Multiple Metastases Research Articles

Abstract C004: Glucocorticoids establish a metastatic-promoting tumor microenvironment in a PDAC mouse model

Abstract Disseminated cancer cells (DCCs) arriving to a new organ may either proliferate and form metastasis, get eliminated by immune cells, or enter a quiescent stage. The factors that determine the DCCs’ fate, including getting quiescent DCCs to re-initiate proliferation and successfully evade the immune system, remain poorly understood, in part due to the lack of robust mouse models. We established a pancreatic ductal adenocarcinoma (PDAC) mouse model of dormant DCCs in the liver. An “immunization protocol” was used to mimic PDAC resection in patients: KPC1199 PDAC cells were injected to establish primary tumors and allow an adaptive immune response to develop against the cancer cells; the tumors were surgically resected; and new KPC1199 cells were intrasplenically injected to establish experimental liver metastases. The overwhelming majority of the KPC1199 cells were eliminated. No metastases spontaneously formed during 20 months of observation, but about 3-8 sporadic, single DCCs were found per liver cross section, and 94% of these DCCs were negative for proliferation markers. Although the model is based on entraining an adaptive immune response, T cell depletion resulted in only 25-30% of mice developing just 1-3 metastases each. This suggests that T cell depletion results in metastasis from the small percentage of DCCs that were proliferating. The DCC-hosting mice therefore represents of model to identify factors that can trigger further DCC proliferation and metastatic recurrence. Patients with PDAC often experience significant stress, leading to excess of endogenous glucocorticoids (GCs). Additionally, synthetic GCs are used during e.g., chemotherapy to manage side effects. To mimic elevated GC levels in patients, we treated DCC-hosting mice with synthetic GCs resulting in an increased percentage of proliferating DCCs (increasing from <6% of the examined cells in control mice to about 36%). Yet, no metastases formed. GC treatment also decreased T cell and increased neutrophil liver infiltration. Neutrophils can form protease-containing neutrophil extracellular traps (NETs), which we previously showed trigger DCC proliferation by proteolytic remodeling of the extracellular matrix protein laminin. We found that neutrophils from GC-treated mice spontaneously formed more NETs, and additionally, NET-generated laminin remodeling was observed in the liver metastasis. Together, the data suggest, that GC treatment drive quiescent DCCs to proliferate via neutrophils but alone this is insufficient to cause metastases. Consistent with this interpretation, T cell depletion combined with GC treatment resulted in multiple metastases in all mice examined. Of note, deleting the GC receptor in the DCCs did not reduce metastases, supporting that GCs act on the host and not the cancer cells. In conclusion, our data suggest that for quiescent DCCs to form metastases, they need signals that trigger proliferation and simultaneously, they must overcome immune surveillance. Elevated GC levels or GC treatment in immune suppressed individuals represents such a scenario. Citation Format: Xiao Han, Xueyan He, Yuan Gao, Sicheng Pan, Mikala Egeblad. Glucocorticoids establish a metastatic-promoting tumor microenvironment in a PDAC mouse model [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C004.

CHALLENGES IN BRAIN METASTASES DIAGNOSIS AND TREATMENT

Although brain metastases are the most frequent type of intracranial tumors, their diagnosis and treatment is still challenging. They have poor prognosis and life expectancy is short, as brain metastases appear in advanced stage cancers. In U.S., the rate of recently discovered cancer that will evolve with brain metastases is considered to be 6-14%. Left untreated, brain metastases become lethal in less than 2 months. The most common primary cancers that develop brain metastases are lung, breast, melanoma and colorectal. In our department, approximately 60 patients with brain tumors were diagnosed after surgery with brain metastases in the last 10 years. The most common cancer to metastasize by far was lung cancer, with a mean age at diagnosis 60 years old, affecting mostly smoking men. The majority of patients presented with multiple metastases, unaware of the primary disease and without conducting any oncological treatment prior to admission in our departement. We observed that COVID-19 pandemic period highly affected patients with cancer. The number of patients with brain metastases operated on in our department has drastically decreased in that period. There were a lot of reasons why cancer patients among which being the imposibility to reach emergency rooms without having COVID-19 symptoms and difficulty of reaching radiology centers for early imaging. Most of the patients presented in the Emergency Department with multiple brain metastases, comatose or with focal neurological deficits installed long before presentation, regardless of their primary cancer, thus making neurosurgery an impractical option for most of these cases. Although there have been significant advances in systemic oncological treatment and radiotherapy, surgery remains an essential method of managing brain metastases, even in cases presenting with multiple lesions. Careful patient selection is essential in obtaining the best outcome.

Pituitary carcinoma with multiple metastases: A case report and literature review

Pituitary carcinoma is traditionally defined as a tumor of adenohypophyseal cells that metastasizes systemically or craniospinally. They account for approximately 0-2% of all pituitary tumors. Their diagnosis and treatment is challenging. We report the case of a woman who was initially diagnosed with adenoma and scheduled for surgery. An MRI of the brain three weeks later showed metastatic lesions. The patient died ten days after surgery due to adrenal crisis. The development of pituitary carcinoma is extremely unusual. It could be misdiagnosed with an invasive pituitary adenoma. Until recently, treatment of pituitary carcinoma was mainly palliative and did not appear to increase overall survival.

Case report: A rare case of breast and multiorgan metastases secondary to papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is generally considered a highly indolent endocrine malignancy, often accompanied by cervical lymph node metastasis and rarely involving distant metastases. We present a rare case of a 37-year-old woman with PTC, who exhibited regional lymph node metastasis, right breast metastasis, and probable right psoas major and multiple bone metastases. Initial symptoms included hoarseness, and subsequent examination revealed a secondary malignant tumor in the right breast, originating from the thyroid gland. This case highlights an unusual pattern of multiple systemic metastasis in PTC, particularly the rare occurrence of breast metastasis.

Sialic Acids Blockade-Based Chemo-Immunotherapy Featuring Cancer Cell Chemosensitivity and Antitumor Immune Response Synergies.

Immune checkpoint blockade (ICB) has significantly improved the prognosis of patients with cancer, although the majority of such patients achieve low response rates; consequently, new therapeutic approaches are urgently needed. The upregulation of sialic acid-containing glycans is a common characteristic of cancer-related glycosylation, which drives disease progression and immune escape via numerous pathways. Herein, the development of self-assembled core-shell nanoscale coordination polymer nanoparticles loaded with a sialyltransferase inhibitor, referred to as NCP-STI which effectively stripped diverse sialoglycans from cancer cells, providing an antibody-independent pattern to disrupt the emerging Siglec-sialic acid glyco-immune checkpoint is reported. Furthermore, NCP-STI inhibits sialylation of the concentrated nucleoside transporter 1 (CNT1), promotes the intracellular accumulation of anticancer agent gemcitabine (Gem), and enhances Gem-induced immunogenic cell death (ICD). As a result, the combination of NCP-STI and Gem (NCP-STI/Gem) evokes a robust antitumor immune response and exhibits superior efficacy in restraining the growth of multiple murine tumors and pulmonary metastasis. Collectively, the findings demonstrate a novel form of small molecule-based chemo-immunotherapy approach which features sialic acids blockade that enables cooperative effects of cancer cell chemosensitivity and antitumor immune responses for cancer treatment.

Identification of the First Case of Dedifferentiated Liposarcoma in Amphibians: Insights from Maculopaa medogensis

Dedifferentiated liposarcoma (DDLPS) is a rare and aggressive type of cancer primarily reported in humans, with no documented cases in animals. In this study, we present the first case of DDLPS in a wild amphibian species, Maculopaa medogensis. The tumor was discovered during a routine examination and diagnosed through a combination of advanced diagnostic methods, including micro-CT imaging, gross anatomical inspection, histological analysis, and immunohistochemistry. The tumor exhibited both well-differentiated and dedifferentiated components, characteristic of DDLPS, with evidence of tissue invasion and multiple metastases. Immunohistochemical analysis revealed the strong positive expression of markers such as S100A4, CDK4, MDM2, and CD34, while Leptin expression was negative, further confirming the diagnosis. This is the first reported case of DDLPS in a non-human species, expanding our understanding of cancer in wildlife and underscoring the significance of amphibians as environmental indicators. These findings provide valuable insights for veterinary medicine and wildlife conservation, particularly regarding the role of environmental stressors in cancer development. This study highlights the need for comprehensive diagnostic approaches in wildlife pathology.

Significance of Lateral Pelvic Lymph Node Dissection in Resectable Stage IV Low Rectal Cancer: Experience from a Single Center in Japan.

To investigate the significance of lateral pelvic lymph node dissection (LPLND) in resectable stage IV low rectal cancers, reviewing the treatment outcomes from a single cancer center dedicated to LPLND. Consecutive 56 patients with stage IV low rectal cancers who underwent primary tumor resection (PTR) between 2007 and 2022 were identified. Sixteen patients with non-curative PTR were excluded, and 40 with curative PTR were analyzed. The dominant metastatic organ was the liver in 30 (75.0%) patients, followed by the lung in 9 (22.5%). Seven (17.5%) patients had multiple organ metastasis. Five of 40 patients had cT1bN0 or cT2N0 disease, 8 did not receive LPLND for other reasons, and accordingly, 27 (67.5%) finally received LPLND. A total of 15 patients (37.5% of all 40 cases and 55.5% of 27 LPLND cases) had LPLN metastasis. Six (15.0%) patients had bilateral metastasis, and 6 (15.0%) had LD3 metastasis. Eight (20.0%) patients developed local recurrence (LR), and the 5Y-LR rate was 22.3%. Twelve (30.0%) patients underwent preceding chemotherapy before PTR, 26 (65.0%) received chemotherapy after PTR, and 23 (57.5%) achieved complete resection. Twelve (52.2%) of 23 patients developed distant recurrence after complete resection. 5Y-overall survival for all patients was 42.4%. A high rate of LPLN metastasis implies the significance of management for LPLN metastasis; meanwhile, an unsatisfactory complete resection rate and overall survival implies that LPLN metastasis in this cohort should be dealt with as a systemic disease.

Surgical Treatment and Clinical Evaluation of Calvarial Metastases.

The aim of this study is to explore surgical treatment techniques and clinical attributes associated with calvarial metastases, while providing a comprehensive review of the treatment experiences relevant to this particular type of tumor. This study involves a retrospective analysis of clinical data from 12 patients diagnosed with calvarial metastatic tumors who underwent surgical intervention. Among these patients, 5 had a history of previous malignant tumor resections, while 7 presented with calvarial metastatic tumors as their initial symptom. In all cases, the surgical approach consisted of calvarial tumor resection followed by titanium mesh repair. Following the surgical intervention, all patients underwent a comprehensive course of treatment, encompassing both local radiotherapy and systemic chemotherapy. In 1 instance, a patient presented with multiple tumors located in the central area of the frontal bone and the right temporal bone. The larger tumor situated in the middle of the frontal bone was surgically excised, while the tumor in the right temporal bone was treated using radiotherapy. In 2 cases characterized by multiple metastases within the skull, a comprehensive excision of all tumors was accomplished in a single surgical procedure. In the remaining cases featuring a solitary metastatic growth, the respective tumors were surgically removed. There were 10 instances of dura mater invasion and 3 cases involving the invasion of brain tissue. Pathologic examinations revealed 1 case of metastatic lung adenocarcinoma, 1 case of metastatic paraganglioma, 1 case of metastatic hepatocellular carcinoma, 2 cases of metastatic thyroid carcinoma, and 7 cases of metastatic clear cell renal cell carcinoma. Throughout the follow-up period, spanning from 14 to 90 months, various outcomes were noted. These included three occurrences of in situ recurrence. In addition, 1 patient required 3 distinct surgical interventions, while 2 other patients underwent 2 separate surgical procedures each. Notably, 1 of these cases involved the exposure of the titanium mesh on the scalp, necessitating the removal of the titanium mesh. Regrettably, there have been 9 recorded fatalities among the patients, while 3 individuals have survived. Solitary metastasis of calvarium region is rare, and surgical resection is effective. However, it is necessary to extend the resection range and combine with local radiotherapy to avoid local recurrence. Surgical intervention can significantly enhance the quality of life for affected patients. The prognosis of the patients mainly depends on the treatment of the primary disease and the situation of important organ dissemination and treatment.

Re-evaluation of the role of endoscopic submucosal dissection in the treatment of early gastric cancer based on additional gastrectomy results.

Endoscopic submucosal dissection (ESD) plays a pivotal role in treating early gastric cancer (EGC). Some patients require additional gastrectomy because of non-curative ESD. This study aimed to analyze the clinical factors associated with non-curative ESD and to re-evaluate the role of ESD according to its indication criteria. Altogether, 134 patients who had undergone additional gastrectomy with lymphadenectomy for non-curative ESD based on the pathological results of ESD specimens were included. Their data including pre-ESD diagnosis, reasons for requesting additional gastrectomy, and surgical outcomes were analyzed retrospectively. Of the 134 patients with EGC in the final pathology of ESD specimens, 56 underwent staging ESD for a diagnostic approach, of whom 28 were diagnosed with atypical glands and 28 with high-grade dysplasia (HGD) prior to ESD. The remaining 78 patients of the 134 were identified to have EGC and received ESD for therapy. Based on the pathological results of ESD specimens, additional gastrectomy was commissioned with non-curative ESD because of one or more causes such as deep submucosal invasion, lymphatic invasion, positive vertical margin, undifferentiated histology, positive lateral margin, and venous invasion. Regarding surgical specimens, 13 patients had lymph node metastasis (LNM) and 9 had local residual tumor; one of them had both LNM and a local residual tumor. In patients with atypical glands, 4 had LNM and 3 had a local residual tumor; one of them had both LNM and a local residual tumor, and then died of multiple organ metastasis. In patients with HGD, 4 had LNM and 1 had a local residual tumor. Additionally, 4 patients who were absolutely indicated for ESD had LNM, of whom 2 had atypical glands, and the other 2 had HGD. Similarly, in 6 patients with a local residual tumor absolutely indicated for ESD, 2 had atypical glands and 1 had HGD. Positive vertical margin, lymphatic invasion, and deep submucosal invasion were identified as independent risk factors for LNM. ESD may play diagnostic and therapeutic roles in determining the optimal treatment of EGC when the diagnosis is equivocal or insufficient in endoscopic assessments for gastric cancer screening.

6634 Dual-Mediated PTH And Osteolytic Hypercalcemia In Metastatic Endometrial Carcinoma

Abstract Disclosure: C.K. Persaud: None. D.J. Beckman: None. Background: Hypercalcemia of malignancy occurs in 20-30% of advanced stage cancer patients. Etiologies include parathyroid hormone-related peptides (PTHrP)-mediated, osteolytic metastases-mediated, overproduction of 1,25-dihydroxycholecalciferol, and rarely parathyroid hormone (PTH)-mediated. PTH-mediated hypercalcemia of malignancy is rare and occurs through ectopic PTH production or primary hyperparathyroidism. We report a rare case of both PTH-mediated and osteolytic-mediated hypercalcemia in the setting of malignancy. Clinical Case: A 57-year-old female with history of endometrial cancer and multiple solid organ metastasis, presented with two weeks of progressive poor oral intake, nausea, emesis, and right flank pain. On hospital admission, she had a serum calcium of >20.1 mg/dL (8.6-10.2), PTH of 203 pg/mL (15.0-65.0), and creatinine of 1.7 mg/dL (0.7-1.2, baseline 1.3). Non-contrasted CT chest/abdomen/pelvis noted increased size of known right adrenal metastasis, new left adrenal metastasis, periaortic lymphadenopathy, and scattered nodules in the subcutaneous tissues of the abdomen and chest, however bone metastasis were not noted. Patient’s hypercalcemia was treated with zoledronic acid, calcitonin, cinacalcet, and eventually denosumab due to difficulty controlling hypercalcemia. Additional labs obtained during evaluation included ionized calcium >2.5 nmol/L (1.12-1.32), PTHrP <2.0 pmol/L (<2.0), 1,25-dihydroxycholecalciferol <10 pg/mL (21-65). Patient’s right adrenal metastasis biopsy one month prior to admission was subsequently stained for PTH and was negative. Technetium-99m sestamibi scan was obtained for localization of parathyroid adenoma or carcinoma. The scan did not localize, however did show numerous new lytic lesions in the skull, spine, sternum, rib cage, and right humerus. Patient’s hospital course was complicated by progressively worsening renal function, anemia, and thrombocytopenia. Patient was discharged to a long-term acute rehab facility off hypercalcemia treatment with a corrected calcium of 10.0 mg/dL. Conclusion: PTH-mediated hypercalcemia is a rare cause of hypercalcemia of malignancy. PTH levels are typically low or low-normal in osteolytic mediated hypercalcemia. Generally, if PTH is elevated in hypercalcemia, an alternate etiology is not evaluated. This case highlights a rare dual-mediated hypercalcemia of malignancy. The patient’s PTH level elevation was discordant with her high degree of hypercalcemia and prolonged treatment course. She was subsequently found to have widespread bone metastases contributing to hypercalcemia. While multiple etiologies of hypercalcemia can be rare, it is important to evaluate for all contributing causes, especially with additional clinical conditions, such as malignancy. Presentation: 6/3/2024

Exceptional sustained long-term complete response to Tepotinib in a MET-amplified advanced intrahepatic biliary tract cancer failing Durvalumab plusCisplatin and Gemcitabine.

Biliary tract cancers (BTCs) are a diverse group of malignancies with varied genetic backgrounds. The prevalence of intrahepatic cholangiocarcinoma (iCC) is increasing, particularly in Western countries. Despite advancements in treatments, the prognosis for BTC remains poor. Recent molecular profiling has revealed that up to 40% of iCC cases have targetable genetic alterations. MET amplification, although rare, presents a significant target for therapy. A 25-year-old female with a history of ulcerative colitis presented with shoulder pain and a positron emission tomography-computed tomography (PET-CT) scan revealed an enlarged liver and multiple metastases. Histopathological analysis diagnosed poorly differentiated adenocarcinoma. First-line therapy with Cisplatin, Gemcitabine, and Durvalumab resulted in disease progression. Molecular profiling identified a TP53 mutation and MET amplification. Based on these findings, Tepotinib was initiated. Tepotinib treatment led to a significant reduction in tumor size and normalization of CA 19-9 levels within 2 months, achieving a complete metabolic remission lasting up to 17 months. The treatment was well tolerated with minimal side effects. MET-amplified BTCs are exceedingly rare, and evidence for targeted treatment is limited. This case demonstrates the efficacy of Tepotinib in a young patient with MET-amplified iCC, showing a long-term response and suggesting a potential new standard treatment option for this molecularly defined entity. This case also highlights the aggressive nature of MET-amplified tumors and the need for targeted second-line therapies. Tepotinib showed remarkable efficacy in treating MET-amplified intrahepatic cholangiocarcinoma, underscoring the importance of molecular profiling in BTCs and suggesting a potential new therapeutic approach for this rare cancer subtype.

Abstract A063: The role of JAK/STAT3 signaling in lung premetastatic niche formation and progression

Abstract Pancreatic ductal adenocarcinoma (PDA) is a highly deadly disease with a five-year survival rate of only 13%. Oncogenic KRAS (Kras) is a near-universal driver of PDA, and its activity is required for the formation of PDA precursor lesions, pancreatic intraepithelial neoplasia (PanIN). PanIN formation is accompanied by fibrosis and immune cell infiltration, creating a precursor tumor microenvironment that is maintained and evolves through disease progression. Our previous work has demonstrated that Kras in epithelial cells drives fibroblast activation during very early stages of pancreatic tumorigenesis and that fibroblast reprogramming occurs in a JAK/STAT3 signaling-dependent manner. Other groups have described that pancreatic cancer cells secrete specific factors to prime the liver and lung through immunomodulation and extracellular matrix remodeling, forming the premetastatic niche (PMN). Additionally, recent papers in the field have suggested a role for JAK/STAT3-reprogramming in the formation of the PMN during pancreatic tumorigenesis. Presently, it remains to be elucidated at what stage of PDA tumorigenesis the PMN is initiated, as well as the mechanisms underlying formation. In a pilot experiment, we induced pancreas specific Kras until mice had PanIN lesions but no overt malignancy. We then harvest the pancreas and lung for single cell RNA sequencing. Here, results showed that when Kras is expressed within the pancreas of a mouse, fibroblasts are reprogrammed within the lung, prior to pancreatic tumor formation. Additionally, data indicates JAK/STAT3 signaling activation present within these fibroblasts. We also used multiple lung metastasis models, both spontaneous and tail vein injection, to show persistence of this reprogramming. This suggests that pancreatic Kras expression can systemically reprogram fibroblasts to form a PMN more capable of seeding cancer cells. Our in vitro studies have showed similar results as lung fibroblasts treated with Kras ON conditioned media show increased pSTAT3. Furthermore, using multiplex ELISA on iKras conditioned media, we have identified multiple promising secreted factor hits that may play a role in lung fibroblast reprogramming. Ongoing studies aim to define the mechanism of pulmonary fibroblast reprogramming in the context of the PMN and to assess the role of pSTAT3+ fibroblast reprogramming on establishment of pulmonary metastases. Citation Format: Emily Lasse Opsahl, Carlos E Espinoza, Katelyn L Donahue, Ahmed M Elhossiny, Padma Kadiyala, Allison C Bischoff, Mary Poggi, Yaqing Zhang, Jiaqi Shi, Timothy Frankel, Marina Pasca di Magliano. The role of JAK/STAT3 signaling in lung premetastatic niche formation and progression [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A063.

Complete Response of an Iraqi Patient with Multiple Liver Metastasis, Colon Cancer and Deep Vein Thrombosis to XELOX/Bevacizumab Treatment

Background: The incidence of colon cancer is rising globally, and several therapeutic techniques, such as surgery, radiation, and systemic therapy, are used to control this illness. Patients with initially treatable metastatic colorectal cancer and unresectable metastases receive preoperative chemotherapy. In patients with rapidly progressing cancer, this strategy aims to shrink the tumor, manage any micro-metastases, and avoid liver surgery. Case presentation: We present a rare case of an Iraqi patient with metastatic colon cancer and an initially unresectable liver metastasis. The patient initially experienced a partial response to chemotherapy with capecitabine, oxaliplatin (XELOX), and Bevacizumab, but after a few days, we observed deep venous thrombosis (DVT). We stopped the oxaliplatin and administered Capecitabine with bevacizumab as a chemotherapy treatment, observing no adverse effects during the therapy period and achieving a complete response with Capecitabine and bevacizumab. Conclusions: The full response in the liver and colon after treatment, which reduced the patients' treatment burden, was the case's unique result. Additionally, this study highlights deep vein thrombosis as a critical problem that can arise with the use of oxaliplatin.

798. FEASIBILITY AND EFFICACY OF CISPLATIN, PACLITAXEL AND IMMUNE CHECKPOINT INHIBITORS AS CONVERSION THERAPY FOR LOCOREGIONALLY UNRESECTABLE ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background Induction therapy followed by conversion surgery is potentially curative for locoregionally unresectable esophageal squamous cell carcinoma (ESCC). However, the optimal induction treatment strategy is unclear. The study aimed to evaluate the feasibility and efficacy of cisplatin, paclitaxel and immune checkpoint inhibitors as conversion therapy for locoregionally unresectable ESCC. Methods Clinicopathological variables of cT4b ESCC patients who received neoadjuvant chemoimmunotherapy were retrieved from the prospective database of the Surgical Esophageal Cancer Patient Registry in West China Hospital, Sichuan University. Enhanced computed tomography, ultrasonography and bronchoscopy were routinely used for the diagnosis. The treatment protocol of neoadjuvant chemoimmunotherapy included 2 cycles of immunotherapy plus chemotherapy with the interval of 3 weeks among each cycle. All patients received 2 cycles of Pembrolizumab (200 mg, D1), Sintilimab (200 mg, D1), Tislelizumab (200 mg, D1) or Camrelizumab (200 mg, D1) intravenously. Concurrently all patients received 2 cycles of cisplatin (75 mg/m2 of body-surface area, D1) and paclitaxel (175 mg/m2 body-surface area, D1) intravenously. The perioperative parameters and short-term surgical outcomes were presented (Table). Results Between January 2020 and December 2022, a total of 317 ESCC patients who underwent neoadjuvant chemoimmunotherapy followed by surgery were screened. Twenty cT4b patients with middle or upper thoracic ESCC were finally enrolled in this study. Pretreatment tumor invades the trachea (4, 20%), left main bronchus (16, 80%), and aorta (6, 30%), respectively. All the patients were successfully performed by McKeown minimally invasive esophagectomy except for one patient conversion to thoracotomy. R0 resection was achieved in 15 patients, 4 patients underwent R1 resection and 1 patient underwent R2 resection. Mean operation duration was 290.4 ± 57.5 min. Mean estimated blood loss was 94.4 ± 108.8 ml. Three patients had postoperative pneumonia, two patients had postoperative pleural effusion and one patient had postoperative recurrent laryngeal nerve paralysis. No patient had postoperative anastomotic leak. No postoperative reoperation was needed and there was no perioperative mortality. Mean length of hospital stay was 10.9±1.4 days. 90-day mortality occurred in one patient with postoperative multiple systemic metastasis. Fifteen patients are alive with a median follow up of 18 months. One patient died with regional lymph node recurrence and three patients died with hematogenous dissemination. Conclusion Multimodal treatment strategy combining immunotherapy and chemotherapy may convert unresectable tumors into potentially operable ones, and achieved favorable survival. Longer follow-up and larger sample size are needed to verify our preliminary results.

2241: National intercomparison of radiosurgery treatment planning for multiple brain metastasis

2241: National intercomparison of radiosurgery treatment planning for multiple brain metastasis

Metastasis of malignant melanoma to urinary tract: a case report

IntroductionMetastasis of malignant melanoma to urinary tract is reported to be rare. According to retrospective analysis of a single center study, improvement of overall survival was observed in patients with metastasis to the gastrointestinal tract that had undergone metastasectomy with curative intent. However, there is no significant evidence regarding resection for metastasis to urinary tract.Case presentationCase 1: an 86-year-old Japanese man was diagnosed with a small bladder tumor by computed tomography scan during post operative follow-up of malignant melanoma in the choroid of the left eye. Cystoscopy revealed black, nonpapillary tumors, suggesting metastatic malignant melanoma. Because no apparent invasive growth to muscle layer was observed by magnetic resonance imaging, transurethral resection was performed. Pathological appearance was compatible with metastatic malignant melanoma. No recurrence in urinary tract was observed; however, multiple liver metastasis was diagnosed at 3 months after surgery. Case 2: a 57-year-old Japanese man was diagnosed with right hydronephrosis due to ureteral tumor. He had a past history of subungual malignant melanoma to the left thumb 2 years prior to his visit. Right nephroureterectomy was performed, and pathological evaluation revealed metastatic malignant melanoma. He revisited 2 years later due to dysuria, and a large bladder tumor was revealed by ultrasound. Cystoscopy showed black-colored nonpapillary tumor, suggesting malignant melanoma. Total cystectomy was recommended; however, the patient withheld consent. Therefore, we performed transurethral resection. The resulting pathological finding was compatible with metastatic malignant melanoma without invasion to muscle layer. He remained free from local recurrence and metastasis for 22 years after surgery.ConclusionWe successfully performed metastasectomy for bladder and ureteral metastases without recurrence in the urinary tract. Long recurrence-free survival was observed in case 2. Complete resection for metastasis of malignant melanoma may have the potential to improve survival.

Predictive Factors for Long-Term Disease Control in Systemic Treatment-Naïve Oligorecurrent Renal Cell Carcinoma Treated with Up-Front Stereotactic Ablative Radiotherapy (SABR).

Stereotactic ablative radiotherapy (SABR) is emerging as a potential local treatment option for oligometastatic RCC. This study aims to evaluate the efficacy of SABR in patients with oligorecurrent RCC. A total of 50 patients with histologically confirmed RCC underwent SABR for oligorecurrence between 2006 and 2022. Eligible patients had up to five extracranial metastases and were systemic treatment-naïve at the time of irradiation. The primary endpoints of the analysis were overall survival (OS), local control (LC), distant metastasis-free survival (DMFS), and time to systemic therapy initiation. The median OS was not reached, with 1- and 3-year OS rates of 93.8% and 77.5%, respectively. LC rates at one and three years were 95.8% and 86.5%, respectively. The median time to systemic therapy initiation was 63.8 months, and the median DMFS was 17.9 months, with one- and three-year rates of 63.4% and 36.6%, respectively. Multiple metastases were a negative predictive factor for DMFS (HR 2.39, p = 0.023), whereas lung metastases were associated with a more favorable outcome (HR 0.38, p = 0.011). SABR offers a valuable treatment option for oligometastatic RCC, demonstrating significant potential for achieving long-term disease control and delaying the need for systemic therapy.

Brain Metastases in Differentiated Thyroid Cancer: Clinical Presentation, Diagnosis, and Management.

Background: Brain metastases (BM) are the most common intracranial neoplasms in adults and are a significant cause of morbidity and mortality. The brain is an unusual site for distant metastases of thyroid cancer; indeed, the most common sites are lungs and bones. In this narrative review, we discuss about the clinical characteristics, diagnosis, and treatment options for patients with BM from differentiated thyroid cancer (DTC). Summary: BM can be discovered before initial therapy due to symptoms, but in most patients, BM is diagnosed during follow-up because of imaging performed before starting tyrosine kinase inhibitors (TKI) or due to the onset of neurological symptoms. Older male patients with follicular thyroid cancer (FTC), poorly differentiated thyroid cancer (PDTC), and distant metastases may have an increased risk of developing BM. The gold standard for detection of BM is magnetic resonance imaging with contrast agent administration, which is superior to contrast-enhanced computed tomography. The treatment strategies for patients with BM from DTC remain controversial. Patients with poor performance status are candidates for palliative and supportive care. Neurosurgery is usually reserved for cases where symptoms persist despite medical treatment, especially in patients with favorable prognostic factors and larger lesions. It should also be considered for patients with a single BM in a surgically accessible location, particularly if the primary disease is controlled without other systemic metastases. Additionally, stereotactic radiosurgery (SRS) may be the preferred option for treating small lesions, especially those in inaccessible areas of the brain or when surgery is not advisable. Whole brain radiotherapy is less frequently used in treating these patients due to its potential side effects and the debated effectiveness. Therefore, it is typically reserved for cases involving multiple BM that are too large for SRS. TKIs are effective in patients with progressive radioiodine-refractory thyroid cancer and multiple metastases. Conclusions: Although routine screening for BM is not recommended, older male patients with FTC or PDTC and distant metastases may be at higher risk and should be carefully evaluated for BM. According to current data, patients who are suitable for neurosurgery seem to have the highest survival benefit, while SRS may be appropriate for selected patient.

Outcomes and Prognostic Factors of Patients with Unresectable or Metastatic Esophageal Squamous Cell Carcinoma Undergoing Immunotherapy- Versus Chemotherapy-Based Regimens: Systematic Review and Pooled Analyses.

Immunotherapy-based regimens (IMT) versus cytotoxic chemotherapy (CHT) improved overall survival (OS) of patients with unresectable or metastatic esophageal squamous cell carcinoma (mESCC), but the role of prognostic variables is unclear. The study aims to explore the interaction of prognostic factors with survival after IMT or CHT. A systematic review was performed to select trials comparing IMT and CHT regimens in mESCC patients. A meta-analysis of upfront IMT + CHT vs. CHT trials evaluated the overall effect size and heterogeneity between studies. In view of the expected differences between chemotherapy and immunotherapy on the survival curve, to better explore the effect of any prognostic variables on OS, before and after progression, the treatment arms were evaluated as independent cohorts, and ten baseline variables were extracted and assessed by linear regression. Fourteen trials were identified. Seven studies compared upfront CHT + IMT vs. CHT documenting longer OS for CHT + IMT (HR 0.69, CI 0.65-0.72), without heterogeneity (Q = 1.43, p value = 0.968) or differences in the most represented subgroups. Twenty-nine study cohorts were selected from the 14 trials. Median OS and PPS, but not PFS, were significantly increased after IMT compared with CHT. The analysis of baseline variables after CHT documented a favorable prognostic effect for advanced age (β = 0.768, p value = 0.016), involvement of 0-1 metastasis sites (β = 0.943, p value = 0.005), and absence of previous radiation therapy (β = - 0.939, p value = 0.006), while none of them influenced prognosis after IMT. The introduction of upfront IMT prolonged mESCC patients OS, mostly improving the outcomes of young patients, with multiple metastasis sites and without previous radiotherapy.

Jejunal sarcomatoid carcinoma: A case report and review of literature

BACKGROUND Sarcomatoid carcinoma (SCA) of the jejunum is a rare and aggressive neoplasm affecting the smooth muscle cells of the jejunum. This study presents a recent case of jejunal SCA, detailing its diagnosis and treatment, thereby providing a reference for clinical practice. CASE SUMMARY A 65-year-old male presented to Yichang Central People's Hospital with a chief complaint of hemorrhoids. A computed tomography (CT) scan incidentally revealed multiple abnormal signals in the liver. Subsequent positron emission tomography/CT at Wuhan Union Hospital indicated malignant tumor progression, with a primary duodenal tumor and multiple metastases in the upper left abdomen. Intraoperatively, a large tumor was identified on the omentum. Histopathological and immunohistochemical analyses of the resected specimen confirmed the diagnosis of jejunal SCA. The patient received a combination therapy of sintilimab, nanoparticle albumin-bound paclitaxel, and anlotinib. Follow-up imaging demonstrated significant reduction of hepatic and peritoneal lesions. The patient has remained stable for over one year postoperatively. CONCLUSION This case suggests that chemotherapy, immunotherapy, plus targeted therapy may represent an optimal treatment for intestinal SCA, meriting further investigation.