increased and a number of molecular targets have been identified. These targets include the proto-oncogenes BRAF and RET, known to be common mutations in thyroid cancer; vascular endothelial growth factor receptor and platelet-derived growth factor receptor, associated with angiogenesis; and the sodium-iodide symporter, with the aim of restoring its expression and hence radioactive iodine uptake. There are now multiple trials of tyrosine kinase inhibitors, angiogenesis inhibitors, and other novel agents available to patients with metastatic thyroid cancer. This review discusses both traditional and novel treatments for metastatic differentiated thyroid cancer with a particular focus on emerging treatments for patients with radioactive iodine-refractory disease.