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

PURPOSE: 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. METHODS: 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. RESULTS: 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 6 months 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%. CONCLUSION: The WHO type of thymoma is an informative predictor of postoperative MG status in patients with MG-related thymoma.

Prognostic factors affecting survival in patients with non-small cell lung cancer treated with salvage surgery after drug therapy: a multi-institutional retrospective study.

BACKGROUND: The prevalence of salvage surgeries after drug therapy for non-small cell lung cancer (NSCLC) has risen, mainly due to recent progress in molecular-targeted drugs and immune checkpoint inhibitors for NSCLC. While the safety and effectiveness of salvage surgery after drug therapy for NSCLC have been studied, its indications remain unclear. We aimed to identify the prognostic factors affecting survival in patients with advanced-stage (stages III-IV) NSCLC treated with salvage surgery after drug therapy. METHODS: A retrospective investigation was conducted on patients who received salvage surgery after drug therapy at four hospitals between 2007 and 2020. Salvage surgery was defined as surgery after drug therapy for local progression, tumor conversion to resectable status, and discontinuation of prior drug therapy owing to serious complications. RESULTS: Thirty-two patients received cytotoxic agents alone (n = 12 [38%]), tyrosine kinase inhibitors (TKIs; n = 16 [50%]), or immune checkpoint inhibitors (n = 4 [13%]) as prior drug therapy. In 11 (34%) and 21 (66%) patients, the clinical stage before treatment was III or IV, respectively. The median initial and preoperative serum carcinoembryonic antigen (CEA) levels were 10.2 (range, 0.5-1024) ng/mL and 4.2 (range, 0.6-92.5) ng/mL, respectively. Among the patients, 28 (88%) underwent lobectomy, 2 (6%) underwent segmentectomy, and 2 (6%) underwent wedge resection. Complete resection of the primary lesion was accomplished in 28 (88%) patients. Postoperative complications were documented in six (19%) patients. Mortality rates were 0% at 30 days and 3% at 90 days post-operation. The 5-year overall survival rate stood at 66%, while the 5-year progression-free survival rate was 21%. Multivariate analyses showed that prior TKI therapy and preoperative serum CEA level < 5 ng/mL were prognostic factors influencing overall survival (hazard ratio [95% confidence interval]: 0.06 [0.006-0.68] and 0.03 [0.002-0.41], respectively). The 5-year overall survival in the 11 patients with both favorable prognosticators was 100%. CONCLUSIONS: In this study, prior TKI therapy and preoperative serum CEA level < 5 ng/mL were favorable prognostic factors for overall survival in patients with NSCLC treated with salvage surgery. Patients with these prognostic factors are considered good candidates for salvage surgery after drug therapy.

[Clinicopathological Features and Imaging Characteristics of Pulmonary Mucosa-associated Lymphoid Tissue Lymphoma].

BACKGROUND: Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease. We report seven cases of pulmonary MALT lymphoma. CASES: Chest computed tomography (CT) revealed various morphological features, including a solitary mass, a solid nodule, and ground-glass opacity. Multiple nodules were observed in one patient. However, the tumor margins were ill-defined in all seven cases, and air bronchograms were identified in five cases. The solitary mass was found to extend along the pulmonary lymphatic vessels. Six patients underwent R0 resection, while one underwent an open lung biopsy. Histopathological findings in all seven cases showed lymphoepithelial lesions. Regarding their immunohistological findings, all patients were diagnosed with pulmonary MALT lymphoma. Two patients received postoperative chemotherapy with rituximab. The progression-free survival time was 52 (range, 22-122) months. Postoperative course was uneventful in all patients. CONCLUSION: MALT lymphoma is characterized by an ill-defined margin, air bronchogram, and tumor extension along the pulmonary lymphatic vessels, all of which aid in diagnosis. MALT lymphoma is a low-grade lymphoma, and the prognosis is favorable. Therefore, follow-up examination without treatment can be one of the therapeutic options if patients are diagnosed with pulmonary MALT lymphoma.

Clinicopathological and prognostic features of operable non-small cell lung cancer patients with diabetes mellitus.

BACKGROUND: The aim of this study was to investigate the clinicopathological and prognostic features of operable non-small cell lung cancer (NSCLC) patients with diabetes mellitus (DM). METHODS: A total of 1231 surgically resected NSCLC patients were retrospectively reviewed. Clinicopathological characteristics were compared between patients with DM (DM group, n = 139) and those without DM (non-DM group, n = 1092). The clinical factors associated with postoperative complications and prognostic factors were identified. RESULTS: The DM group had distinct clinicopathological features. No significant differences in histological invasiveness or stage were found. The presence and control status of DM were independent predictors of postoperative complications. No significant differences in recurrence-free survival or cancer-specific survival were observed; however, the DM group had worse overall survival (OS). The DM group had a higher number of deaths from other diseases than the non-DM group, and these patients had significantly higher postoperative hemoglobin A1c levels than patients with cancer-related death. CONCLUSION: The presence and control status of preoperative DM are useful predictors of both postoperative complications and OS in operable NSCLC patients. Concomitant diabetes-related complications have a negative effect on long-term survival in diabetic NSCLC patients, and long-term glycemic control is important to prolong OS.

Debulking surgery for malignant tumors: the current status, evidence and future perspectives.

Debulking surgery, also called cytoreductive surgery, is a resection of the tumor as much as possible and an intended incomplete resection for unresectable malignant tumors. Since the most important principle in surgical oncology is complete R0 resection, debulking surgery goes against the basic principle and obscures the concept of operability. However, debulking surgery has been advocated for various types of advanced malignant tumors, including gynecological cancers, urological cancers, gastrointestinal cancers, breast cancers and other malignancies, with or without adjuvant therapy. Positive data from randomized trials have been shown in subsets of ovarian cancer, renal cell carcinoma, colorectal cancer and breast cancer. However, recent trials for renal cell carcinoma, colorectal cancer and breast cancer have tended to show controversial results, mainly according to the survival improvement of nonsurgical systemic therapy alone. On the other hand, debulking surgery still has a therapeutic role for slow-growing and borderline malignant tumors, such as pseudomyxoma peritonei and thymomas. The recent understanding of tumor heterogeneity and clonal evolution responsible for malignancy and drug resistance indicates that select patients may obtain prolonged survival by the synergistic effect of debulking surgery and novel systemic therapy. This review aimed to describe the current status and evidence of debulking surgery in a cross-organ manner and to discuss future perspectives in the current era with advances in systemic therapy.

Four cases of completion lobectomy for locally relapsed lung cancer after segmentectomy.

BACKGROUND: Although completion lobectomy is the treatment of choice for local recurrence of non-small cell lung cancer after segmentectomy, few cases have been reported. We report four patients who underwent completion lobectomies for staple line recurrence after segmentectomy for stage I non-small cell lung cancer. CASE PRESENTATION: Three women aged 65, 82, and 81 years underwent completion lower lobectomy after superior segmentectomy of the same lobe for local recurrence of stage I non-small cell lung cancer. A 67-year-old man, who had a tumor recurrence on the staple line after apical segmentectomy with superior mediastinal nodal dissection for stage I non-small cell lung cancer, underwent completion right upper lobectomy. These four patients underwent segmentectomy because of comorbidities or advanced age. Local recurrence was confirmed by computed tomography-guided needle biopsy. The interval between the two operations was 37, 39, 41, and 16 months, respectively. Although minimal hilar adhesion was seen for the three completion lower lobectomies, tight adhesions after apical segmentectomy made completion right upper lobectomy quite difficult to dissect, which led to injury of the superior pulmonary vein. No recurrence was recorded after completion lobectomies for 62, 70, 67, and 72 months, respectively. CONCLUSIONS: Although completion lobectomy is one of the most difficult modes of resection, among several completion lobectomies, completion lower lobectomy after superior segmentectomy without superior mediastinal nodal dissection was relatively easy to perform because of fewer hilar adhesions.

[Role of Surgery in Multimodality Treatment for Non-small Cell Lung Cancer;Current Status and Future Perspectives].

Recent improvement of outcomes for resected non-small cell lung cancer (NSCLC) has been contributed not only by increased detection of early-stage disease and improvement of preoperative diagnosis/perioperative management but also by improvement of multimodality treatment. The introduction of newly developed systemic therapies including molecular targeted agents and immune checkpoint inhibitors dramatically changed clinical outcomes of advanced NSCLC. Accordingly, the role of surgery during the multimodality treatment will be changed more than ever. In this article, we overviewed the current status of the multimodality treatment for clinical stageⅢ (N2)disease and postoperative adjuvant therapy and discussed the role of surgery during these situations. We also discussed the future perspectives of the role of surgery during the multimodality treatment for advanced NSCLC.

Clinicopathological features of colloid adenocarcinoma of the lung: A report of six cases.

OBJECTIVES: Colloid adenocarcinoma of the lung (CA) is a rare neoplasm that is associated with abundant mucin, which destroys alveoli. We evaluated the clinicopathological features of CA. METHODS: A total of 4,648 patients underwent surgical resection of primary lung cancer at our institution from 2002 to 2014. We analyzed the clinicopathological features of CA in six (0.13%) of these patients. RESULTS: All patients were asymptomatic. The median age was 60.5 years. The median tumor size was 2.4 cm. All tumors appeared as solitary solid nodules on computed tomography (CT). Four of the six showed intense (18) F-fluorodeoxyglucose positron emission tomography ((18) F-FDG-PET) accumulation, and the remaining two showed weak (18) F-FDG accumulation. All patients underwent lobectomy with systematic lymph node dissection. Histologically, CAs presented with various degrees of a non-mucinous component in addition to abundant mucin. Only one patient with pN2 had recurrence. CONCLUSIONS: On CT, CA appears a solitary solid nodule. Further, FDG-PET findings present various (18) F-FDG accumulations. Lobectomy with systematic lymph node dissection is an appropriate procedure in view of lymph node metastasis. Since the definitive diagnosis of CA of the lung is difficult, further immunohistochemical and genetic analyses are needed. J. Surg. Oncol. 2016;114:211-215. © 2016 Wiley Periodicals, Inc.

Clinical impact of multiple pectus bars on surgical outcomes following pectus excavatum repair.

OBJECTIVES: The Nuss procedure, a minimally invasive surgery for pectus excavatum, has undergone various improvements. However, the impact of using multiple bars on thoracic shape changes and surgical outcomes remains unclear. METHODS: We retrospectively evaluated patients who underwent the Nuss procedure for pectus excavatum between August 2014 and September 2021. We divided the patients into 2 groups based on the number of bars placed and identified differences in surgical outcomes and morphological characteristics. RESULTS: A total of 225 patients were evaluated, of whom 132 were classified into the ≤2 bar group (using 1 or 2 bars) and 93 into the ≥3 bar group (using 3 or more bars). There was no difference in the preoperative Haller index [median (interquartile range), 4.59 (3.67-6.16) vs 4.67 (4.12-6.14), P = 0.227], and asymmetric excavatum was more frequently observed in the ≥3 bar group (81% vs 51%, P < 0.001). The preoperative sternal torsion angle was larger in the ≥3 bar group, but no difference was found between the 2 groups postoperatively. The incidence of postoperative complications (≥grade 3) was comparable between groups (10% vs 17%, P = 0.105); however, postoperative pleurisy was more frequently observed in the ≥3 bar group (12% vs 4%, P = 0.021). In univariable and multivariable analyses, ≥3 bar placement was the only risk factor for postoperative pleurisy. CONCLUSIONS: The placement of multiple bars (≥3 bars) is useful for the correction of asymmetric pectus excavatum, but attention should be paid to the potential risk of postoperative pleurisy.

Nuss procedure for the treatment of pectus excavatum with dyspnea following oropharyngeal cancer surgery: a case report.

Pectus excavatum (PE) causes cardiopulmonary dysfunction depending on the degree and form of the depression. The patient was a 74-year-old woman with a history of PE. Fourteen years ago, a total glossolaryngectomy was performed for oropharyngeal cancer. Two years later, the patient gradually experienced difficulty in breathing. Computed tomography (CT) revealed severe PE and right main bronchial stenosis. We performed a Nuss procedure for PE repair to surgically release the stenosis of the right main bronchus. Postoperative chest CT showed improvement in the sternal depression and right main bronchial stenosis. Furthermore, shortness of breath was relieved postoperatively. Oropharyngeal cancer surgery may cause tracheal support disruption, leading to leftward shift and severe stenosis of the right main bronchus due to sternum depression. This is an important report regarding respiratory distress caused by a combination of PE and post-oropharyngeal cancer surgery.

Quality of life, psychological states, and personality traits in patients with pectus excavatum.

Objective: The quality of life (QOL) and psychological states of patients with pectus excavatum (PE) have yet to be well understood. This study aimed to evaluate the health-related QOL (HRQOL), psychological states, and personality traits of patients with PE, alongside the associations of these factors with the severity of PE. Methods: A cross-sectional evaluation was prospectively performed in patients scheduled to undergo PE repair surgery between July 2019 and April 2021. The primary outcome was the patients' HRQOL, and the secondary outcomes were depression, social anxiety, self-efficacy, and personality traits. Results: In total, 129 patients were subjected to analyses. Patients' HRQOL had a lower role component summary score (mean ± standard deviation: 41.8 ± 12.8, P < .001) than the general population controls. Patients' HRQOL had a significantly better physical component summary (54.0 ± 10.4, P < .001) and mental component summary (53.3 ± 8.8, P < .001) than that of the general population. Fourteen patients' (10.9%) and 56 patients' (43.4%) scores indicated the presence of depression and social anxiety disorder, respectively. Patients' self-efficacy (46.1 ± 11.4, P, .001) and level of extraversion (46.5 ± 11.8, P < .001) were lower than those of the general population. No significant correlation was found between the severity of PE and these scores. Conclusions: Our study revealed that patients with PE had decreased social-role QOL, depressive tendencies, increased social anxiety, lower self-efficacy, and introversion. No correlation between the severity of PE and the patients' psychological outcomes leads us to conclude that surgical implications of PE should not be decided solely by a physical index.

Survival impact of pathologic features after salvage lung resection following definitive chemoradiotherapy or systemic therapy for initially unresectable lung cancer.

PURPOSE: Salvage surgery for primary lung cancer is expected to become increasingly common. This study aimed to clarify the survival impact of pathologic characteristics after salvage surgery. METHODS: Consecutive patients who underwent salvage surgery following definitive chemoradiotherapy or systemic therapy for initially unresectable lung cancer from 2010 to 2020 were enrolled in this study. The tumor slides were reviewed to determine the size of the tumor bed and the proportions of viable tumor, necrosis, and stroma. RESULTS: A total of 23 patients were evaluated, and 18 had clinical stage IIIB-IV disease. Six received chemoradiotherapy and 17 received systemic therapy alone. A major pathologic response (MPR, ≤ 10% of viable tumor) was observed in 6 patients, and 4 patients achieved a pathological complete response. The 3-year overall and recurrence-free survival rates (OS and RFS) were 78.6% and 59.2%, respectively. There was no significant difference in OS between patients with and without MPR, and even non-MPR patients achieved a favorable 3-year OS of 70.2%. Meanwhile, patients with high (≥ 30%) stroma showed significantly better OS than those with low (< 30%) stroma (3-year OS: 100% vs. 23.3%, p < 0.001). CONCLUSIONS: This study showed that the proportion of stroma can be useful for predicting long-term survival after salvage surgery. Further large-scale studies are warranted to confirm the current findings.

Combined Ravitch and Nuss procedure for patients with severe pectus excavatum: technique and initial results.

The Nuss procedure for pectus excavatum (PE) is both less invasive and very simple compared to the Ravitch procedure. However, it may be difficult to perform the Nuss procedure in cases of severe PE. Therefore, we developed a Combined Ravitch and Nuss (CRN) procedure and examined its effectiveness in patients with severe PE. Nine patients with severe PE underwent the CRN procedure. Data on patient characteristics and perioperative results were collected retrospectively. The median Haller index (HI) was 15.4 (range, 6.3-29.3). No significant intraoperative adverse events were noted. Postoperatively, marked improvements in HI were seen in all cases (3.29, range, 2.72-4.96). Two surgical site infections on the shallow layer and one wound seroma occurred. No recurrences were observed during the observation period. Our novel CRN procedure is useful for achieving adequate and sustainable sternal elevation with less invasiveness for patients with severe PE.

Combined Ravitch and Nuss procedure for pectus excavatum with dyspnea following scoliosis repair.

Pectus excavatum (PE) is often associated with scoliosis and can elicit cardiovascular disturbances under rare conditions. Here we report a patient who was treated with a combined Ravitch and Nuss procedure for PE with dyspnea following scoliosis repair to improve her symptoms. The patient was a 49-year-old woman with a history of PE and scoliosis. Right inferior pulmonary vein stenosis was caused by posterior spinal fusion for scoliosis prior to the PE repair. We could safely correct the chest wall deformity and treat dyspnea by performing a modified Ravitch repair in combination with the Nuss procedure.

A 70-Year-Old Woman With Long-Term Nonresolving Pneumonia.

CASE PRESENTATION: A 70-year-old woman who had received a diagnosis of pneumonia in the right lower lobe was treated with antibiotics at a general practitioner's clinic 9 months earlier. Her pneumonia had improved, but the cough and lung infiltrates persisted for > 6 months, so the patient was referred to our hospital. She had undergone surgery for breast cancer 30 years earlier but had no other medical history. She was not taking any medications and had no history of smoking, including passive smoking.

Separate evaluation of unilateral lung function using upright/supine CT in a patient with diaphragmatic paralysis.

Background: Unilateral diaphragmatic paralysis is a condition in which the unilateral diaphragm is paralyzed and elevated. Orthopnea due to lung compression by an elevated diaphragm in the supine position is common in patients with unilateral diaphragmatic paralysis. Although its symptom is posture-dependent, the effect of posture on lung function in unilateral diaphragmatic paralysis has not been studied. Computed tomography (CT) can be used to assess lung volume. However, conventional CT cannot be performed in the upright position. A pulmonary function test can be performed in both upright and supine positions. However, it cannot evaluate the function of each lung separately. Case presentation: We report a case of a 79-year-old man with unilateral diaphragmatic paralysis. He presented with difficulty in inspiration, specifically in the supine position, and underwent both conventional supine CT and newly developed upright CT to assess the effect of posture on the function of each lung. The difference between expiratory and inspiratory lung volumes on CT in the supine position was less than that in the upright position by 46% and 4% on affected and healthy sides, respectively. We previously reported that the difference between expiratory and inspiratory lung volumes on CT correlated with inspiratory capacity on the pulmonary function test. A 46% decline in inspiratory capacity on the affected side in the supine position likely caused orthopnea in this patient. Conclusions: Supine/upright CT is helpful to assess the influence of posture on unilateral lung function in patients with unilateral diaphragmatic paralysis.

Double stapling method for closure of intraoperative alveolar air leakage adjacent to the staple line: a randomized experimental study on ex vivo porcine lungs.

Background: Alveolar air leakage from a pleural defect around the staple line is one of the complications after wedge resection of the lung. An intraoperative closure of the pleural defect by suturing can cause additional pleural rupture due to tension of the pleura adjacent to staple lines. Therefore, we have introduced a novel closure method for pleural defect adjacent to the staple line, named the double stapling method. This study compared the efficacy of two closure methods; the double stapling method and conventional suturing method with pledgets using ex vivo porcine lungs. Methods: The double stapling method involves closing the pleural defect by suturing the two parallel staple lines at both sides of the pleural defect. This method was developed to distribute the pleural tension around the needle holes of suturing. As a model of pleural defect adjacent to the staple line after wedge resection, wedge resection of the caudal lobe of left porcine lungs was performed, and a superficial square pleural defect (10 mm × 10 mm) adjacent to the staple line was made by scalpel. The defect was closed using the following two methods: (I) suturing with pledgets (n=10); and (II) double stapling method (n=10). The lobe was inflated in water at an airway pressure of 20, 25, and 30 cmH2O; closure success or failure was judged by the absence or presence of air leakage. Results: The closure success was confirmed in 2 (20%) out of 10 cases in the suturing with pledgets group and 9 (90%) out of 10 in the double stapling method group (P=0.007). In 4 out of 10 cases in the suturing with pledgets group, new pleural clefts longer than 3 mm were created around the needle holes of suturing. Conclusions: Ex vivo experiments have suggested the superiority of the double stapling method for the intraoperative closure of alveolar air leakage adjacent to the staple line after wedge resection, compared to conventional suturing with the pledget method.

Feasibility and safety of percutaneous cryoablation under local anesthesia for the treatment of malignant lung tumors: a retrospective cohort study.

Background: In our institution, computed tomography (CT)-guided percutaneous cryoablation has been performed in patients with malignant lung tumors under local anesthesia. This study aimed to examine the feasibility and safety of percutaneous cryoablation for the treatment of malignant lung tumors. Methods: From July 2002 to December 2016, 227 patients (56 with primary lung cancer and 171 with metastatic lung tumor) underwent percutaneous cryoablation for the treatment of malignant lung tumors using a cryosurgical unit at our institution. Demographic factors, duration of post-treatment hospitalization, and adverse event and mortality rates were retrospectively investigated in 366 treatment sessions targeting 609 lesions. Results: The median diameter of the targeted tumor was 1.3 cm. All the cryoablation procedures were completed under local anesthesia, and the median duration of post-treatment hospitalization was two days. Adverse events (grade 2 or higher) were observed in 79 sessions (21.6%), with pneumothorax being the most common. In five sessions (1.4%), patients had grade 3 adverse events. There was no 30-day mortality; however, there were two 60-day mortality (0.5%) due to acute exacerbation of interstitial pneumonia. In multivariate analysis, independent predictors of adverse events were comorbid interstitial pneumonia [odds ratio (OR) =2.20; 95% confidence interval (CI): 1.04-4.64] and no history of pulmonary resection on the treated side (OR =3.04; 95% CI: 1.65-5.62). Conclusions: Cryoablation is a feasible and safe treatment for malignant lung tumors with acceptable adverse event rates. However, the mortality risk in patients with comorbid interstitial pneumonia should be fully recognized.

Safety and efficacy of salvage surgery for non-small cell lung cancer: a retrospective study of 46 patients from four Keio-affiliated hospitals.

OBJECTIVES: Advances in drug therapy and radiotherapy for non-small cell lung cancer resulted in an increased number of salvage surgeries for initially unresectable tumors. This study aimed to evaluate the safety and efficacy of salvage surgery for non-small cell lung cancer. METHODS: We defined salvage surgery as (1) surgery for local recurrence/residual tumor after definitive chemoradiotherapy/radiotherapy (salvage surgery in a narrow sense) or (2) conversion surgery after non-surgical treatment. We retrospectively analyzed patients who underwent salvage surgery at four Keio University-affiliated hospitals. RESULTS: Forty-six patients were included. The initial clinical stage was I in 4 patients (9%), III in 19 (41%), and IV in 23 (48%). Initial treatment before salvage surgery was chemoradiotherapy in 10 patients (24%), radiotherapy in 4 (9%), and drug therapy in 32 (67%). Pneumonectomy, lobectomy, segmentectomy, and wedge resection were performed in 2 (4%), 37 (80%), 3 (7%), and 4 (9%) patients, respectively. Complete resection was achieved in 41 patients (89%). Postoperative complications occurred in 11 patients (24%). Initial chemoradiotherapy/radiotherapy was an independent predictor of postoperative complications (odds ratio 10, p = 0.03). The 30- and 90-day mortality rates were 0 and 2%, respectively. The 5-year overall and progression-free survival rates were 66 and 30%, respectively. CONCLUSION: The safety and efficacy of salvage surgery for non-small cell lung cancer were acceptable. Salvage surgery was a viable treatment option for selected patients with recurrent/residual tumors after non-surgical treatments.