Stimulated Raman Scattering Microscopy Reveals Aberrant Triglyceride Accumulation in Lymphatic Metastasis of Papillary Thyroid Carcinoma.

Lipid metabolic alterations are known to play a crucial role in cancer metastasis. As a key hub in lipid metabolism, intracellular neutral lipid accumulation in lipid droplets (LDs) has become a signature of aggressive human cancers. Nevertheless, it remains unclear whether lipid accumulation displays distinctive features in metastatic lesions compared to the primary ones. Here, we integrated multicolor stimulated Raman scattering (SRS) imaging with confocal Raman spectroscopy on the same platform to quantitatively analyze the amount and composition of LDs in intact human thyroid tissues in situ without any processing or labeling. Inspiringly, we found aberrant accumulation of triglycerides (TGs) in lymphatic metastases but not in normal thyroid, primary papillary thyroid carcinoma (PTC), or normal lymph node. In addition, the unsaturation degree of unsaturated TGs was significantly higher in the lymphatic metastases from patients diagnosed with late-stage (T3/T4) PTC compared to those of patients diagnosed with early-stage (T1/T2) PTC. Furthermore, both public sequencing data analysis and our RNA-seq transcriptomic experiment showed significantly higher expression of alcohol dehydrogenase-1B (ADH1B), which is critical to lipid uptake and transport, in lymphatic metastases relative to the primary ones. In summary, these findings unravel the lipid accumulation as a novel marker and therapeutic target for PTC lymphatic metastasis that has a poor response to the regular radioactive iodine therapy.

Dihydrotanshinone I exhibits antitumor effects via ß-catenin downregulation in papillary thyroid cancer cell lines.

Thyroid cancer is the most common endocrine carcinoma and, among its different subtypes, the papillary subtype (PTC) is the most frequent. Generally, PTCs are well differentiated, but a minor percentage of PTCs are characterized by a worse prognosis and more aggressive behavior. Phytochemicals, naturally found in plant products, represent a heterogeneous group of bioactive compounds that can interfere with cell proliferation and the regulation of the cell cycle, taking part in multiple signaling pathways that are often disrupted in tumor initiation, proliferation, and progression. In this work, we focused on 15,16-dihydrotanshinone I (DHT), a tanshinone isolated from Salvia miltiorrhiza Bunge (Danshen). We first evaluated DHT biological effect on PTC cells regarding cell viability, colony formation ability, and migration capacity. All of these parameters were downregulated by DHT treatment. We then investigated gene expression changes after DHT treatment by performing RNA-seq. The analysis revealed that DHT significantly reduced the Wnt signaling pathway, which plays a role in various diseases, including cancer. Finally, we demonstrate that DHT treatment decreases protein levels of ß-catenin, a final effector of canonical Wnt signaling pathway. Overall, our data suggest a possible use of this nutraceutical as an adjuvant in the treatment of aggressive papillary thyroid carcinoma.

Clinical responses to vemurafenib in postoperative recurrence of papillary thyroid carcinoma with esophageal fistula: A case report.

BACKGROUND: While papillary thyroid carcinoma (PTC) generally exhibits a favorable prognosis post-surgery, the poorly differentiated subtype presents elevated rates of postoperative recurrence. Certain aggressive cases demonstrate invasive behavior, compromising adjacent structures and leading to a poor prognosis. This study delineates a unique case of postoperative PTC recurrence, complicated by esophageal fistula, that showed favorable outcomes following brief Vemurafenib treatment. PATIENT DESCRIPTION: A 64-year-old female patient underwent surgical resection for PTC, subsequently experiencing rapid tumor recurrence and development of an esophageal fistula. DIAGNOSIS: The patient was confirmed to have locally advanced PTC through intraoperative cytopathology. The cancer recurred postoperatively, culminating in the formation of an esophageal fistula. METHODS: The patient was administered Vemurafenib at a dosage of 960 mg twice daily following tumor recurrence. RESULTS: A 12-month regimen of targeted Vemurafenib therapy led to a substantial reduction in tumor size. Concurrently, the esophageal fistula underwent complete healing, facilitating successful removal of the gastrostomy tube. The tumor response was classified as stable disease. CONCLUSION SUBSECTIONS: Vemurafenib demonstrates potential as a targeted therapeutic strategy for recurrent PTC harboring the BRAFV600E mutation. This approach may effectively mitigate tumor dimensions and the associated risk of esophageal and tracheal fistulas.

Case Report: Papillary thyroid carcinoma in Goltz-Gorlin syndrome.

Goltz-Gorlin syndrome (GGS), also known as focal dermal hypoplasia, is a rare X-linked disorder caused by pathogenic variants in the PORCN gene and characterized by several abnormalities, including skin and limb defects, papillomas in multiple organs, ocular malformations, and mild facial dysmorphism. To date, only approximately 300 cases have been described in the literature. A 16-year-old female patient, born with multiple congenital dysmorphisms consistent with GGS and confirmed by genetic exam, was referred to our outpatient clinic for the workup of a thyroid nodule. A thyroid ultrasound showed a bilateral nodular disease with a 17-mm large hypoechoic nodule in the right lobe. Cytological exam of fine needle aspiration biopsy was suspicious for malignancy. Thus, she underwent total thyroidectomy plus lymphadenectomy of the right central compartment. A histological exam disclosed a papillary thyroid carcinoma (PTC) with lymph node micrometastases. Radioiodine (131-Iodine) therapy was performed. At 3- and 6-month follow-up, the patient did not present either ultrasound or laboratory PTC recurrence. To our knowledge, we report the first case of PTC in a patient with GGS. Since thyroid cancer is rare among children and adolescents, we hypothesize that the PORCN pathogenic variant could be responsible for tumor susceptibility. We also provide an overview of the clinical findings on GGS patients already reported and discuss the possible pathogenetic mechanism that may underlie this rare condition, including the role of PORCN in tumor susceptibility.

Clinicopathologic Analysis of Micropapillary Urothelial Carcinoma of the Upper Urinary Tract: Implications for HER2-Targeted Therapy.

Introduction/Background To determine the clinical significance of micropapillary urothelial carcinoma (MPUC) of the upper urinary tract (UTUC) and a potential therapeutic strategy. Patients and Methods A retrospective cohort study was conducted to examine the incidence of micropapillary UTUC from 2010 to 2018 and its clinicopathological characteristics. Clinical outcomes and cancer-specific survival (CSS) were compared between MPUC and conventional UTUC matched by stage within a 6-month variation of receiving surgery. Results A total of 24 MPUC cases were identified out of 901 cases (2.7%) of urothelial carcinoma (UC) of the renal pelvis and ureter. MPUC was significantly smaller (<3 cm) and associated with nodal metastasis compared with conventional UTUC (P = .017 & 0.021, respectively); however, no significant difference was observed for lymphovascular invasion, distant metastasis, or CSS (P > 0.50, respectively) compared with match controls. Six MPUC patients (25%) developed metastasis to the liver, lymph nodes, and lung during follow-up. Patients with HER2-positive MPUC (3 of 4) had a significantly higher risk of metastasis compared with HER2-negative MPUC (3 of 20; P = 0.035). Conclusions MPUC is an aggressive variant of UTUC and usually presents as a small locally advanced disease. HER2 immunohistochemistry may identify the subset of patients with micropapillary UTUC that are candidates for targeted therapy.

Papillary thyroid cancer organoids harboring BRAFV600E mutation reveal potentially beneficial effects of BRAF inhibitor-based combination therapies.

BACKGROUNDS: Papillary thyroid cancer (PTC), which is often driven by acquired somatic mutations in BRAF genes, is the most common pathologic type of thyroid cancer. PTC has an excellent prognosis after treatment with conventional therapies such as surgical resection, thyroid hormone therapy and adjuvant radioactive iodine therapy. Unfortunately, about 20% of patients develop regional recurrence or distant metastasis, making targeted therapeutics an important treatment option. Current in vitro PTC models are limited in representing the cellular and mutational characteristics of parental tumors. A clinically relevant tool that predicts the efficacy of therapy for individuals is urgently needed. METHODS: Surgically removed PTC tissue samples were dissociated, plated into Matrigel, and cultured to generate organoids. PTC organoids were subsequently subjected to histological analysis, DNA sequencing, and drug sensitivity assays, respectively. RESULTS: We established 9 patient-derived PTC organoid models, 5 of which harbor BRAFV600E mutation. These organoids have been cultured stably for more than 3 months and closely recapitulated the histological architectures as well as mutational landscapes of the respective primary tumors. Drug sensitivity assays of PTC organoid cultures demonstrated the intra- and inter-patient specific drug responses. BRAFV600E inhibitors, vemurafenib and dabrafenib monotherapy was mildly effective in treating BRAFV600E-mutant PTC organoids. Nevertheless, BRAF inhibitors in combination with MEK inhibitors, RTK inhibitors, or chemotherapeutic agents demonstrated improved efficacy compared to BRAF inhibition alone. CONCLUSIONS: These data indicate that patient-derived PTC organoids may be a powerful research tool to investigate tumor biology and drug responsiveness, thus being useful to validate or discover targeted drug combinations.

Long-term clinical outcomes and prognostic factors for patients with papillary thyroid carcinoma with other organ invasions after adjuvant radioactive iodine.

PURPOSE: Papillary thyroid carcinoma (PTC) with other organ invasions is directly related to patient prognosis and quality of life; however, studies on the clinical outcomes of adjuvant radioactive iodine (RAI) for PTC with other organ invasions are limited. This study aimed to clarify the clinical outcomes and prognostic factors for patients with PTC with other organ invasions after adjuvant RAI. METHODS: Patients with PTC with other organ invasions without distant metastases who underwent surgery and adjuvant RAI were retrospectively reviewed. We evaluated the initial responses based on the American Thyroid Association guidelines and survival rates. Prognostic factors for locoregional recurrence-free survival (LRRFS) were analyzed. RESULTS: Between January 2005 and December 2019, 102 patients were included in the study. Their median age was 55 years. The median follow-up duration was 92 months (range; 30-231 months). The excellent response rate after RAI was 42%. The 7-year overall survival, LRRFS, and recurrence-free survival rates were 100%, 75%, and 75%, respectively. Metastatic lymph node size, resection margin status, and post-RAI suppressed thyroglobulin level were the independent prognostic factors for LRRFS. CONCLUSION: We demonstrated that 75% of patients with PTC with other organ invasions could achieve long-term survival without recurrence after adjuvant RAI. Future development of effective treatment strategies for large metastatic lymph nodes, gross residual tumors, and high serum thyroglobulin levels is warranted.

Relation between surgical oncologic quality indicators for papillary thyroid cancer.

BACKGROUND: It remains unclear how thyroid surgical oncologic quality indicators (TSOQIs) are related to each other, and how to best interpret and apply these measures within the context of surgical quality assurance. We aimed to examine the relation between 3 TSOQIs: postoperative serum thyroglobulin level, 24-hour radioactive iodine uptake (RAIU) and metastatic lymph node ratio (MLNR). METHODS: We conducted a retrospective review of patients who underwent total thyroidectomy for treatment of papillary thyroid cancer (PTC) performed by a single high-volume thyroid surgeon at a tertiary referral centre between 2012 and 2017. To establish the strength of correlation between pairs of quality indicators and the MACIS (metastasis, age, completeness of resection, invasion and size) prognostic score, we performed tests of normality and used the Spearman correlation coefficient to determine the correlation of nonnormal data containing outliers. RESULTS: A total of 139 patients with PTC were included in the study. Their mean MACIS score was 5.0 (standard deviation 1.5). Fifteen patients had high-risk thyroid cancer (MACIS score > 6.99). A weak correlation was found between serum thyroglobulin level and RAIU (r s = 0.27, p = 0.006) and a moderate correlation was found between serum thyroglobulin level and MLNR (r s = 0.40 p = 0.002). A weak correlation between serum thyroglobulin level and MACIS score was also observed (r s = 0.20, p = 0.05). CONCLUSION: Based on our findings, we propose that the postoperative serum thyroglobulin level represents the quality metric that has the most clinical utility because it is measurable in all patients and also correlates with both RAIU and MLNR. With further research, surgeons seeking to evaluate the oncologic quality of thyroidectomy performed for PTC may consider applying a quality indicator to their future practice.

Analysis of Delayed Surgery and Clinical Outcomes in Intermediate- and High-risk Papillary Thyroid Cancer.

CONTEXT: The optimal timing to performing thyroid surgery following a diagnosis of papillary thyroid cancer (PTC) has yet to be fully defined. OBJECTIVE: We aimed to examine if a delayed surgery may worsen the clinical outcome of PTC patients with intermediate- to high-risk of recurrence. METHODS: All consecutive PTC patients with intermediate- to high-risk of recurrence who underwent total thyroidectomy and radioactive iodine (RAI) ablation at 3 tertiary hospitals in southwest China were retrospectively included. Excellent response at 1-year follow-up after initial therapy was defined as no clinical, imaging, or biochemical evidence of PTC. Association of the timing of surgery and excellent response rates. RESULTS: The study included 871 patients. The median time interval between PTC diagnosis and surgery was 2 months (range, 1-87 months). Patients were divided according to the timing of surgery, < 6 months (group A, 624/871 [71.6%]), ≥ 6 to 11 months (group B, 123/871 [14.1%]), or ≥ 12 months (group C, 124/871 [14.2%]). One year after initial therapy, 64.7%, 71.5%, and 66.1% of patients in groups A, B, and C, respectively, achieved excellent response (P = 0.27). The lack of impact of surgery timing was observed across intermediate- to high-risk classifications and all T stage categories. These findings did not change when we separately analyzed the groups according to RAI dose (intermediate-dose group: ≤ 3.7 GBq [n = 654], and high-activity group: 5.5 GBq [n = 217]) further subdivided according to the timing of surgery. CONCLUSION: Timing of surgery does not seem to affect short-term disease outcomes in intermediate- to high-risk PTC patients. Further research is necessary to assess the impact of delayed surgery on long-term prognosis.

Management dilemma in metastatic papillary thyroid carcinoma.

Papillary thyroid cancer is the most common type of well-differentiated thyroid cancer. It is associated with a survival rate greater than 95% with appropriate treatment, particularly in younger patients. We present the unique case of a 25-year-old male with severe Autistic spectrum disorder (ASD) with a right level V neck mass of several months. Due to his severe ASD, his first assessment was conducted in the hospital foyer, and every subsequent clinical assessment and blood test required a general anaesthetic (GA). He was subsequently diagnosed with T2 N1b M0 (Stage I) papillary thyroid cancer. He required extensive multidisciplinary team (MDT) input to determine the goal for his treatment whilst taking into consideration perioperative care, wound management, compliance with exam and blood tests, radioactive iodine administration and lifelong medication requirements if total thyroidectomy was considered. Following multiple MDT and family meetings, the decision was made to proceed with right hemi-thyroidectomy, right level I-V and central neck dissection. He required one-week stay in the intensive care unit under sedation post-operatively, and was discharged from hospital a further six days later with no complications. He is currently being followed-up every six months which presents its own challenges. This case highlights the extraordinary challenges and considerations that need to be made when dealing with surgical pathology in a patient with severe intellectual disability, even in the setting of a relatively common surgical pathology.

Reactive arthritis following treatment with intravesical Bacillus Calmette-Guerin for papillary carcinoma of bladder.

A man in his 60s developed reactive arthritis following treatment with intravesical Bacillus Calmette-Guerin (iBCG) for papillary carcinoma of bladder. Evaluation revealed leucocytosis and raised inflammatory markers. HLA B27 was positive. Based on the temporal relationship, it was attributed to BCG-related reactive arthritis. iBCG was stopped. Treatment with non-steroidal anti-inflammatory drugs (NSAIDS) and glucocorticoids were ineffective. Prolonged course of disease-modifying antirheumatic drugs (DMARDS) was required which aided in alleviation of symptoms and sustained remission. Intravesical BCG therapy is a treatment for bladder cancer. It is rarely associated with reactive arthritis, which responds to discontinuation of iBCG and treatment with NSAIDS and/or short-term glucocorticoids. iBCG-related reactive arthritis commonly has an acute/subacute course. Chronic arthritis as observed in our case requiring prolonged treatment with DMARDS is rare.

Fumarate inhibits PTEN to promote tumorigenesis and therapeutic resistance of type2 papillary renal cell carcinoma.

Fumarate is an oncometabolite. However, the mechanism underlying fumarate-exerted tumorigenesis remains unclear. Here, utilizing human type2 papillary renal cell carcinoma (PRCC2) as a model, we show that fumarate accumulates in cells deficient in fumarate hydratase (FH) and inhibits PTEN to activate PI3K/AKT signaling. Mechanistically, fumarate directly reacts with PTEN at cysteine 211 (C211) to form S-(2-succino)-cysteine. Succinated C211 occludes tethering of PTEN with the cellular membrane, thereby diminishing its inhibitory effect on the PI3K/AKT pathway. Functionally, re-expressing wild-type FH or PTEN C211S phenocopies an AKT inhibitor in suppressing tumor growth and sensitizing PRCC2 to sunitinib. Analysis of clinical specimens indicates that PTEN C211 succination levels are positively correlated with AKT activation in PRCC2. Collectively, these findings elucidate a non-metabolic, oncogenic role of fumarate in PRCC2 via direct post-translational modification of PTEN and further reveal potential stratification strategies for patients with FH loss by combinatorial AKTi and sunitinib therapy.

First American Cancer Patient to Receive Dicycloplatin (DCP) Chemotherapy Achieves Remission After Seven Weeks of DCP Capsules - A Case Report.

BACKGROUND: The majority of bladder cancer patients experience recurrence. Cisplatin is the standard chemotherapy for muscle-invasive bladder cancer though adverse effects are often severe. CASE REPORT: Intravenous (IV) dicycloplatin (DCP) sustained remission in an American bladder cancer patient for five years. A recurrent mass was observed in July 2021. The patient received DCP capsules for seven weeks with no significant side-effects. Complete blood count with differential and a basic metabolic panel showed no adverse effects of DCP capsules on the bone marrow, liver or renal parameters. Cystoscopy after oral DCP found no evident bladder tumors; cytology was negative for high-grade urothelial carcinoma. CONCLUSION: In this patient, DCP-capsules appeared to be as effective as DCP-IV for achieving bladder cancer remission. Both forms of DCP chemotherapy are convenient, active against several cancer types, with decreased adverse effects compared to cisplatin. Both have been available for treating cancer patients in China. A USA clinical trial of DCP in bladder and other cancers appears warranted.

Establishment of Patient-derived Preclinical Models for Invasive Papillary Cholangiocarcinoma.

BACKGROUND/AIM: Invasive papillary cholangio-carcinoma (IPC) is a minor subtype of extrahepatic cholangiocarcinoma. However, its etiology and characteristics remain unknown because of the unavailability of in vitro and in vivo models. We aimed to establish a novel preclinical model for translational research of IPC. MATERIALS AND METHODS: A patient-derived xenograft (PDX) was engrafted in NOG mice and the cell line National Cancer Center human IPC (NCChIPC) was subsequently established from the PDX tumors. Immunohistochemistry and RNA-sequencing were used to determine the retention of original characteristics of patient tissues. RESULTS: PDX tumors showed successful amplification, and the NCChIPC-derived xenograft largely retained the histopathological features of the original tumor with CK19, MUC1 and MUC5AC expression. Transcriptome analysis showed a high correlation between patient and preclinical models. Additionally, anticancer drugs response was analyzed in the NCChIPC PDX. CONCLUSION: These novel preclinical models here will help elucidate IPC etiology and facilitate translational research.

Literature review and case report of bilateral intracystic papillary carcinoma associated with an invasive ductal carcinoma in a male breast.

Intracystic papillary carcinoma (IPC) is a rare tumor with good prognosis that occurs in only 5% to 7.5% of male breast cancer. We report a case of a 46-year-old man who presented a brown nipple discharge a few months ago. He had a bilateral IPC and an invasive ductal carcinoma on the right breast. A double mastectomy was then performed with a bilateral sentinel lymph node biopsy, and he received chemotherapy, radiotherapy, and hormonotherapy. Two years after the diagnosis, the patient recovered and was free of recurrence. Considering the scarcity of this tumor type, we conducted a systematic literature review on the PubMed of all the cases of IPC in men. The clinical presentation, imaging, and treatment of the 43 case reports from the 41 articles selected were described. Furthermore, no clear guidelines for IPC management are available. Conservative surgery should also be preferred, and a sentinel lymph node biopsy should be performed systematically. Moreover, radiotherapy should be proposed in the case of conservative surgery, and hormone therapy could be proposed in the case of invasive IPC or IPC associated with a ductal carcinoma in situ.

The magnitude of increased Levothyroxine dose during pregnancy in patients on thyroid-stimulating hormone (TSH) suppression treatment after total thyroidectomy for papillary carcinoma.

The dose of L-T4 replacement for hypothyroidism often needs to be increased after pregnancy. In our institution, patients are instructed to double the dose 2 days a week after pregnancy. However, there is scarce evidence supporting the need for a dose increase after pregnancy in patients with preconception thyroid-stimulating hormone (TSH) suppression (TSH <0.3 µIU/mL). This study aimed to determine the need for a dose increase in L-T4 among women with a TSH-suppressive dose of L-T4 before pregnancy. In this retrospective observational study, between January 2008 and December 2018, we analyzed 166 pregnancies in 134 patients on TSH suppression treatment after total thyroidectomy for papillary carcinoma. Thyroid function tests were performed before and in the first trimester of pregnancy. The dose was adjusted and maintained during the first trimester of pregnancy in 76 pregnancies (group A) and 90 pregnancies (group B), respectively. The median serum TSH level was significantly lower in group A than that in group B (0.014 µIU/mL (IQR, 0.005-0.071) vs. 0.155 µIU/mL (IQR, 0.021-0.657), p < 0.001). TSH suppression could not be maintained after pregnancy in 15.8% and 38.9% of the pregnancies in groups A and B, respectively. Increasing the post-pregnancy dose by an average of 27.4% resulted in maintenance of TSH suppression after pregnancy in 84.2% of pregnancies. In conclusion, this study suggests that increasing the L-T4 dose after pregnancy may be appropriate in postoperative thyroid cancer patients whose serum TSH levels should be suppressed.

A rare case of ciliated muconodular papillary tumor accompanied with adenocarcinoma in situ.

BACKGROUND: Ciliated muconodular papillary tumor (CMPT) is an incredibly rare pulmonary tumor. Currently, little is known about CMPT, and it has not yet been classified by the World Health Organization. The clinical manifestation of CMPT is nonspecific and the diagnosis is only based on pathology. CMPT has been documented in limited reports as a benign tumor, thus the treatment is typically with surgical excision if a solid tumor is identifiable. The prognosis of CMPT is very positive, as no recurrence has been reported in the limited literature available. However, CMPT accompanied with adenocarcinoma in situ has not been reported previously in the literature. CASE PRESENTATION: In this report, we presented a case of a 53-year-old male smoker with CMPT associated with adenocarcinoma in situ. This diagnosis was confirmed by pathological examination, including immunohistostaining. No solid resectable lesion was identified on CT scan; therefore, no surgery was performed. The patient's adenocarcinoma in situ was disseminated in both lungs, thus chemotherapeutic treatment with cisplatin and pemetrexed was given. The patient will be continually followed up closely on a wait-and-watch basis. CONCLUSIONS: In summary, our report reveals a unique case of CMPT in conjunction with adenocarcinoma in situ, potentially revealing an association between CMPT and malignancy which has not been previously reported. More similar case studies will be beneficial to determine the authentic relationship between CMPT and adenocarcinoma in situ.

Checkpoint inhibitors in metastatic papillary renal cell carcinoma.

Papillary Renal Cell Carcinoma (pRCC) is the most common non-clear cell RCC (nccRCC) and a distinct entity, although heterogenous, associated with poor outcomes. The treatment landscape of metastatic pRCC (mpRCC) relied so far on targeted therapies, mimicking previous developments in metastatic clear-cell renal cell carcinoma. However, antiangiogenics as well as mTOR inhibitors retain only limited activity in mpRCC. As development of immune checkpoint inhibitors (ICI) is now underway in patients with mpRCC, we aimed at discussing early activity data and potential for future therapeutic strategies in monotherapy or combination. Expression of immune checkpoints such as PD-L1 and infiltrative immune cells in pRCC could provide insights into their potential immunogenicity, although this is currently poorly described. Based on retrospective and prospective data, efficacy of ICI as single agent remains limited. Combinations with tyrosine-kinase inhibitors, notably with anti-MET inhibitors, harbor promising response rates and may enter the standard of care in untreated patients. Collaborative work is needed to refine the molecular and immune landscape of pRCC, and pursue efforts to set up predictive biomarker-driven clinical trials in these rare tumors.

Pembrolizumab monotherapy for the treatment of high-risk non-muscle-invasive bladder cancer unresponsive to BCG (KEYNOTE-057): an open-label, single-arm, multicentre, phase 2 study.

BACKGROUND: Standard treatment for high-risk non-muscle-invasive bladder cancer is transurethral resection of bladder tumour followed by intravesical BCG immunotherapy. However, despite high initial responses rates, up to 50% of patients have recurrence or become BCG-unresponsive. PD-1 pathway activation is implicated in BCG resistance. In the KEYNOTE-057 study, we evaluated pembrolizumab, a PD-1 inhibitor, in BCG-unresponsive non-muscle-invasive bladder cancer. METHODS: We did this open-label, single-arm, multicentre, phase 2 study in 54 sites (hospitals and cancer centres) in 14 countries. In cohort A of the trial, adults aged 18 years or older with histologically confirmed BCG-unresponsive carcinoma in situ of the bladder, with or without papillary tumours, with an Eastern Cooperative Oncology Group performance status of 0-2, and who were ineligible for or declined radical cystectomy were enrolled. All enrolled patients were assigned to receive pembrolizumab 200 mg intravenously every 3 weeks for up to 24 months or until centrally confirmed disease persistence, recurrence, or progression; unacceptable toxic effects; or withdrawal of consent. The primary endpoint was clinical complete response rate (absence of high-risk non-muscle-invasive bladder cancer or progressive disease), assessed by cystoscopy and urine cytology approximately 3 months after the first dose of study drug. Patient follow-ups were done every 3 months for the first 2 years and every 6 months thereafter for up to 5 years. Efficacy was assessed in all patients who received at least one dose of the study drug and met BCG-unresponsive criteria. Safety was assessed in all patients who received at least one dose of the study drug. This trial is registered with ClinicalTrials.gov number, NCT02625961, and is ongoing. FINDINGS: Between Dec 9, 2015, and April 1, 2018, we screened 334 patients for inclusion. 186 patients did not meet inclusion criteria, and 47 patients were assigned to cohort B (patients with BCG-unresponsive high grade Ta or any grade T1 papillary disease without carcinoma in situ; results will be reported separately). 101 eligible patients were enrolled and assigned to receive pembrolizumab. All 101 patients received at least one dose of the study drug and were included in the safety analysis. Five patients had disease that did not meet the US Food and Drug Administration definition of BCG-unresponsive non-muscle-invasive bladder cancer and were therefore not included in the efficacy analysis (n=96). Median follow-up was 36·4 months (IQR 32·0-40·7). 39 (41%; 95% CI 30·7-51·1) of 96 patients with BCG-unresponsive carcinoma in situ of the bladder with or without papillary tumours had a complete response at 3 months. Grade 3 or 4 treatment-related adverse events occurred in 13 (13%) patients; the most common were arthralgia (in two [2%] patients) and hyponatraemia (in three [3%] patients). Serious treatment-related adverse events occurred in eight (8%) patients. There were no deaths that were considered treatment related. INTERPRETATION: Pembrolizumab monotherapy was tolerable and showed promising antitumour activity in patients with BCG-unresponsive non-muscle-invasive bladder cancer who declined or were ineligible for radical cystectomy and should be considered a a clinically active non-surgical treatment option in this difficult-to-treat population. FUNDING: Merck Sharp & Dohme.

MANAGEMENT OF ENDOCRINE DISEASE: Papillary thyroid microcarcinoma: toward an active surveillance strategy.

In the last decades, the incidence of thyroid cancer (TC) has more than doubled, but the disease-specific mortality rate was stable. To date, 30-40% of all TC is represented by papillary microcarcinomas (mPTC), an indolent tumor, that probably remained undiagnosed before routine ultrasound use. In 1993, Miyauchi was the first who hypothesized a conservative approach for low-risk mPTC and introduced the concept of active surveillance (AS) in its clinical management. The progression rate of mPTC during AS was low and delaying surgery did not impact the efficacy of treatment or outcome. Since then, several authors from all over the world have reported their experience of AS in mPTCs. As suggested by current guidelines, AS can be considered as an alternative to immediate surgery to avoid overtreatment in low-risk mPTC and may be the strategy to avoid complications from unnecessary surgery. In the last years, AS inclusion criteria have been extended to both bigger tumors and to younger/healthier patients. The adoption of AS should take into consideration not only tumor characteristics but also patient psychological profiles and medical team expertise. Its safety and efficacy have been demonstrated in long-term outcome studies and in other types of tumors; however, skepticism in patients, families and physicians should be overcome by strong recommendations coming from scientific guidelines. This review analyses the several and different experiences of AS and the potential obstacles in implementing it as a routine approach in mPTC patients.