Previous External Beam Radiation Treatment Exposure Does Not Confer Worse Outcome for Patients with Differentiated Thyroid Cancer

A prediction model based on random survival forest analysis of the overall survival of elderly female papillary thyroid carcinoma patients: a SEER-based study

OBJECTIVE

Papillary thyroid carcinoma (PTC) is a common malignancy whose incidence is three times greater in females than in males. The prognosis of ageing patients is poor. This research was designed to construct models to predict the overall survival of elderly female patients with PTC.

METHODS

We developed prediction models based on the random survival forest (RSF) algorithm and traditional Cox regression. The data of 4539 patients were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Twelve variables were analysed to establish the models. The C-index and the Brier score were selected to evaluate the discriminatory ability of the models. Time-dependent receiver operating characteristic (ROC) curves were also drawn to evaluate the accuracy of the models. The clinical benefits of the two models were compared on the basis of the DCA curve. In addition, the Shapley Additive Explanations (SHAP) plot was used to visualize the contribution of the variables in the RSF model.

RESULTS

The C-index of the RSF model was 0.811, which was greater than that of the Cox model (0.781). According to the Brier score and the area under the ROC curve (AUC), the RSF model performed better than the Cox model. On the basis of the DCA curve, the RSF model demonstrated fair clinical benefit. The SHAP plot showed that age was the most important variable contributing to the outcome of PTC in elderly female patients.

CONCLUSIONS

The RSF model we developed performed better than the Cox model and might be valuable for clinical practice.

Treating secondary malignant neoplasms: A burden of childhood cancer survivors

Each year approximately 35,000 children and adolescents are diagnosed with cancer in Europe. Five-year survival rates have improved and now reach 80% in most European countries, thanks to a combination of chemotherapy, radiotherapy, and surgery. To date, there are more than 44,000 Italians still living several years after being diagnosed with cancer in developmental age. The risk of premature morbidity and mortality for cancer survivors is well known and documented. Approximately 60% of survivors of cancer in childhood and adolescence have at least one chronic health condition in later life, and more than one in four develop severe or life-threatening disorders. Among the various long-term iatrogenic sequelae of cancer treatments, the most worrisome are second malignant neoplasms. We reported on our mono-institutional experiences of screening and treating secondary breast cancer, secondary thyroid cancer and secondary osteosarcoma. Recommendations on the surveillance needed for cancer survivors because of the risk of late effects of their disease or its treatment suggest that discussing the potential problems early on can be crucial to a patient's future health. These considerations and our consolidated experience strengthen our conviction that survivors of cancer in childhood and adolescence who develop second malignant neoplasms should be treated at highly-specialized centers. Multidisciplinary care requires close communications and high levels of up-to-date professional expertise. This challenging area of health care is also changing rapidly because cancer survivorship is a work in progress, but we cannot wait for definitive conclusions on many aspects because this will take decades, especially for pediatric patients.

Thyroid cancer in children: A multicenter international study highlighting clinical features and surgical outcomes of primary and secondary tumors

BACKGROUND

Thyroid gland malignancies are rare in pediatric patients (0.7% of tumors); only 1.8% are observed in patients aged <20 years, with a higher prevalence recorded in women and adolescents. Risk factors include genetic syndromes, MEN disorders, autoimmune diseases, and exposure to ionizing radiation. Radiotherapy is also associated with an increased risk of secondary thyroid cancer. This study describes the clinical features and surgical outcomes of primary and secondary thyroid tumors in pediatric patients.

METHODS

Institutional data were collected from eight international surgical oncology centers for pediatric patients with thyroid cancer between 2000 and 2020. Statistical analyses were performed using the GraphPad Prism software.

RESULTS

Among 255 total cases of thyroid cancer, only 13 (5.1%) were secondary tumors. Primary thyroid malignancies were more likely to be multifocal in origin (odds ratio [OR] 1.993, 95% confidence interval [CI].7466-5.132, p = 0.2323), have bilateral glandular location (OR 2.847, 95% CI.6835-12.68, p = 0.2648), and be metastatic at first diagnosis (OR 1.259, 95% CI.3267-5.696, p > 0.999). Secondary tumors showed a higher incidence of disease relapse (OR 1.556, 95% CI.4579-5.57, p = 0.4525) and surgical complications (OR 2.042, 95% CI 0.7917-5.221, p = 0.1614), including hypoparathyroidism and recurrent laryngeal nerve injury. The overall survival (OS) was 99% at 1 year and 97% after 10 years. No EFS differences were evident between the primary and secondary tumors (chi-square 0.7307, p = 0.39026).

CONCLUSIONS

This multicenter study demonstrated excellent survival in pediatric thyroid malignancies. Secondary tumors exhibited greater disease relapse (15.8 vs. 10.5%) and a higher incidence of surgical complications (36.8 vs. 22.2%).

Advancements in the treatment of differentiated thyroid cancer

Derived from follicular epithelial cells, differentiated thyroid cancer (DTC) accounts for the majority of thyroid malignancies. The threefold increase in DTC incidence over the last three decades has been largely attributed to advancements in detection of papillary thyroid microcarcinomas. Efforts to address the issue of overtreatment have notably included the reclassification of encapsulated follicular variant papillary thyroid cancers (EFVPTC) to non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). In the last 5 years, the overall management approach for this relatively indolent cancer has become less aggressive. Although surgery and radioiodine ablation remain the mainstay of DTC therapy, the role of active surveillance is being explored. Furthermore, the most recent American Thyroid Association (ATA) guidelines offer flexibility between lobectomy and total thyroidectomy for thyroid nodules between 1 cm and 4 cm in the absence of extrathyroidal extension or nodal disease. As our understanding of the natural history and molecular underpinnings of DTC evolves, so might our approach to managing low-risk patients, obviating the need for invasive intervention. Simultaneously, advances in interventional and systemic therapies have greatly expanded treatment options for high-risk surgical candidates and patients with widespread disease, and continue to be areas of active investigation. Continued research efforts are essential to improve our ability to offer effective individualized therapy to patients at all disease stages and to reduce the incidence of recurrent and progressive disease.

Radiation-induced papillary thyroid cancer: is it a distinct clinical entity?

PURPOSE OF REVIEW

To present the current status of knowledge regarding radiation-induced papillary thyroid cancer (RIPTC), defining its epidemiologic, pathologic, and clinical characteristics, with ensuing possible therapeutic and prognostic consequences.

RECENT FINDINGS

Cumulative evidence shows that RIPTC resembles sporadic papillary thyroid cancer (PTC) of comparable age, both in terms of clinical-pathological features and prognosis. Therefore, more aggressive treatment does not seem to be required when managing RIPTC as its prognosis is comparable to that of never-irradiated patients.

SUMMARY

Radiation exposure in childhood is a well-documented risk factor for development of PTC. Therefore, increased exposure to medical or environmental radiation may be in part responsible, along with increased screening, of the recent burgeoning incidence of PTC. A specific morphological and molecular portrait of RIPTC is unlikely to exist. The more aggressive histologic and clinical features initially reported in radiation-induced cases are consistent with the expectations in nonradiation-related PTC of a comparable age. Aggressive histology, nodal, and distant metastases correlate with early age at onset rather than with radiation exposure. Although relapses are frequent in children, long-term cancer-specific mortality is approximately 1%, lower than that observed for adults and comparable between irradiated and nonirradiated cohorts. RIPTC does not require more aggressive surgery or more adjuvant treatments, as prognosis is as good as that of sporadic PTC when matched for stage and treatment received.