Hyperthermic intraoperative chemotherapy (HIOC) for Stage IVa thymic malignancy may improve 5-year disease-free survival

BACKGROUND AND OBJECTIVES

Stage IVa thymic malignancy has limited treatments. This study evaluated whether hyperthermic intraoperative chemotherapy (HIOC) after radical resection of Stage IVa thymic malignancy improves survival.

METHODS

All patients who underwent resection, with or without HIOC, for Stage IVa thymic malignancy at a single center from 1990 to 2021 were reviewed.

RESULTS

Thirty-four patients were identified; 22 surgery-only versus 12 surgery and HIOC (60 min cisplatin regimen 175 mg/m² ). Demographics and comorbidities were similar between groups. Three patients in each group were carcinomas; remainder were thymomas. Thirty-two patients underwent attempted macroscopic complete resection; 22 operations succeeded, 68.8%. Significant complications were similar between groups, 18.2% surgery-only versus 25.0% HIOC, p = 0.68. Median time to recurrence trended longer for HIOC patients (42.9 vs. 32.9 months in surgery-only, p = 0.77). Overall survival, 5-year, was similar (75.8% HIOC vs. 76.2% surgery-only, p = 0.91). On stratified analysis, thymoma patients with macroscopic complete resection and HIOC experienced similar 5-year Overall (80.0% vs. 100.0% surgery-only, p = 0.157) but longer trending 5-year disease-free (85.7% vs. 40.0%, p = 0.18) and 5-year locoregional recurrence-free survival (85.7% vs. 68.6%, p = 0.75).

CONCLUSIONS

This retrospective cohort study treating Stage IVa thymic malignancy with radical pleurectomy, with or without HIOC, found addition of HIOC-signaled delayed recurrence and improved disease-free survival.

Povidone-Iodine-Induced Acute Kidney Injury in a 23-Year-Old Woman: The First Clinical Case Report From the Republic of Cyprus

Povidone-iodine (PI) is considered a generally safe broad-spectrum, antiseptic substance, which is widely used in healthcare services, mostly for burn patients, in wound treatment, surgical wound irrigation, as well as for a few gynecological indications. Although it is safe, its use on mucosa can cause toxicity due to iodine absorption and the high concentration in the serum. PI toxicity is absorption depended and has been associated with severe adverse events including acute kidney injury (AKI). To our knowledge, there are only three cases of PI-induced AKI after uterine instillation in the published literature. We report a case of severe PI-induced AKI that occurred in a 23-year-old female due to iodine systemic absorption immediately post uterine instillation, in terms of infertility evaluation.

The patient was admitted to the intensive care unit (ICU), supported with mechanical ventilation and treated with renal replacement therapy (RRT). Renal function and urine output improved and the patient was discharged from ICU.

Severe adverse events may be linked to internal use, therefore, PI on mucosa should be used with extreme caution. Clinicians should be aware of iodine intoxication and possible AKI.

Importance of resection for locoregional disease control in Masaoka stage IVA thymic neoplasms

BACKGROUND AND OBJECTIVES

It is unclear if a specific strategy for simultaneous treatment of primary thymic neoplasms and pleural metastases confers benefit for Masaoka stage IVA disease. We reviewed our experience with thymic neoplasms with concurrent pleural metastases to identify factors influencing outcomes.

METHODS

Records of patients who presented with stage IVA thymic neoplasms from 2000 to 2018 were assessed. Multivariate Cox proportional hazards analyses were completed to determine predictors of progression-free and overall survival.

RESULTS

Forty-eight patients were identified, including 34 (71%) who underwent surgery. Median overall and progression-free survival were 123 and 21 months, respectively. The extent of resection varied, and was most commonly thymectomy plus partial pleurectomy (22, 65%). Median progression-free survival for patients who underwent surgical resection versus those who had not was 24 versus 12 months (P = .018). Following surgical resection, mediastinal recurrence was uncommon (2, 6%, vs 7, 50% nonoperatively). Five-year survival rates in these groups were suggestive of possible benefit to surgery (87% vs 68%).

CONCLUSIONS

Thymic neoplasms with pleural dissemination represents a treatment challenge. As part of a multidisciplinary approach, surgery appears to be associated with more favorable long-term results, although selection bias may account for some of the survival differences observed.

Povidone-iodine results in rapid killing of thymic epithelial tumour cells through cellular fixation†

OBJECTIVES

Hyperthermic pleural lavage with povidone-iodine (PVP-I) is utilized to control micrometastatic disease following cytoreductive surgery for thymic epithelial tumours (TETs). Our objective was to investigate whether PVP-I demonstrates direct cytotoxicity against human TET cells.

METHODS

Human Met-5A (immortalized mesothelial cell), IU-TAB-1 (thymoma) and Ty-82 (thymic carcinoma) cell lines were treated with serial dilutions of PVP-I (0.01-10%) for 5, 30 and 60 min at 37°C and 42°C. MTT assays and flow cytometry were used to evaluate cell death and apoptosis. Membrane permeability was assayed by intracellular staining of cleaved poly-ADP-ribose polymerase. Cellular fixation was evaluated by membrane disruption of dead cells by dimethylsulphoxide and by comparing cleaved poly-ADP-ribose polymerase staining following PVP-I with known fixatives.

RESULTS

MTT assays demonstrated that PVP-I concentrations greater than 0.5% led to rapid cell death in both TET cell lines regardless of temperature. IC50 values following 5 min of exposure to PVP-I were 8.4 mM (0.3%) and 13.3 mM (0.48%) for IU-TAB-1 and Ty-82, respectively and 8.9 mM (0.32%) for MeT-5A. Flow cytometry demonstrated that 5-min exposure of either cell line to 1% PVP-I resulted in profound cell death: 74% and 58% at 5 min and 97% and 95% at 30 min, for IU-TAB-1 and Ty-82 cells, respectively. Resistance of PVP-I-treated cells to dimethylsulphoxide lysis and similar cleaved poly-ADP-ribose polymerase expression following PVP-I and known fixatives revealed cellular fixation as the mechanism of death following PVP-I exposure.

CONCLUSIONS

PVP-I results in rapid death of human TET cells and normal mesothelial cells through a cellular fixation mechanism and may, therefore, favourably impact the control of micrometastatic disease following resection of TETs with pleural dissemination.

Hyperthermic Intrathoracic Chemotherapy (HITHOC) for Pleural Malignancies-Experience from Indian Centers

Hyperthermic intrathoracic chemotherapy (HITHOC) has been used in addition to radical surgery for primary and secondary pleural malignancies to improve local control, prolong survival, and improve the quality of life. This study was performed to study the indications, methodology, perioperative outcomes, and survival in patients undergoing HITHOC at Indian centers. A retrospective analysis of prospectively collected demographic and clinical data, perioperative and survival data of patients undergoing surgery with or without HITHOC was performed. From January 2011 to May 2018, seven patients underwent pleurectomy/decortication (P/D) or extrapleural pneumonectomy (EPP) with HITHOC and four had P/D or EPP alone at three Indian centers. P/D was performed in two and EPP in nine patients. The primary tumor was pleural mesothelioma in eight, metastases from thymoma in one, germ cell tumor in one, and solitary fibrous tumor of the pleura in one. HITHOC was performed using cisplatin. Grade 3-4 complications were seen in one patient in the HITHOC group and none in the non-HITHOC group, and one patient in the non-HITHOC group died of complications. At a median follow-up of 9 months, five patients of the HITHOC group were alive, four without recurrence, and one with recurrence. One patient in the non-HITHOC group was alive and disease-free at 24 months, and two died of progression at 18 and 36 months. HITHOC can be performed without increasing the morbidity of P/D or EPP. Most of these patients require multimodality treatment and are best managed by multidisciplinary teams.

Management of Malignant Lung Entrapment, the Oncothorax

Pleural metastasis is a common occurrence in up to 30% of patients with metastatic cancer. When lung entrapment and loculation of fluid occur, treatment is more difficult and we have named this condition "oncothorax." The malignant adhesions that entrap the lung in an oncothorax are not typically amenable to surgical decortication. The standard approach for managing these patients is to place an indwelling catheter. Other options may include pleurectomy and decortication, intrapleural hyperthermic chemoperfusion, and intrapleural photodynamic therapy. However, these procedures should be provided selectively depending on patient performance status, extent of metastatic disease, and level of experience.

Induction Therapy for Thymoma

Thymomas are uncommon tumors that can present as locally advanced tumors in approximately 30% of the patients. Stage and complete resection are the strongest prognostic factors. For locally advanced tumors, induction treatment may improve the ability to achieve a complete resection. Combination treatment with cisplatin, doxorubicin, and cyclophosphamide is the most commonly used induction regimen. Similar rates of resectability are noted with the use of induction chemotherapy and chemoradiation therapy; however, more tumor necrosis is noted with the addition of radiation.

Video assisted thoracic surgery (VATS) for recurrent thymoma

Between 10-30% of patients that undergo a radical operation for thymoma develop a recurrence in a variable range of time. The surgical treatment of thymoma relapses is an established and effective therapeutic approach, particularly for a single intrathoracic recurrence; however, no agreement has been reached on the best surgical approach and the extent of surgical resection, particularly in the most common event of pleural relapses. In the era of minimally invasive approach for most thoracic pathologies, the role of the video assisted thoracic surgery (VATS) approach for thymoma recurrence resection is still unclear and controversial: to date, only few authors have reported in their series a thoracoscopic resection of pleuro-pulmonary relapses, mostly when a single lesion was present. Furthermore, a thoracoscopic approach for mediastinal recurrence has been rarely reported after a previous sternotomy to resect the primary tumor. It is likely that in the future, the role of VATS for thymic recurrence resection will be better defined and extensively studied.

Management of metastatic malignant thymoma with advanced radiation and chemotherapy techniques: report of a rare case

Malignant thymomas are rare epithelial neoplasms of the anterior superior mediastinum that are typically invasive in nature and have a higher risk of relapse that may ultimately lead to death. Here we report a case of an advanced malignant thymoma that was successfully treated with neoadjuvant chemotherapy followed by surgical resection and subsequently with advanced and novel radiation therapy techniques. A 65-year-old male was diagnosed with a stage IV malignant thymoma with multiple metastatic lesions involving the left peripheral lung and pericardium. Initial neoadjuvant chemotherapy with a cisplatin-based regimen resulted in a partial response allowing the inoperable tumor to become operable. Following surgical resection of the residual disease, the tumor recurred within a year. The patient then underwent a course of targeted three-dimensional intensity modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT). Five years after radiation therapy, the localized soft tissue thickening at the left upper lung anterior pleural space had resolved. Seven years after radiation therapy the tumor mass had completely resolved. No recurrences were seen and the patient is well even 8 years after IMRT/IGRT with a favorable outcome. Chemotherapy with targeted three-dimensional IMRT/IGRT should be considered the primary modality for the management of advanced malignant thymoma patients.

Surgical Approaches for Stage IVA Thymic Epithelial Tumors

Thymic epithelial tumors (TET) are rare mediastinal neoplasms that can metastasize to the pleural space (stage IVA). Complete surgical resection remains the backbone of therapy for patients with early stage TET, however, the role of surgery in the management of patients with stage IVA disease is not fully defined. Published reports in this regard are mainly small, retrospective, and uncontrolled, with unclear inclusion criteria. Surgical options to manage pleural disease include metastasectomy, extrapleural pneumonectomy, and metastasectomy/pleurectomy combined with heated intrapleural chemotherapy. The choice of the most appropriate surgical strategy needs to be individualized according to the quantity and location of disease, the patient’s overall condition, as well as operator and institutional expertise. In the majority of cases, metastasectomy of pleural implants will be sufficient to achieve a complete resection. The available literature suggests that in selected patients with stage IVA TET, delivery of neoadjuvant chemotherapy followed by complete resection is a viable treatment option that can be associated with long-term survival.

Antineoplastic activity of povidone-iodine on different mesothelioma cell lines: results of in vitro study

OBJECTIVE

Povidone-iodine (PVP-I) or Betadine, owing to its antineoplastic activity, is also used as an adjuvant during intra-abdominal or intrathoracic surgery. However, the protocol of PVP-I administration has not been optimized to achieve the best antitumoural efficacy. We aimed to determine the optimal concentration of PVP-I, the time of incubation and the mechanism of cell death by analysing the effect of different doses and time of administration of PVP-I on the cell viability of different mesothelioma cell lines.

METHODS

Four different cell lines (MET 5A/normal mesothelium; H2052/sarcomatoid mesothelioma; ISTMES2/epithelial mesothelioma; MSTO/biphasic mesothelioma) were incubated with increasing concentrations of diluted PVP-I (0.0001; 0.001; 0.01; 0.1; 1%) for 5, 10, 30, 60 min and 24 h, respectively. Cell viability was determined using cell direct cytotoxicity assay and cell death was determined through flow cytometry assay analysis. The superoxide dismutase activity was assessed functionally through a specific inhibitor to evaluate the mechanism of cell death.

RESULTS

The antiproliferative effect of PVP-I varied largely among different cell lines in a dose- and time-dependent manner. At 0.1% concentration for 10 min of incubation, the percentage of viable cells was 0.5 ± 0.1; 0.8 ± 0.5 and 0% (P < 0.01) for MET5A, ISTMES2 and MSTO, respectively. Conversely, the same concentration did not significantly affect the H2052 cell line which was completely suppressed at a 1% concentration of PVP-I. Double staining of Annexin V and DNA showed that PVP-I induced cell death in all four cell lines via necrosis depending on PVP-I concentration. However, H2052 was found to be more resistant than MSTO, ISTMES2 and MET 5A cells lines. The activity of superoxide dismutase was significantly inhibited in all cell lines.

CONCLUSIONS

Our results confirmed the anti-neoplastic activity of PVP-I especially on ISTMES2 and MSTO cell lines. With respect to chemotherapy pleural irrigation, washing with PVP-I is cost-effective and easy. If confirmed by larger studies, our findings suggest that the intrapleural irrigation with PVP-I (0.1% concentration for 10 min) in patients with epithelial or biphasic mesothelioma undergoing cytoreductive surgery might be applied in thoracic surgery practice to prevent neoplastic cell growth.