P14.88 Management of primary CNS lymphomas. Experience of 32 cases

BACKGROUND Lymphomas (primary and secondary) are rare tumors of the central nervous system. They can involve both the supratentorial areas and the posterior cranial fossa. Modern management of patients with suspected CNS lymphoma should include a stereotactic or navigation-guided biopsy and subsequently carrying out chemotherapy and, in rare cases, radiosurgery. MATERIAL AND METHODS We analyzed our experience of the diagnosis and treatment of PCNSL. Our work included 32 patients with PCNSL. The study did not include patients with suspected CNS lymphoma, according to MRI data, in whom the diagnosis was not confirmed after biopsy. RESULTS Thirty patients underwent biopsy (20 - navigation guided, 1 - open, 9 - “burr hole”) with preliminary intraoperative histological verification. Gross total resection was performed in 2 cases since, according to preoperative MRI data, it was assumed that the patient had glial tumors. Postoperative histological examination confirmed the diagnosis of CNS lymphoma in all cases. Subsequently, after detailed histological and immunohistochemical studies, 30 patients underwent intra-arterial chemotherapy or high-dose chemotherapy according to NCCN protocols. Palliative treatment was recommended in 2 cases due to acute deterioration of patients. In our work, we would like to present a diagnostic algorithm and treatment regimens used in the management of our patients. CONCLUSION In the treatment of CNS lymphomas, careful histological verification is required, which is possible if several key points are performed - discontinuation of dexamethasone at least 24 hours before the biopsy, MRI for intraoperative neuronavigation after discontinuation of dexamethasone, intraoperative preliminary histological verification. In our opinion, complete removal of the tumor is possible if there are no risks of developing a persistent neurological deficit. Various methods of opening the blood-brain barrier are currently used, which can significantly reduce the effective dosage of drugs and, accordingly, the side effects. Further research is needed to determine the dependence of the prognosis of the disease on the type of surgery (biopsy or resection).

Giant breast fibroadenoma in pregnancy

Overview Objective: To present unusual case of rapidly growing breast fibroadenoma during pregnancy. Case report: Breast fibroadenomas are hormone-dependent tumors which can grow rapidly during pregnancy. We present a case of giant fibroadenoma, first detected before pregnancy, which grew rapidly under the influence of pregnancy hormones and was excised in the third trimester. Conclusion: Fibroadenomas are benign breast lesions in young women. They are hormone-dependent tumors, which can grow rapidly especially during pregnancy and/ or lactation and imitate malignancy. In each case of a newly created breast lesion, it is necessary to proceed responsibly to the clinical examination, which is a base for further decision concerning the necessity of taking a bio­psy for histological verification. Keywords: breast fibroadenoma – pregnancy – lactation – phyllodes tumor

Scar endometriosis diagnosed as incisional hernia before surgery

Scar endometriosis is a rare condition highly related to history of abdominal surgery. Due to the low incidence, it is often misdiagnosed. A woman presented to the surgery outpatient clinic with a mass near her C-section scar. Physical examination and ultrasound suggested Incisional Hernia while intraoperative finding revealed a mass suggestive of endometriosis which later confirmed by pathology examination. Scar endometriosis is a common subtype of extra-pelvic endometriosis. Iatrogenic transplantation is speculated to be its etiopathogenesis. Preoperatively, it is challenging to differentiate endometriosis from another abdominal masses. The definitive diagnosis is based on laparoscopy or surgery with histological verification. Chronic pain is complex and often involves multiple factors beyond simply a diagnosis of endometriosis, but it is important to think of endometriosis on women patients presenting with a mass and cyclic pain with history of surgery involving a large amount of endometrial cell.

Histological verification of the treatment effect of tirabrutinib for relapsed/refractory primary central nervous system lymphoma

Tirabrutinib (ONO/GS-4059; Ono Pharmaceutical) is a newly developed drug that selectively and irreversibly inhibits Bruton’s tyrosine kinase (BTK) and has been approved in Japan for treating relapsed/refractory primary central nervous system lymphoma (PCNSL). However, its therapeutic effect is yet to be verified at the pathological level in human patients. A 64-year-old patient with recurrent PCNSL enrolled in the phase I/II clinical trial of tirabrutinib, a second-generation BTK inhibitor designed for treating relapsed/refractory PCNSL. The left cerebellum lesions on magnetic resonance imaging disappeared one month after tirabrutinib treatment. The patient died because of suspected pneumocystis pneumonia and acute exacerbation of interstitial pneumonia 43 days after starting tirabrutinib. An autopsy confirmed no viable tumor cells in the entire brain, including the left cerebellum lesion, confirming complete obliteration of tumor cells by tirabrutinib. This letter pathologically confirms the effect of tirabrutinib on relapsed/refractory PCNSL for the first time in humans.Trial registration: JapicCTI-173646. Registered 14 July 2017, https://www.clinicaltrials.jp/cti-user/trial/ShowDirect.jsp?japicId=JapicCTI-173646.

IMPROVED DIAGNOSISFOR ORAL MUCOSAL TUMORSIN THE DENTIST’S OFFICE

Based on currently available literature, clinical examination remains the major method when handling cases of suspected malignancy. However, this method does not allow diagnosing cancer, due to which a large group of patients with possible oral mucosa cancer are referred to an oncologist. The search and use of affordable non-invasive methods for early diagnosis of oral mucosa tumors is an urgent issue facing the health system. The study involved analyzing 134 records of outpatients examined at the Samara Regional Oncological Clinic who were referred by dentists within 2014-2019 from the local polyclinic in Samara due to detection of tumors in oral mucosa and who underwent a biopsy. The patients were divided into two groups according to the examination methods. The inclusion criteria were: detection of various superficial oral mucosa neoplasms; referral from the dentist. The exclusion criteria were as follows: patients with submucosal oral cavity neoplasms referred to the oncologist by other medical specialists or self-referred patients. The control group included 63 patients who, after a conventional examination (including interview, examination, palpation), underwent an incisional biopsy followed by morphological examination at the oncologist’s office. In the major group, in 71 patients at their respective initial dental appointments a special examination algorithm was applied. This algorithm entailed an assessment of the identified risk factors. Indications for biopsy were identified using the histological verification index (HVI). Apart from the conventional examination methods (interview, examination, palpation), autofluorescence stomatoscopy was used, this being done for the purpose of differential diagnostics of inflammation, precancerous and malignant issues, depending on the glow type. In the main group, the initial stages of oral mucosa cancer were detected in 17 patients after biopsy; in the control group – in 4 patients (p=0.004). The developed algorithm used for scoring the patient’s clinical examination data combined with autofluorescence stomatoscopy allowed diagnosing accurately (90% of reliability) precancerous and cancerous diseases, as well as to use invasive research methods (biopsy) strictly following the indications. Aim of study: to improve diagnosis of oral mucosa neoplasms through improvement of the examination algorithm.

Recurrent catamenial tension pneumothorax in a patient with endometriosis

Catamenial pneumothorax is a rare cause of spontaneous pneumothorax in women of reproductive age and one of the thoracic endometriosis manifestations. Researchers have shown an increased interest in catamenial pneumothorax but a clear treatment strategy for this pathology has not been developed yet. The thoracoscopic revision of the pleural cavity, as well as the identification and subsequent histological verification of ectopic endometriosis foci, play a crucial role in patient management. This case report describes the successful treat-ment of a patient with recurrent catamenial tension pneumothorax and following multidisciplinary analysis. Keywords: catamenial pneumothorax, thoracic endometriosis, histological examination

Ganglioneuroma as the phenomenon of neuroblastoma maturation

Ganglioneuroma (GN) represents a mature, well-differentiated tumor arising from the sympathetic nervous system. Mostly developing de novo, GN can appear during the treatment course of poorly differentiated or undifferentiated tumors of the sympathetic nervous system, such as neuroblastoma, or as a result of their spontaneous maturation. In this article we report three clinical cases of spontaneous and induced maturation of neuroblastoma (primary tumor and metastatic lesion) to GN. Histological verification of long-lasting stable or progressing residual tumor mases in patients with neuroblastoma stratified to the observation group plays a pivotal role as it may significantly affect the treatment course. The patients' parents gave their consent to the use of their child's data, including photographs, for research purposes and in publications.

Inhibitory interneurons show early dysfunction in a SOD1 mouse model of ALS

Few studies in amyotrophic lateral sclerosis (ALS) focus on the premotor interneurons synapsing onto motoneurons (MNs). We hypothesized inhibitory interneurons contribute to dysfunction, particularly if altered before MN neuropathology. We directly assessed excitability and morphology of ventral lumbar glycinergic interneurons from SOD1G93AGlyT2eGFP (SOD1) and wildtype GlyT2eGFP (WT) mice. SOD1 interneurons were smaller but density was unchanged. Patch clamp revealed dampened excitability in SOD1 interneurons, including depolarized PICs and voltage threshold. Renshaw cells (RCs; confirmed with immunohistochemistry) showed similar dampened excitability. Morphology and electrophysiology were used to create a “random forest” statistical model to predict RCs when histological verification was not possible. Predicted SOD1 RCs were less excitable (consistent with experimental results); predicted SOD1 non-RCs were more excitable. In summary, inhibitory interneurons show very early perturbations poised to impact MNs, modify motor output, and provide early biomarkers of ALS. Therapeutics like riluzole that universally reduce CNS excitability could exacerbate this dysfunction.

Identification of the site for biopsy in oral mucosa cancer diagnostics

Objective to refine the method of incisional biopsy in the diagnosis of oral mucosa cancer using the auto-fluorescent stomatoscopy. Materials and method.The study was conducted on the base of the Samara Regional Clinical Oncology Center. The inclusion criterion for patients was the diagnose of the oral mucosa cancer of various localization. Patients were divided into 2 groups. The main group included patients (n=43), who were being diagnosed for cancer with the help of optimized incisional biopsy of the oral mucosa formations, using the "AFS-400" autofluorescence complex and glasses with a green light filter for identification. The patients of the control group (n=46) received the standard biopsy procedure under direct vision. Results.The first incisional biopsies revealed cancer in 25 (54%) patients of the control group and in 36 (84%) patients of the main group. A histological verification of the diagnosis was necessary in 7 (16%) patients of the main group and required the second biopsy. In the control group, for the same purpose, 17 (37%) patients underwent the second biopsy and 4 (9%) patients required the third biopsy procedure. Exophytic-papillary forms of cancer were the most complex for histological verification. The primary biopsy of these cases was effective in 16 (37%) patients in the main group and in 8 (17%) patients in the control group (p = 0.036). In patients with initial stages of cancer (I-II), with the first incision biopsy, the histological verification of cancer was achieved in 16 (37%) cases in the main group and in 8 (17%) cases in the control group (p = 0.036). Conclusion.The use of the "AFS-400" autofluorescent complex and glasses with a green light filter for incisional biopsy of oral mucosal formations allows histological verification of cancer with the first biopsy in 84% of cases, including in stages I - II in 16 (37%) cases and in exophytic papillary forms in 16 (37%) cases. The significant difference was registered for the similar indicators of the control group (p = 0.036).