Endobronchial metastasis secondary to occulting renal cell carcinoma: literature review and a rare case report.

BACKGROUND: Endobronchial Metastasis from extrathoracic tumors is a rare neoplasm that accounts for approximately 1.1% of total endobronchial malignancies. The most common primary tumors associated with EBM are from the colorectal, breast, and kidney regions. Although it represents a late manifestation in the context of tumor progression, it can rarely antedate the diagnosis of the primary tumor. CASE PRESENTATION: A 67-years-old male was referred from another city hospital to our thoracic surgery department due to a 4-months history of hemoptysis and productive cough. A chest X-ray and computed tomography scan showed a soft-tissue mass within the left main bronchus and atelectasis of the anterior segment of the left upper lobe. Furthermore, a flexible bronchoscopy revealed a hypervascular lesion occluding completely the left upper lobe bronchus. The patient underwent lobectomy and pathological examination suggested endobronchial metastasis from clear cell renal cell carcinoma. A second computed tomography scan of the abdomen and pelvis showed a well-defined mass arising from the lateral aspect of the right kidney; therefore, the patient underwent right radical nephrectomy three weeks later and pathology confirmed the diagnosis of clear renal cell carcinoma with endobronchial metastasis. CONCLUSION: Despite its rarity, physicians should consider the possibility of endobronchial metastases in the setting of endobronchial lesions. Proper diagnostic approaches should also be considered to rule out the potential of asymptomatic extrathoracic neoplasms. In this manuscript, we aimed to report a rare case -the first from Syria to our knowledge- of an endobronchial metastasis that preceded the diagnosis of renal cell carcinoma. Importantly, we reviewed the existing literature and discussed the diagnostic and treatment approaches.

Triple-negative apocrine carcinoma as a rare cause of a breast lump in a Syrian female: a case report and review of the literature.

BACKGROUND: Apocrine carcinoma is a rare tumor that constitutes < 4% of all breast malignancies, characterized by the proliferation of large atypical cells with strictly defined borders, abundant eosinophilic cytoplasm, large nuclei, and prominent nucleoli in more than 90% of tumor cells. Triple-negative apocrine carcinoma is a rare molecular subtype that constitutes less than 1% of triple-negative breast cancers and is characterized by negative expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor, with positive expression of androgen receptor. CASE PRESENTATION: We report a case of a 45-year-old Syrian female who presented to our hospital due to a painless palpable mass in her left breast. Following physical and radiological examinations, an excisional biopsy was performed. Microscopic examination of the specimen followed by immunohistochemical staining revealed the diagnosis of a triple-negative apocrine carcinoma. CONCLUSION: Triple-negative apocrine carcinoma is an extremely rare neoplasm that must be considered in the differential diagnoses of breast lesions through detailed clinical, histological, and immunohistochemical correlations. In our manuscript, we aimed to present the first case report of a Syrian female who was diagnosed with a triple-negative apocrine carcinoma, aiming to highlight the importance of detailed clinical, histological and immunohistochemical correlations with a detailed review of diagnostic criteria, molecular characteristics, and treatment recommendations.

A large ovarian steroid cell tumor-not otherwise specified with a unique combination of benign and malignant features as a challenging cause of oligomenorrhea and hirsutism in a 21-year-old Syrian female: a case report.

BACKGROUND: Ovarian steroid cell tumors represent a rare category of sex cord-stromal tumors that constitute less than 0.1% of all ovarian tumors. These neoplasms are classified into three main subtypes according to the cell of origin: Leidyg cell tumors, stromal luteomas, and steroid cell tumors not otherwise specified (SCTs-NOS). The latter subtype is defined as a neoplasm of an uncertain lineage that mostly affects middle-aged women, whereas it's rare in younger ages. CASE PRESENTATION: We report a case of a 21-year-old virgin female who presented to our hospital with complaints of mild abdominal pain, hirsutism, and oligomenorrhea for more than a year. Before her current admission, the patient had attended an external gynecologic clinic where she had been prescribed oral contraceptives to regulate her periods. Nevertheless, on presentation to our institution, physical examination revealed abdominal tenderness with a palpable pelvic mass and mild hirsutism in the thigh. Ultrasonography demonstrated a large left ovarian mass measuring 154 × 104 mm, and compressing the uterus. Therefore, a unilateral salpingo-oophorectomy was performed, and interestingly, pathologic examination of the large aforementioned mass alongside with immunohistochemical correlation revealed the diagnosis of a large ovarian steroid cell tumor-not otherwise specified with a unique combination of benign and malignant features. CONCLUSIONS: Although ovarian steroid cell tumors represent a rare category, they must be considered in the differential diagnosis for mild virilization symptoms in young females due to the importance of early diagnosis and management. In this manuscript, we aimed to present the first case report from Syria that highlights the crucial role of detailed morphological examination for challenging cases despite the difficulties in differential diagnosis, and the absence of ancillary techniques. Furthermore, we managed to discuss a brief review of diagnostic methods, histological characteristics, and treatment recommendations.

A case report of coexisting breast cancer with peritoneal, cutaneous tuberculosis, and potential Pott's disease: therapeutic and diagnostic challenges.

Introduction: Breast cancer affects one in eight women during their lifetime; it may coincide with other diseases due to its high prevalence. Different pathologies that occur simultaneously with breast cancer, or later during its course, lead to multiple interactions with cancer and have a significant impact on its management. Presentation of case: A 58-year-old Syrian female was admitted to our hospital for compliant of abdominal distension. Following complete examination, obtained biopsies confirmed the diagnosis of peritoneal tuberculosis. At a subsequent time, she suffered back pain and the computed tomography showed vertebral lesion with breast mass that was diagnosed as invasive lobular carcinoma (ILC) of the left breast. Vertebral lesion that appeared on radiologic assessment was diagnosed as cancer metastasis. However, the interaction of this metastasis with the proposed management diverted the attention towards its non-cancerous entity. Five months after completing the chemotherapy, biopsies revealed the recurrence of triple-negative (ER-, PR-, HER2- neu-) ILC of the breast. Ultimately, the patient was followed up for an overall duration of 4 years. Discussion: Latent tuberculosis infections may be activated by chemotherapy regimens that suppress immunity. Therefore, initial management of tuberculous infection is preferred when it coexists with cancer. Conclusion: Breast cancer is common and may co-present with other diseases, which, in some cases, produce mimicking lesions that alter its diagnosis. Pott's disease, albeit a rare entity, has shown a resurgence in developed countries and should be considered in the differential diagnosis of vertebral lesions in patients with breast cancer.

Poorly differentiated thyroid carcinoma arising from substernal goiter: a case report.

Introduction and importance: Poorly differentiated thyroid carcinomas represent a rare heterogeneous group of malignant tumors that constitute ~2-4% of all thyroid neoplasms. Substernal goiter (SG) is defined as an enlargement of the thyroid gland that is located below the thoracic inlet. Malignant neoplasms arising from a SG were reported in only 2-3% of cases.This case report has been reported in line with the Surgical CAse REport (SCARE) Criteria.21. Case presentation: This article presents a 54-year-old Syrian female who presented at our institution due to dysphagia, dyspnea, cervical swelling, and loss of appetite. Following clinical and radiological examinations, total thyroidectomy with lymph node dissection was performed. Microscopic examination revealed an infiltrative growth pattern of insular, trabecular, and solid formations of epithelial cells with scant eosinophilic cytoplasm, hyperchromatic nuclei, and bizarre mitotic figures with areas of necrosis. Subsequently, the final diagnosis was confirmed as a multifocal poorly differentiated thyroid carcinoma arising from a SG. Clinical discussion: The heterogeneity of histologic features of poorly differentiated thyroid carcinoma represents a diagnostic challenge. Diagnosis of poorly differentiated thyroid carcinomas is based on the Turin Criteria, which highlights histopathological features. Computed tomography plays a major role in SG for further evaluation. Conclusion: In this manuscript, the authors aimed to present a unique case report with challenging diagnostic features including the rapid development of an infiltrative poorly differentiated thyroid carcinoma from a SG highlighting the importance of a detailed histopathological examination of thyroid nodules in the absence of significant medical history.

Incidental discovery of unilateral hydronephrosis unveiling psoas major desmoid-type fibromatosis in a 24-year-old male: A case report with a 5-year follow-up.

RATIONALE: Desmoid-type fibromatosis (DTF), also known as aggressive fibromatosis, is a rare neoplasm originating from the fascial or musculoaponeurotic tissues. While benign and characterized by slow growth, it exhibits local aggressiveness and lacks specific clinical characteristics. However, in a considerable percentage of patients, it could be asymptomatic and discovered by accident during routine clinical examinations. Only a few cases of DTF arising from the psoas major muscle have been reported in the medical literature. PATIENT CONCERNS: A 24-year-old male, asymptomatic and without significant personal or family medical history, was diagnosed with grade 2 hydronephrosis by abdominal ultrasonography during a routine physical examination. This diagnosis was made 15 days after undergoing uncomplicated open-heart surgery to repair an atrial septal defect. DIAGNOSIS: Intravenous pyelogram revealed hydronephrosis with dilation of the pelvicalyceal system. Ureteroscopy ruled out any intrinsic lesions of the ureter. Contrast-enhanced computed tomography identified a 3.5 × 2 × 5.2 cm mass in the retroperitoneum, closely associated with the psoas muscle and enveloping the ureter adjacent to the iliac artery. Postoperative pathological analysis confirmed a definitive diagnosis of sporadic DTF. INTERVENTIONS: The patient underwent exploratory abdominal surgery, during which the tumor was resected without any intraoperative complications. RESULTS: After close monitoring over a 5-year follow-up period, which included periodic physical examinations, magnetic resonance imaging, and ultrasonography, no local recurrence was detected. LESSONS: Achieving an accurate preoperative diagnosis presents a challenge in cases involving retroperitoneal tumors originating from the psoas major muscle and encasing the ureter. However, the insertion of a double J stent is deemed a crucial step in the surgical process, facilitating the dissection and isolation of the ureter from the tumor while preserving kidney function.

Spinal intradural extramedullary cavernoma: A case report.

INTRODUCTION: Cavernomas are rare vascular lesions that can occur anywhere along the neuraxis. However, they are most commonly found in the cerebral hemispheres. Spinal cavernomas are more uncommon and intradural extramedullary cavernomas are the most uncommon as they constitute only 3 % of spinal cavernomas. PRESENTATION: A 36-year-old female presented to our neurosurgical clinic with a history of back pain radiating to the left side of the chest with left lower extremity paresthesia and ataxia without urinary disturbance. Neurological exam showed left-sided hypoesthesia below the T9 dermatome in addition to increased patellar and Achilles reflexes on the left side. MRI showed a homogeneous intradural extramedullary mass which was hyperintense on T1 and hypointense on T2 and it was surgically resected. Pathological examination confirmed the diagnosis of intradural extramedullary cavernoma. DISCUSSION: Intradural extramedullary cavernomas are extremely rare lesions that arise within the area located between the inner surface of the dura and the pial surface of the spinal cord. Up until 2022 only 40 cases of intradural extramedullary cavernomas were reported in the literature. MRI is the preferred imaging modality and pathology is the golden standard for diagnosis. Surgical resection showed very promising results and it is considered the golden standard for treating this condition. However, surgery should be performed urgently to give an optimal outcome. CONCLUSION: Clinicians should consider this condition in their differential diagnoses when faced with progressive spinal root compression symptoms, sudden onset myelopathy, or progressive subarachnoid hemorrhage.

Secondary neoplasm to non-hodgkin lymphoma treatment manifesting as a cancer of unknown primary: the first case in literature.

Introduction: Cancer of unknown primary (CUP) is a tumour metastasis with no detectable primary origin. A secondary neoplasm (SN) is defined as a tumour secondary to a prior tumour treatment and has no histological relation to that primary tumour. Case presentation: The authors report a case of a 72-year-old female patient who presented with back pain and had a history of non-Hodgkin lymphoma (NHL) treated with RCHOP 12 years ago. MRI showed a compression fracture in T5 and T7 vertebrae, while the PET/computed tomography (CT) only showed hypermetabolic lytic bone lesions in these vertebrae. Pathological examination of a biopsy of these lesions suggested metastatic breast cancer, but the mammography was normal. The above clinical description indicates that our case is a SN to RCHOP treatment manifested as a cancer of unknown origin. Discussion: CUP is diagnosed when all screening procedures fail to find the original tumour. On the other hand, the literature showed that RCHOP treatment of non-Hodgkin lymphoma has a 0.68% chance of causing a SN. After an extensive literature search, we found that our case, which has the combination of both CUP and SN, is the first documented case. Conclusion: This case suggests that cancer patients who received chemical or radiological treatment should be screened more carefully on the long term as it is possible to developed secondary neoplasms without a primary tumour in areas difficult to diagnose with traditional screening tools.

Atypical teratoid/rhabdoid tumor of the central nervous system: Clinicopathological features of two challenging cases.

INTRODUCTION: Atypical Teratoid/Rhabdoid Tumor (AT/RT) is a rare aggressive neoplasm that mainly affects the pediatric population with a peak incidence in the first two years of life and a slight male predominance, whereas presentation of this neoplasm in older ages is extremely rare. CASE PRESENTATION: Herein, we present two cases of AT/RT. In the first case, a 9-year-old female presented with diplopia, dizziness, headache, and morning vomiting. CT Scan of the head demonstrated a heterogeneous mass in the left frontal-parietal region with vasogenic edema and midline deviation. In the second case, a 57-year-old female presented with severe generalized headache, numbness, and tingling in the right hand. MRI revealed a lobulated cystic mass in the right occipitotemporal region, with surrounding edema compressing the left lateral ventricle and causing a midline shift to the left, and enlargement of the right lateral ventricle. In both case, histopathological and immunohistochemical examinations revealed the diagnosis of Atypical teratoid/Rhabdoid tumors. CLINICAL DISCUSSION: Microscopic examination demonstrated the proliferation of medium-sized to large cells with abundant eosinophilic cytoplasm, large vesicular eccentric nuclei, and conspicuous nucleoli with areas of necrosis and hemorrhage, thus confirming the diagnosis with adequate immunohistochemical staining. The first patient developed signs of recurrence and passed away six months later, whereas in the second case, the 57-year-old female received radiotherapy for 6 weeks before being put on chemotherapy. CONCLUSION: Despite the challenges facing the diagnosis of this aggressive neoplasm, we managed to present our cases with detailed histopathological and immunohistochemical examinations.

Clival chordoma presenting with isolated unilateral cranial nerve XII palsy: A case report.

INTRODUCTION: Chordomas are rare malignant neoplasms that can originate anywhere along the cerebrospinal axis. However, they are most commonly found in the spine, cranium, and sacrococcygeal region. Chordomas can manifest differently depending on their location and most symptoms are a result of local invasion. We present a rare case of intracranial clival chordoma that manifested as isolated unilateral cranial nerve XII (CN XII) palsy. PRESENTATION: A 53-year-old male presented to the neurosurgical clinic with headaches, dysarthria, and pharyngeal pain. Neurological examination showed left-sided atrophy of the tongue. MRI scan showed an infiltrative lesion in the clivus which was hypointense on T1 and hyperintense on T2. The lesion was treated surgically however full resection was not achieved. Pathological examination and subsequent immunohistochemical staining confirmed the diagnosis of chordoma. DISCUSSION: To our knowledge, there have been only two reported cases of clival chordoma that presented with isolated CN XII palsy which manifested clinically as dysarthria and unilateral atrophy of the tongue. This makes our case the third reported case of clival chordoma that presented with isolated CN XII palsy. CONCLUSION: We report a rare case of clival chordoma that presented with isolated left CN XII palsy. Physicians should consider clival chordomas in their differential diagnoses when faced with isolated unilateral CN XII palsy. Surgical resection combined with adjuvant radiotherapy remains the preferred treatment protocol.

Advances in early detection of non-small cell lung cancer: A comprehensive review.

BACKGROUND: Lung cancer has the highest mortality rate among malignancies globally. In addition, due to the growing number of smokers there is considerable concern over its growth. Early detection is an essential step towards reducing complications in this regard and helps to ensure the most effective treatment, reduce health care costs, and increase survival rates. AIMS: To define the most efficient and cost-effective method of early detection in clinical practice. MATERIALS AND METHODS: We collected the Information used to write this review by searching papers through PUBMED that were published from 2021 to 2024, mainly systematic reviews, meta-analyses and clinical-trials. We also included other older but notable papers that we found essential and valuable for understanding. RESULTS: EB-OCT has a varied sensitivity and specificity-an average of 94.3% and 89.9 for each. On the other hand, detecting biomarkers via liquid biopsy carries an average sensitivity of 91.4% for RNA molecules detection, and 97% for combined methylated DNA panels. Moreover, CTCs detection did not prove to have a significant role as a screening method due to the rarity of CTCs in the bloodstream thus the need for more blood samples and for enrichment techniques. DISCUSSION: Although low-dose CT scan (LDCT) is the current golden standard screening procedure, it is accompanied by a highly false positive rate. In comparison to other radiological screening methods, Endobronchial optical coherence tomography (EB-OCT) has shown a noticeable advantage with a significant degree of accuracy in distinguishing between subtypes of non-small cell lung cancer. Moreover, numerous biomarkers, including RNA molecules, circulating tumor cells, CTCs, and methylated DNA, have been studied in the literature. Many of these biomarkers have a specific high sensitivity and specificity, making them potential candidates for future early detection approaches. CONCLUSION: LDCT is still the golden standard and the only recommended screening procedure for its high sensitivity and specificity and proven cost-effectiveness. Nevertheless, the notable false positive results acquired during the LDCT examination caused a presumed concern, which drives researchers to investigate better screening procedures and approaches, particularly with the rise of the AI era or by combining two methods in a well-studied screening program like LDCT and liquid biopsy. we suggest conducting more clinical studies on larger populations with a clear demographical target and adopting approaches for combining one of these new methods with LDCT to decrease false-positive cases in early detection.

Urachal carcinoma initially presenting only as a liver metastasis, a diagnostic and therapeutic challenge: first case in literature.

Introduction: Urachal carcinomas are uncommon malignant neoplasms comprising only 0.01% of all adult cancers. Most patients were aged from 58 to 64 years at diagnosis with 60 years being the median. It usually metastasizes to the lungs (22%), bones (22%), and liver (16%). Presentation: We report a case of a 71-year-old female patient who initially presented with two large liver masses and a small nodule on the anterior side of the bladder. The symptoms were nonspecific with abdominal discomfort. The final diagnosis of urachal adenocarcinoma was finalized with a biopsy of the bladder mass. The patient initially received six doses of FOLFOX6 without improvement and then Gem-Carbo, showing improvement after six doses. Finally, the patient received two doses of FOLFIRI-B with no response and kept deteriorating and died after 19 months of treatment. Discussion: About 90% of patients are symptomatic and hematuria is the most typical presenting symptom at diagnosis. The low incidence and the histopathologic similarities to adenocarcinoma from various sources pose a difficulty in recognizing the tumor. Our study presents the only case of a urachal carcinoma first manifesting with abdominal mass resulting from liver metastasis with no prior symptoms of urological origins. Also, our study presents the first attempt of using FLOFIRI-B to treat metastatic UraC. Conclusion: This case highlights the necessity for clinicopathological correlation to make the correct diagnosis and the challenges in the treatment which urges the need for further research to identify more effective treatment strategies for this rare cancer.

Primary spinal oligodendroglioma with intracranial extension: a case report.

Introduction: Primary spinal cord oligodendrogliomas (PSO) are sporadic tumors that arise from oligodendrocytes in the central nervous system (CNS). They can affect adults and children and make up about 2% of all intramedullary (IM) spinal tumors. Here, the authors present the second case in the literature of a primary spinal oligodendroglioma with intracranial extension. Presentation: A 28-year-old right-handed female presented to our emergency room severely malaised with left-sided hemiparesis, numbness, tingling, and urinary retention with positive Babinski and negative Hoffmann. MRI showed a widespread heterogeneous mass extending from the medulla to C7 with syringomyelia inferior to the mass. The mass was removed surgically, and her neurological condition improved rapidly. The gross, pathological exams, and immunohistochemistry confirmed the diagnosis of oligodendroglioma. Discussion: Up until 2017, there have been 60 documented cases of PSO in the literature and we have found two more cases in our search between 2017 and 2023. Also, there has been only one case recorded with an intracranial extension, making our case the 63rd PSO case and the second one with cranial extension. Conclusion: The golden standard for imaging is MRI. Surgical excision is the main treatment in the literature. Single-stage laminectomy showed promising results and surgical resection was the critical intervention to which the patient responded. This matches what was stated in the literature that surgery is the primary mode of treatment in PSO patients.

Primary left intrathoracic extrapulmonary trans-diaphragmatic hydatid cyst causing eventration: first case in literature.

Hydatidosis is a zoonotic parasitic disease caused by the cystic stage of Echinococcus species. Intrathoracic extrapulmonary hydatid cysts causing eventration are very rare. Here, we report a case of a 62-year-old female who presented with chest pain, intermittent coughing, general weakness, and fever. On auscultation, there were diminished respiratory sounds at the base of the left lung. A computed tomography scan showed a cystic formation with an ambiguous location involving the left lower thorax and the left hypochondrium. Complete surgical resection is the standard treatment for intrathoracic extrapulmonary hydatid cysts. Due to the direct bordering of the cyst with the pericardium in the left cadiophrenic angle, a cystotomy and evacuation of the cystic cavity were performed, followed by washing it with povidone and hyperosmolar saline. The location of the hydatid cyst has an important role in determining the surgical approach, as the unusual location could affect the possibility of radically removing the cyst.

Secondary amenorrhea as the first presentation of Krukenberg tumor arising from the gastroesophageal junction in a 34-year-old woman: A case report.

INTRODUCTION: Krukenberg tumors account for 9 % of metastatic ovarian tumors, they usually originate from the stomach and colon and are microscopically characterized by the presence of mucus-filled signet-ring cells. Krukenberg tumor originating from the gastroesophageal junction is extremely rare, which limits establishing proper diagnosis and management. PRESENTATION OF CASE: A 34-year-old women presented with a complaint of amenorrhea, ultrasonography showed bilateral ovarian masses, pathological studies revealed Krukenberg tumor, immunohistochemistry of the tumor was positive for (CK1, and CK20). Upper GI endoscopy revealed the primary lesion located at the inferior esophagus and extending to the cardia. Despite marked improvement after introducing a chemotherapy regimen of oxaliplatin, calcium folinate and fluorouracil, the patient refused to complete her therapeutic course and died 5 months after discontinuation. DISCUSSION: Krukenberg tumor may be asymptomatic but may also manifest as pelvic pain, bloating, and menstrual cycle abnormalities. Immunohistochemistry of Krukenberg tumor is mandatory to determine the primary tumor. Positivity of CK1, CK20 and negativity of CK7 indicates the gastrointestinal origin of the tumor. Different choices are available for the management of Krukenberg tumor but it still has a poor prognosis with an average survival rate of 14 months. CONCLUSION: Krukenberg tumor from the esophagus is rare and still enigmatic in terms of management. In this article, we aim to draw attention into possible presentations of the tumor by providing the first case in Syria of Krukenberg tumor originating from the esophagus and presenting as secondary amenorrhea and bilateral adnexal masses.

The correlation between gut microbiota and both neurotransmitters and mental disorders: A narrative review.

The gastrointestinal tract is embedded with microorganisms of numerous genera, referred to as gut microbiota. Gut microbiota has multiple effects on many body organs, including the brain. There is a bidirectional connection between the gut and brain called the gut-brain-axis, and these connections are formed through immunological, neuronal, and neuroendocrine pathways. In addition, gut microbiota modulates the synthesis and functioning of neurotransmitters. Therefore, the disruption of the gut microbiota in the composition or function, which is known as dysbiosis, is associated with the pathogenesis of many mental disorders, such as schizophrenia, depression, and other psychiatric disorders. This review aims to summarize the modulation role of the gut microbiota in 4 prominent neurotransmitters (tryptophan and serotonergic system, dopamine, gamma-aminobutyric acid, and glutamate), as well as its association with 4 psychiatric disorders (schizophrenia, depression, anxiety disorders, and autism spectrum disorder). More future research is required to develop efficient gut-microbiota-based therapies for these illnesses.

The microbiota-gut-brain axis and three common neurological disorders: a mini-review.

Neurological disorders are an important cause of disability and death globally. Recently, a large body of research shows that the gut microbiome affects the brain and its conditions, through the gut-brain axis. The purpose of this mini-review is to provide a brief overview of the relationship between the microbiota-gut-brain axis in three neurological disorders: epilepsy, Parkinson's disease, and migraine. The authors chose these three disorders because of their burdensome and great effect on health care. We live on a microbial planet. Before humans, microorganisms existed for a hundred million years. Today, there are trillions of these microbes living in our bodies, it is called human microbiota. These organisms have a crucial role in our homeostasis and survival. Most of the human microbiota live in the gut. The number of gut microbiota is much more than the number of body cells. Gut microbiota has been regarded as a crucial regulator of the gut-brain axis. The discovery of the microbiota-gut-brain axis is described as a major advancement in neuroscience because it influences the pathophysiology of several neurological and psychiatric disorders. From this, more studies of the microbiota-gut-brain axis are needed in the future, to provide a better understanding of brain disorders and so that better treatment and prognosis.

Pseudoaneurysm of the external carotid artery following parotitis: a case report.

Pseudoaneurysms of the external carotid artery of nontraumatic causes are very rare; those of infectious causes in adults are also quite unusual and are often preceded by bacteremia. Infection-related cases such as the one described here are scarce in the literature since the complication is not often calculated or expected. We present a case report of an elderly female patient who, after dental treatment and parotitis, noticed a mass behind the right mandible. After examination, the case was diagnosed as a pseudoaneurysm of the external carotid artery of an infectious cause. Management could be by surgical intervention, but the high positioning of the pseudoaneurysm and the age of the patient were contraindications. The choice was made to avoid surgery and keep the patient under long-term follow-up; no increase in its mass was observed after 3 years of follow-up.

Xanthogranulomatous pyelonephritis mimicking renal cell carcinoma: a case report.

Xanthogranulomatous pyelonephritis (XGPN) is a rare, serious, and chronic inflammatory disorder of the kidney characterized by a destructive process that invades the renal parenchyma, which is most commonly associated with urinary tract obstruction and infection. It affects women more often than men. Case presentation: Herein, the authors report a case of a 48-year-old male presented to their hospital with complaints of malaise, fever, chills, left flank pain, and a history of a staghorn calculus in the renal pelvis, which was removed by surgery 7 years ago. Ultrasonography and computed tomography scans showed an enlarged left kidney with cystic formation and pelvicalyceal system dilation with the presence of multiple large stones. The renogram showed a dysfunctioning left kidney. An open radical left nephrectomy was performed. Renal cell carcinoma (RCC) was suspected in both the gross and microscopic examinations. The immunohistochemistry was the decisive factor in confirming the diagnosis of XGPN. Clinical discussion: Preoperative and postoperative diagnosis of XGPN can sometimes be difficult due to diverse differential diagnoses. The misinterpretation of 'foam cells' as 'clear cells' consistent with RCC is the most important diagnostic challenge for pathologists. Conclusion: The unusual findings of this case report suggest a careful evaluation of patients with a renal cystic mass, that can be misdiagnosed as a RCC. A combined computed tomography scan evaluation together with histopathology and immunohistochemistry are essential for a correct diagnosis of this rare renal entity.

Coexistence of a huge Brenner's tumour and mucinous cystadenoma in a 62-year-old female: a case report from Syria.

The coexistence of a benign Brenner tumour and a mucinous cystadenoma is rare, and their relationship and origin are still enigmatic and challenging. Case presentation: In this manuscript, the authors report a case of a 62-year-old nulliparous Syrian woman who presented with severe abdominal distension, which was followed by laparotomy and the excision of a 25×20 cm-cyst; its pathological examination confirmed a benign Brenner's tumour and mucinous cystadenoma. Clinical discussion: Ovarian Brenner and mucinous are usually benign and can rarely grow asymptomatically to very big sizes. Herein, the authors aim to emphasize the importance of excluding malignancy by pathology examination. Conclusion: Walthard cell nests undergo metaplasia to give rise to different kinds of Brenner and mucinous neoplasm formations according to their genetic alterations. This paper adds to the available literature, which is still poor, by providing evidence of the first case of this rare combination from Syria with a review of different theories of origin and differential diagnoses. More studies directed towards exploring this combination's genetic origin are needed to boost our understanding of ovarian tumours in general.