Resection Of Thymoma Research Articles

Long term outcomes from the early days of minimally invasive thymoma surgery for Myasthenia Gravis patients: a follow-up of 19 years.

Long-term survival outcomes are crucial for accurately determining the effectiveness of treatment in an indolent disease like thymoma. We aimed to analyze the clinical findings in terms of survival and relapse patterns with a median follow up of 105 months (8.7 years) in patients with thymoma and myasthenia gravis who underwent minimally invasive surgery between 2002 and 2015. A total of 59 pathologically confirmed Masaoka Stage I and II thymoma patients with Myasthenia Gravis (MG) who underwent minimally invasive thymoma resection were included in this study. Primary aim of this study is to evaluate recurrences, overall and disease free survival in patients with a thymoma and MG in the long run. We also aimed to study the changes in Myasthenia Gravis medication during the follow-up. The mean age of the patients was 47.6 +/13.5 years. Seventeen patients were at Masaoka Stage I and 42 were at Masaoka Stage II. The median follow-up time was 105 months. The mean size of the tumor was 3.6 cm +/16.2 cm. Twenty-one patients (35%) received adjuvant radiotherapy. There was no postoperative mortality and median length of hospital stay was 4 days. Two patients developed recurrences both presented with pleural metastases. Eight patients died because of non-oncologic pathologies. 10-year disease free survival and overall survival rates were calculated to 96.6% and 86.4% respectively. The 10-year survival analysis and current myasthenic status of stage I-II thymoma patients with myasthenia gravis who underwent minimally invasive surgery demonstrate that these procedures are both safe and effective.

Thoracoscopic minimally invasive surgical treatment with the same incisions in a patient with uremia complicated with large thymoma and right upper lobe lung cancer: a case report

A 41 year old female with stage 5 chronic kidney disease undergoing hemodialysis was admitted to the hospital. Chest CT scan revealed a large mass lesion of approximately 6.0 × 3.5x4.9 cm in size in the anterior superior mediastinum and a ground glass nodule in the upper lobe of the right lung, which increased in size from 9 × 7 mm 1 year and 9 months ago to 11mmx9mm before surgery. We designed a localization method to accurately locate the pulmonary nodule and successfully performed thoracoscopic minimally invasive resection of both thymoma and lung cancer through a subxiphoid approach with the same incision for this patient. With the support of perioperative hemodialysis, the patient's outcome is good. The pathological diagnosis of the anterior mediastinal mass is thymoma (b1 type), and the pathological diagnosis of the right upper lobe nodule is invasive lung adenocarcinoma (acinar type). This report describes the diagnosis and treatment process of the case.

Good syndrome combined with multiple microbial pulmonary infections: case report and review of the literature.

Good syndrome (GS), a rare acquired immunodeficiency disorder characterized by thymoma and hypogammaglobulinemia, predisposes individuals to recurrent infections. This study reports a case of a 37-year-old male GS with multiple pulmonary infections and reviews relevant literature. The patient, with a history of thymoma resection, experienced multiple hospitalizations due to lung infections and neutropenia. The alveolar lavage fluid was detected by macro-genomic sequencing (NGS) to detect multiple pathogens, and targeted anti-infective and immunity-enhancing treatments led to improved symptoms and normal neutrophil counts. A literature review of 98 case reports from 2000 to 2023 was conducted, summarizing the associated diseases and pathogens in GS patients. Regular immunoglobulin monitoring in thymoma patients is essential for early GS diagnosis. When empirical antimicrobial therapy fails, mNGS for pathogen detection and targeted therapy are crucial, and regular IVIG injections can reduce infection rates in GS patients.

Robotic-assisted extended thymectomy for large resectable thymoma: 21 years’ experience

ObjectiveThis study aims to evaluate the perioperative and midterm oncological outcomes of robotic-assisted thoracic surgery extended thymectomy for patients with large resectable thymomas compared with small thymomas. MethodsThis retrospective single-center study included 204 patients with thymomas who underwent robotic-assisted thoracic surgery extended thymectomy between January 2003 and February 2024. Patients were divided into 2 groups based on the thymoma size (5-cm threshold). ResultsThe study comprised 114 patients (55.9%) in the small thymoma group and 90 patients (44.1%) in the large thymoma group. No significant differences were found between the groups regarding gender, age, proportion of elderly patients, or pathologic high-risk classifications. Apart from a longer operative time (P = .009) in the large thymoma group, no differences were observed between the 2 groups regarding surgical parameters and postoperative outcomes. No deaths occurred within 30 days in either group. During a median follow-up of 61.0 months (95% CI, 48.96-73.04), 4 patients experienced recurrence (1.96%). No significant differences in the 5-year overall survival (P = .25) or recurrence-free survival (P = .43) were observed between groups. ConclusionsRobotic-assisted thoracic surgery extended thymectomy is technically feasible, safe, and effective for treating large resectable thymomas. Moreover, midterm outcomes for patients with completely resected large thymomas were comparable to those with small thymomas during a median follow-up period of up to 5 years.

Thymoma resection and myasthenia gravis: what is the neurological outcome in patients older than 65years?

To increase the neurological results in patients older than 65years with myasthenia gravis after thymectomy, we retrospectively analysed this outcome in a large bicentric cohort of patients with myasthenia gravis (MG)years, for which surgery was indicated for a concurrent thymoma. From 1/2000 to 2/2022, 502 patients underwent thymectomy for thymic epithelial tumours (TETs) in two high-volume Institutions (167aged more than 65years). Among them, 66 patients were affected by TET and MG, representing our final study group. The mean age for MG onset was 68.3 ± 6years.At surgery, the Osserman score 2 was the most diffuse in our cohort (43, 65.1%), followed by 1 (20, 30.3%). In 11 cases, the MG diagnosis coincided with thymoma diagnosis. In the other cases, the interval between MG diagnosis and surgery was 1.7years ± 1.9. The most common surgical approach was sternotomy (41,62.1%), followed by RATS (14,21.2%). The most frequent TNM stage was T1N0 (75.7%) and most patients had WHO type-B tumour. After radical thymectomy, 58 patients (88%) reported a significant neurological improvement. According to MGFA-PIS, after surgery we had 4 (6%) complete stable remission, 11 (16.7%) pharmacological remission, 43 (65.2%) minimal manifestation, 2 (3%) worsening/death for MG, and 5 (7.6%) unchanged. No association was found between neurological outcome and age of MG onset, kind of pharmacological therapy before surgery, surgical approach (sternotomy vs others), tumour dimension, the ITMIG stage and the preoperative Osserman score. For MG and thymoma-afftected patients over 65years, thymectomy seems to be an effective treatment to improve neurological symptoms. We suggest to set up clinical trials to explore the neurological efficacy of mini-invasive thymectomy in clinically selected MG patients aged over 65years.

Early stage thymoma and the surgical extent paradigm

The recommended treatment for early stage thymoma without myasthenia gravis is complete thymectomy (CT). Limited thymectomy (LT) (simply resecting the thymoma with safe surgical margins) is gaining popularity. In this study, we compared the surgical and oncological results of complete and limited thymectomy in non-myasthenic patients with early stage thymoma. Non-myasthenic, Masaoka stage I–II, 86 patients who underwent surgical resection for thymoma were included in the study. Complete thymectomy (n:44) included patients who had resection of the thymoma together with the entire thymus and limited thymectomy (n:42) included patients who had resection of the thymoma without remaining thymus. The surgical approach, tumor size, histological type, pathological stage, adjuvant therapy, complications, postop myasthenia gravis, recurrence and death were recorded and compared between groups. Complete thymectomy group had more WHO type B1-3 tumors, more complications and more deaths than patients in the limited thymectomy group (p = 0.03, 0.018 and 0.023 respectively). Although statistically not significant CT group had more recurrences than LT group (11.4%/4.8%, p = 0.43). The 10-year freedom from recurrence (FFR) rate in the CT group was 84.8% and in the LT group ıt was 97.6%, the difference was not statistically significant (p = 0.15). None of the factors including surgical extent analysed with univariate and multivariate analysis had a significant effect on FFR. Limited thymectomy may be a good treatment option for non-myasthenic early stage thymoma patients but randomized controlled trials with long follow-up periods, ideally comparing patients operated with minimally invasive surgery are necessary.

Long-term follow-up of non-myasthenic patients with early-stage thymoma who underwent extended thymectomy or limited resection

BackgroudThe standard resection for early-stage thymoma is total thymectomy and complete tumour excision with or without myasthenia gravis but the optimal surgery mode for patients with early-stage non-myasthenic thymoma is debatable. This study analysed the oncological outcomes for non-myasthenic patients with early-stage thymoma treated by thymectomy or limited resection in the long term. MethodsPatients who had resections of thymic neoplasms at Taipei Veteran General Hospital, Taiwan between December 1997 and March 2013 were recruited, exclusive of those combined clinical evidence of myasthenia gravis were reviewed. A total of 113 patients were retrospectively reviewed with pathologic early stage (Masaoka stage I and II) thymoma who underwent limited resection or extended thymectomy to compare their long-term oncologic and surgical outcomes. ResultsThe median observation time was 134.1 months [interquartile range (IQR) 90.7–176.1 months]. In our cohort, 52 patients underwent extended thymectomy and 61 patients underwent limited resection. Shorter duration of surgery (p < 0.001) and length of stay (p = 0.006) were demonstrated in limited resection group. Six patients experienced thymoma recurrence, two of which had combined myasthenia gravis development after recurrence. There was no significant difference (p = 0.851) in freedom-from-recurrence, with similar 10-year freedom-from-recurrence rates between the limited resection group (96.2 %) and the thymectomy group (93.2 %). Tumour-related survival was also not significantly different between groups (p = 0.726).result ConclusionPatients with early-stage non-myasthenic thymoma who underwent limited resection without complete excision of the thymus achieved similar oncologic outcomes during the long-term follow-up and better peri-operative results compared to those who underwent thymectomy.

Recommendations for Post-Operative RadioTherapy After Complete Resection of Thymoma—a French DELPHI Consensus Initiative

IntroductionThymomas are rare intrathoracic malignancies that can relapse after surgery. Whether or not Post-Operative RadioTherapy (PORT) should be delivered after surgery remains a major issue. RADIORYTHMIC is an ongoing, multicenter, randomized phase 3 trial addressing this question in patients with completely R0 resected Masaoka-Koga stage IIb/III thymoma. Experts in the field met to develop recommendations for PORT. MethodsA scientific committee from the RYTHMIC network identified key issues regarding the modalities of PORT in completely resected thymoma. A DELPHI method was used to question 24 national experts, with 115 questions regarding the following: (1) imaging techniques, (2) clinical target volume (CTV) and margins, (3) dose constraints to organs at risk, (4) dose and fractionation, and (5) follow-up and records. Consensus was defined when opinions reached more than or equal to 80% agreement. ResultsWe established the following recommendations: preoperative contrast-enhanced computed tomography (CT) scan is recommended (94% agreement); optimization of radiation delivery includes either a four-dimensional CT-based planning (82% agreement), a breath-holding inspiration breath-hold–based planning, or daily control CT imaging (81% agreement); imaging fusion based on cardiovascular structures of preoperative and planning CT scan is recommended (82% agreement); right coronary and left anterior descending coronary arteries should be delineated as cardiac substructures (88% agreement); rotational RCMI/volumetric modulated arc therapy is recommended (88% agreement); total dose is 50 Gy (81% agreement) with 1.8 to 2 Gy per fraction (94% agreement); cardiac evaluation and follow-up for patients with history of cardiovascular disease are recommended (88% agreement) with electrocardiogram and evaluation of left ventricular ejection fraction at 5 years and 10 years. ConclusionThis is the first consensus for PORT in thymoma. Implementation will help to harmonize practices.

Relapsing Anti-GAD65-Associated Encephalitis Responsive to Thymoma Resection, Radiation, and Immunomodulatory Therapy.

Herein we describe a case of relapsing anti-GAD65-associated encephalitis which was responsive to the combination of thymoma resection, external beam radiotherapy, and immunomodulatory therapy. The case illustrates the value of remaining vigilant for the possibility of paraneoplastic syndromes in the context of anti-GAD65 antibodies and thymoma. It also illustrates that tumor-directed therapies may offer additional benefit beyond immunomodulatory therapy alone.

Clinicopathological predictors of postoperative long-term myasthenic status in resected thymoma with myasthenia gravis.

Surgical patients with thymoma and myasthenia gravis (MG) must have their MG status and oncological outcomes critically monitored. We aimed to identify clinicopathological predictors of the postoperative MG status. We conducted a retrospective review of 40 consecutive surgical patients with MG-related thymomas between 2002 and 2020. The quantitative myasthenia gravis score (QMGS) and Myasthenia Gravis Foundation of America post-intervention status (MGFA-PIS) were used to evaluate postoperative MG status. All patients underwent extended total thymectomy. The most common WHO type was type B2 (32%), while 65% of patients had type B1-B3 and 35% had type A-AB thymomas. Eleven patients (28%) achieved controlled MG status in MGFA-PIS 6months after surgery. This controlled status was observed more frequently in type A-AB than in B1-B3 (57% vs. 12%, p = 0.007). In a multivariate analysis, WHO type (A-AB or B1-B3) was an independent predictor of worsening episodes of MG based on the QMGS (Type B1-B3, hazard ratio: 3.23, 95% confidence interval: 1.12-9.25). At the last follow-up, 23 patients (58%) achieved controlled MG status. The 5-year overall survival rate of all patients was 93.7%. The WHO type of thymoma is an informative predictor of postoperative MG status in patients with MG-related thymoma.

Good Syndrome: Cytomegalovirus retinitis case challenge.

To describe cytomegalovirus retinitis in a patient with Good syndrome (hypogammaglobulinemia and thymoma), ocular progression despite treatment, and fatal outcome. A 71-year-old woman with unilateral panuveitis of unknown cause and a history of thymoma resection was referred to our clinic. Visual acuity (VA) was 20/100 in her right eye (OD) and light perception in her left eye (OS). In slit-lamp examination, OD had inferior fine pigmented keratic precipitates, 2+ anterior chamber (AC) cells, cataract, and 2+ vitreous cells, no fundus detail, and normal ocular ultrasound. OS presented a white cataract, chronic hypotony, and increased choroidal thickness with calcifications. Laboratory evaluations were normal or negative for common causes of infection and inflammation. Prednisolone acetate eye drops were started, with improvement of AC inflammation. Cataract surgery was performed, reaching VA of 20/30. Two years later, VA had decreased and 2+ vitritis and retinitis were found. On clinical suspicion of masquerade syndrome, a vitrectomy biopsy was performed; pathology reported no data on ocular lymphoma. Leukopenia and lymphopenia were found: immunoglobulin levels, CD4 count, and viral load revealed systemic immunosuppression. The aqueous tap was positive for cytomegalovirus. Oral valganciclovir and intravitreal ganciclovir were initiated. In a patient with previous resection of thymoma and hypogammaglobulinemia, final diagnosis was Good syndrome, with CMVR being secondary to immunosuppression. Despite treatment, CMVR progressed and systemic deterioration resulted in mortal outcome. Good syndrome is an extremely rare disease and association with CMVR is uncommon. To our knowledge, only 14 cases exist in the literature.

Independent risk factors for in-hospital outcome of myasthenic crisis: a prospective cohort study.

Myasthenic crisis (MC) is a life-threatening condition for myasthenia gravis (MG). Therapeutic plasma exchange (TPE) and intravenous immunoglobulin (IVIg) efficaciously treat patients with MC. However, not every MC responds well to rescue therapies, and the determinants for outcome with the evidence from prospective cohorts are still lacking. To explore the risk factors for in-hospital outcomes in patients with MC. Using a national neuromuscular center-based cohort of MG with prospective follow-ups from the crisis to the post-crisis phase, we finally included 90 MC episodes from 76 independent patients who received a standard regimen of rescue therapies. The mean admission age was 52.89 ± 15.72 years. With a female predominance of 63.16% (48/76) and a high proportion of thymoma-associated MG (TMG) of 63.16% (48/76), the overall in-hospital mortality was 2.63% (2/76) and the average duration for mechanical ventilation (MV) use was 17.09 ± 13.36 days (0-53 days). In contrast to the patients with anti-acetylcholine receptor (AChR) antibodies, muscle-specific tyrosine kinase (MuSK)-associated MC exhibited a shorter MV support (5.20 ± 5.07 versus 17.40 ± 13.24 days, p = 0.023), length of intensive care units (ICU) stay (6.00 ± 4.64 versus 19.16 ± 17.54 days, p = 0.046), and hospital stay (16.00 ± 4.12 versus 34.43 ± 20.48 days, p = 0.011). Thymoma [odds ratio (OR): 0.200, 95% confidence interval (CI): 0.058-0.687, p = 0.011], partial pressure of carbon dioxide (PCO2) in blood gas before MV (OR: 1.238, 95% CI: 1.015-1.510, p = 0.035), and pneumonia (OR: 0.204, 95% CI: 0.049-0.841, p = 0.028) were identified as independent risk factors for prolonged MV use. TMG patients with thymoma burden exhibited a notable longer MV use (22.08 ± 17.54 versus 8.88 ± 6.79 days, p = 0.001), a prolonged hospital stay (40.40 ± 26.13 versus 23.67 ± 13.83 days, p = 0.009) compared with non-TMG. Even with complete thymoma resection (R0), TMG exhibited an unfavorable outcome versus non-TMG. With timely rescue therapies and prospective follow-ups, the in-hospital outcome of MCs was substantially improved. Thymoma, PCO2 in blood gas before MV, and pneumonia were identified as independent risk factors for prolonged MV use.

Postoperative radiotherapy for completely resected thymoma and thymic carcinoma: A systematic review and meta-analysis.

The role of postoperative radiotherapy (PORT) after complete tumor resection in patients with thymoma or thymic carcinoma remains controversial. We performed a meta-analysis to identify groups that would benefit from PORT. Multiple scientific databases were systematically searched for studies comparing overall survival (OS) and/or disease-free survival (DFS) between PORT and surgery alone in patients with completely resected thymomas or thymic carcinomas until April 10, 2024. A random-effects model was used for the statistical analysis. A total of 31 studies with 10543 patients were included (17 studies involving 4763 patients with thymoma, seven studies involving 1045 patients with thymic carcinoma, and seven studies involving 4735 patients with mixed histological types). Notably, PORT significantly prolonged OS (hazard ratio [HR] = 0.73, 95% confidence interval [CI]: 0.59-0.91) and DFS (HR = 0.62, 95% CI: 0.43-0.89). Similar results were also observed when the multivariate-adjusted HRs were used as the measure of effect (OS: HR = 0.60, 95% CI: 0.43-0.83; DFS: HR = 0.48, 95% CI: 0.29-0.79). In subgroup analyses, PORT was associated with a longer OS and DFS for thymoma (HR = 0.73, 95% CI: 0.56-0.96 and HR = 0.65, 95% CI: 0.46-0.93), thymic carcinoma (HR = 0.72, 95% CI: 0.49-1.07 and HR = 0.38, 95% CI: 0.19-0.77), and stage 3-4 disease (HR = 0.50, 95% CI: 0.34-0.74 and HR = 0.44, 95% CI: 0.27-0.70), but not for stage 2 disease (HR = 0.81, 95% CI: 0.55-1.19 and HR = 0.97, 95% CI: 0.51-1.83). PORT is likely to improve OS and DFS in patients with completely resected stage 3-4 thymoma or thymic carcinoma; however, the value of PORT for stage 2 disease requires further evaluation in large-scale studies.

Evaluation of the effect of PET/CT Fluorodeoxyglucose inclusion on mortality and survival in operated thymoma patients.

In recent years, the use of fluorodeoxyglucose PET-computed tomography (PET-CT) has become widespread to evaluate the diagnosis, metabolism, stage and distant metastases of thymoma. In this study, it was aimed to investigate the connection of malignancy potential, survival and maximum standardized uptake value (SUV max ) measured by PET-CT before surgery according to the histological classification of the WHO in patients operated for thymoma. In addition, the predictive value of the Glasgow prognostic score (GPS) generated by C-reactive protein (CRP) and albumin values on recurrence and survival was investigated and its potential as a prognostic biomarker was evaluated. Forty-five patients who underwent surgical resection for thymoma and were examined with PET-CT in the preoperative period between January 2010 and January 2022 were included in the study. The relationship between WHO histological classification, tumor size and SUV max values on PET-CT according to TNM classification of retrospectively analyzed corticoafferents were evaluated. Preoperative albumin and CRP values were used to determine GPS. The cutoff value for SUV max was found to be 5.65 in the patients and the overall survival rate of low-risk (<5.65) and high-risk (>5.65) patients was compared according to the SUV max threshold value (5.65) and found to be statistically significant. In addition, the power of PET/CT SUV max value to predict mortality (according to receiver operating characteristics analysis) was statistically significant ( P = 0.048). Survival expectancy was 127.6 months in patients with mild GPS (O points), 96.7 months in patients with moderate GPS (1 point), and 25.9 months in patients with severe GPS (2 points). PET/CT SUV max values can be used to predict histological sub-type in thymoma patients, and preoperative SUV max and GPS are parameters that can provide information about survival times and mortality in thymoma patients.

Germinal centers are associated with postthymectomy myasthenia gravis in patients with thymoma.

Germinal centers (GCs) can be observed in the thymic tissues of patients with thymoma-associated myasthenia gravis (MG). Although an association between thymic GCs and MG has been suggested, it is unknown whether the presence of GCs could predict the development of MG after the resection of thymoma, known as postthymectomy MG. We conducted a retrospective analysis of previously nonmyasthenic patients who underwent surgical removal of the thymoma. All available thymic tissue slides were rereviewed by a pathologist to assess for GCs. Patients were classified into GC-positive and GC-negative groups based on the presence of GCs. The incidence of postthymectomy MG was compared between the two groups, and the risk factors for postthymectomy MG were assessed. Of the 196 previously nonmyasthenic patients who underwent thymoma resection, 21 were GC-positive, whereas 175 were GC-negative. Postthymectomy MG developed in 11 (5.6%) patients and showed a higher incidence in the GC-positive group than in the GC-negative group (33.3% vs. 2.3%, p < 0.001). No postoperative radiotherapy and the presence of GCs were risk factors for postthymectomy MG in the univariate analysis. In multivariate analysis, invasive thymoma (hazard ratio [HR] = 9.835, 95% confidence interval [CI] = 1.358-105.372), postoperative radiotherapy (HR = 0.160, 95% CI = 0.029-0.893), and presence of GCs (HR = 15.834, 95% CI = 3.742-67.000) were significantly associated with postthymectomy MG. Thymic GCs may be a significant risk factor for postthymectomy MG. Even in patients with thymoma who do not show clinical symptoms of MG, postthymectomy MG should be considered, especially if thymic GCs are observed.

Resection of a micronodular thymoma with lymphoid stroma achieved by robot-assisted thoracic surgery (RATS): a case report

Resection of a micronodular thymoma with lymphoid stroma achieved by robot-assisted thoracic surgery (RATS): a case report

Prognostic factors in patients with thymoma who underwent surgery

PurposeThymoma is the most common primary tumor in the anterior mediastinum. The prognostic factors of patients with thymoma still need to be clarified. In this study, we aimed to investigate the prognostic factors of patients with thymoma who received radical resection and establish the nomogram to predict the prognosis of these patients.Materials and methodsPatients who underwent radical resection for thymoma with complete follow-up data between 2005 and 2021 were enrolled. Their clinicopathological characteristics and treatment methods were retrospectively analyzed. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method and compared by the log-rank test. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify the independent prognostic factors. According to the results of the univariate analysis in the Cox regression model, the predictive nomograms were created.ResultsA total of 137 patients with thymoma were enrolled. With a median follow-up of 52 months, the 5-year and 10-year PFS rates were 79.5% and 68.1%, respectively. The 5-year and 10-year OS rates were 88.4% and 73.1%, respectively. Smoking status (P = 0.022) and tumor size (P = 0.039) were identified as independent prognostic factors for PFS. Multivariate analysis showed that a high level of neutrophils (P = 0.040) was independently associated with OS. The nomogram showed that the World Health Organization (WHO) histological classification contributed more to the risk of recurrence than other factors. Neutrophil count was the most important predictor of OS in patients with thymoma.ConclusionSmoking status and tumor size are risk factors for PFS in patients with thymoma. A high level of neutrophils is an independent prognostic factor for OS. The nomograms developed in this study accurately predict PFS and OS rates at 5 and 10 years in patients with thymoma based on individual characteristics.

Lobulated tumor contour as a predictor of preoperative tumor invasion of the lung or pericardium in thymoma patients.

Preoperative investigations to detect invasion to neighboring organs are important for deciding on the most appropriate surgical approach for thymoma. We evaluated preoperative computed tomography (CT) findings in thymoma patients to identify the CT features associated with tumor invasion. Clinicopathologic information on 193 patients who underwent surgical resection for thymoma at Chiba University Hospital between 2002 and 2016 was collected retrospectively. The surgical pathology identified invasion of thymoma in 35 patients: in the lung (n = 18), pericardium (n = 11), or both (n = 6). Contact lengths between the tumor contour and lung (CLTL) or pericardium (CLTP) were measured at the maximum section of the tumor on axial CT. Univariate and multivariate analyses were performed to analyze the relationship between pathological invasion of the lung or pericardium and the clinicopathologic features. The mean CLTL and CLTP were significantly longer in patients with invasion of the neighboring organs than in those without invasion. A lobulated tumor contour was identified in 95.6% of the patients with invasion of the neighboring organs. A multivariate analysis revealed that a lobulated tumor contour was significantly associated with both lung and pericardial invasion. A lobulated tumor contour was significantly associated with lung and/or pericardial invasion in thymoma patients.

Racial and ethnic differences in thymic epithelial tumors: A single-institution retrospective analysis.

e20649 Background: Thymic epithelial tumors (TETs) are a rare, heterogeneous group of malignancies that arise from the thymus. While the etiology of TETs remains unknown, variation in incidence rates amongst racial/ethnic groups has raised the possibility of germline predispositions. Unfortunately, due to the rarity of this disease, there is a limited understanding of the impact of race/ethnicity on tumor characteristics and treatment outcomes for TET patients. We sought to characterize patient/tumor data and investigate treatment outcomes based on race and ethnicity. Methods: We conducted a single-institution, retrospective database analysis of TET patients evaluated at the IUSCCC from 1979 – 2021 from which clinical annotations were available for 477 thymoma and 164 thymic carcinoma (TC) patients. We identified 112 thymoma and 35 TC patients who were deemed to have sufficient data for evaluation of racial/ethnic characteristics. Demographic/clinical variables and therapeutic interventions, including treatment outcomes, were analyzed. Data was compiled and analyzed using descriptive statistics and the Kaplan Meier method for survival analysis via GraphPad Prism software. Results: Of the 112 thymoma patients, 29 thymoma patients presented with de novo metastatic disease at the time of diagnosis. The median age at the time of diagnosis of all patients revealed a statistically significant difference between White and Black TET patients (53.0 v. 42.0 years, *p = 0.0195). There was a trend towards significance when median age of diagnosis between White and Asian TET patients was compared (53.0 v. 48.0 years, p = 0.0633, NS). Advanced histologic subtypes, include B3 and TC, appeared predominantly in Asian and Black patients at 77.7% and 56.3%, respectively, compared to White patients (44.9%), though the finding was not statistically significant. No statistically significant differences between racial/ethnic groups regarding progression free survival for unresectable or metastatic disease were observed, regardless of histology. There was a non-significant difference in recurrence free survival for resectable thymoma in White (30.0 months) and Asian/Pacific Islander (47.0 months) patients compared to Black patients (24.0 months). Conclusions: Overall, this analysis suggests differences in the median age of diagnosis for patients with thymic malignancies based on race, raising the possibility of inherent biologic differences driving oncogenesis and symptoms at the time of presentation. While no statistically significant differences in treatment outcomes were found based on race and ethnicity, Black patients appeared to experience shorter times to recurrence after definitive surgery. Further studies to understand the mechanistic differences driving tumorigenesis and potential disparities in treatment outcomes are greatly needed in this rare tumor type.

Risk factor analysis of thymoma resection and its value in guiding clinical treatment.

In this study, relationships between clinicopathologic characteristics and progression-free survival (PFS) of patients after thymomectomy were analyzed to provide valuable suggestions regarding the treatment of thymoma. Data from 187 thymoma patients undergoing surgery at Beijing Tongren Hospital between January 1, 2006, and December 31, 2015, were retrospectively reviewed. We explored the risk factors for PFS among sex, age, thymoma-associated MG, completeness of resection, histologic type and TNM stage, and investigated their interrelationship. Among the 187 patients, 18 patients (9.63%) had tumor recurrence/metastasis, and all of whom had in situ recurrence or pleural metastasis, and most of them (10 of 18 patients) had MG symptoms that reappeared or were aggravated. Fifteen patients (8.02%) died, and myasthenic crisis was a leading cause. Based on Cox regression analysis, only age (HR = 3.16; 95% CI: 1.44-6.91; p = 0.004) and the completeness of resection (HR = 9.03; 95% CI: 2.58-31.55; p = 0.001) were independent risk factors for PFS. Furthermore, we found that the completeness of resection was related to the histologic type (p = 0.009) and TNM stage (p < 0.001) by Fisher's exact test. The results of this cohort study remind us that we should pay attention to the reappearance or aggravation of MG after thymoma resection, because it is the leading cause of death and may indicate tumor progression. Furthermore, completeness of resection was related to the histologic type and TNM stage, but it was the independent risk factors of thymoma. Therefore, R0 resection is critical to the prognosis of thymoma.