Primary anterior visual pathway germinoma in a 13-year-old boy: A case report.

Background: Primary optic nerve and chiasmal germinomas are very rare. These lesions can commonly be mistaken for optic pathway gliomas based on imaging alone. It is radiosensitive and cured in most of the cases. Case Description: We report a rare case of a 13-year-old boy with primary bilateral optic nerves and chiasmal germinoma who underwent partial surgical resection followed by radiotherapy. Follow-up brain imaging after two months post-radiotherapy showed interval regression of the tumor. Our literature review identified that 12 reported cases of primary anterior visual pathway germinoma had been reported to regress significantly post-radiotherapy alone or with chemotherapy. Conclusion: Histologic correlation is essential for appropriate treatment, alleviating symptoms, and avoiding irreversible vision loss.

A Pathology Experience of Posttransplant Lymphoproliferative Disorder From One Tertiary Hospital: Pathology Concepts and Diagnostic Approach.

BACKGROUND: Solid organ transplantation and bone marrow/hematologic stem cell transplantation recipients face a heightened risk of developing malignancies or cancer as a result of immunosuppression. Posttransplant lymphoproliferative disorders (PTLD) are a range of disorders from benign lymphoid growth to lymphoma found post-transplant. Risk factors for PTLD include high immunosuppressive use and oncogenic effects of Epstein-Barr virus (EBV). There is a lack of comprehensive clinical and pathological documentation of PTLD cases among Saudi patients, and the available data are limited to a few case reports. As a result, a deeper understanding of this disease requires more clinicopathological information. MATERIAL AND METHOD: In this review, we share our insights on cases diagnosed with PTLD at King Faisal Specialist Hospital and Research Center, a prominent tertiary center in the western region of Saudi Arabia, from 2005-2023. RESULT: We have diagnosed a total of 14 cases of PTLD in our department, with an age range spanning from 3 to 62 years. These diagnoses were made based on biopsies or tumor resection procedures. The survival rate of patients is believed to be influenced by multiple factors, including histology, tumorigenesis, disease biology, and clinical stage. Additionally, Kaplan-Meier curve analysis indicates that female patients tend to have a higher estimated survival rate compared to males. CONCLUSION: PTLD diagnosis and therapy have greatly improved in the past 20 years. PTLD is treated with reduced immunosuppression, rituximab, chemotherapy, adoptive therapy, surgery, antiviral therapy, and radiotherapy. In this study, we present our experience from a large tertiary center in the western region of Saudi Arabia. Moreover, we will go through etiology, clinical features, and pathologic morphology along with the corresponding genetics, prevention, and valid treatment options.

Extracranial Medulloblastoma With Myogenic Differentiation: Report of a Rare Event.

Medulloblastoma accounts for nearly 10% of childhood primary central nervous system (CNS) malignancies. However, it is rare in adults. Extracranial metastasis is commonly documented to involve bones but rarely involves lymph nodes. Herein, we present an unusual case of primary CNS medulloblastoma in an adult patient with extracranial metastasis to a lymph node, which exhibits a myogenic differentiation. To the best of our knowledge, this is the fourth reported case of medulloblastoma in an adult with extracranial metastasis to the lymph node and the first reported case of extracranial metastatic medulloblastoma with myogenic differentiation that involves a lymph node.

Variants of Human Mucin Genes in Clear Cell Renal Cell Carcinoma and their Potential Prognostic and Predictive Values.

BACKGROUND: There is no reliable prognostic and predictive biomarkers for clear cell renal cell carcinoma (cc-RCC). METHODS: DNA from 47 cc-RCC tissue samples were sequenced using next generation sequencing and a customized gene panel testing for tumor-driver genes including 19 Mucin genes. RESULTS: Distinctive variants in 12 Mucin genes were present in all samples. These genes are: MUC2, MUC3A, MUC4, MUC5AC, MUC5B, MUC6, MUC7, MUC12, MUC16, MUC17, MUC19, and MUC22. The numbers of distinctive and non-distinctive variants were counted for each sample. The median number of variants was 455. High variant number (HVN) (>455) was associated with shorter overall survival compared to low variant number (≤455) [Median 50 months vs. not reached; P=0.041]. In the 11 patients who received anti-angiogenic tyrosine kinase inhibitors (TKIs), HVN was associated with a trend of shorter progression free survival. CONCLUSION: Alterations in Mucin family genes are common in ccRCC. HVN is associated with worse prognosis and may predict decreased benefit from anti-angiogenic TKIs. KEY WORDS: Mucin; Variants; Renal cell carcinoma; Biomarker; Tyrosine kinase inhibitors.

Adenomatous hyperplasia of rete testis diagnosis on testicular biopsy for primary infertility: A case report.

Adenomatous hyperplasia of rete testis is a rare non-neoplastic proliferation of rete testis epithelium. Mostly as an incidental finding in orchiectomy specimen for cryptorchidism and germ cell tumors. However, AHRT in testicular biopsies is rarely reported in the literature. The pathogenesis of AHRT is not fully understood yet. AHRT usually arises near the mediastinum and septal portion of the rete testis. Herein, we report an interesting finding of AHRT in a testicular biopsy performed for infertility workup. Practicing pathologists must be aware of this entity and the differential diagnosis as it might pose a diagnostic challenge during histological evaluation.

Compound Heterogeneous Sickle Cell-B+ Thalassemia Incidentally Discovered Through Cytological Examination of a Fine-Needle Aspiration Specimen from an Aneurysmal Bone Cyst in a Young Child: A Case Report.

Sickle cell beta-thalassemia (S/ß) is a rare inherited variant of sickling disorders, usually occurring due to the inheritance of two abnormal genes, namely, the sickle cell gene, and the beta-thalassemia gene. There are two types of sickle cell ß-thalassemia: (S/ß+) and (S/ß0), based on a decrease or complete absence of beta-globin synthesis, respectively. Skeletal complications, such as osteonecrosis, osteomyelitis, and septic arthritis, are well-known sequelae in sickle cell patients due to vaso-occlusive events. Nevertheless, the occurrence of aneurysmal bone cysts in patients with sickle cell hemoglobinopathy is an exceptional phenomenon. Herein, we report a case of a young boy who presented with nonspecific clinical symptoms over a few years. The patient was referred to our institution as a case of short stature with recurrent joint pain. A clinical workup was done and an aneurysmal bone cyst (ABC) of the left humerus was discovered radiologically with incidental detection of sickle cells through cytological evaluation of the cyst fluid. Further clinical investigation, including molecular and additional laboratory tests, confirmed the diagnosis of compound heterogeneous sickle cell-B+ thalassemia. Unfortunately, neither was the underlying pathology detected nor was the precise clinical diagnosis attained at the outside primary healthcare facility.

Solid Pseudopapillary Neoplasm of the Pancreas: A Clinicopathological Study of 12 Cases With Emphasis on Diagnostic Pitfalls.

INTRODUCTION: Solid pseudopapillary neoplasm of the pancreas (SPNP) is a rare primary neoplasm with distinct clinicopathological features. The tumor most commonly occurs in younger (premenopausal) women and is typified by low malignant potential and an excellent overall prognosis. METHODS: A retrospective search over 20 years at two referral tertiary care institutions (King Faisal Hospital and Research Center and King Abdulaziz University Hospital, Jeddah, Kingdom of Saudi Arabia) revealed 12 female patients diagnosed with SPNPs. The reslts of ancillary studies performed at the time of diagnosis were also reviewed and placed in the context of current recommendations. RESULTS: The clinical and pathological findings were reviewed. All patients were females, aged 18 to 30 years. Eight patients presented with abdominal pain, of which two experienced significant weight loss, and four presented with abdominal mass/discomfort. The tumor size ranged from 1.5 and 15 cm. Two cases were initially diagnosed as neuroendocrine tumors (NETs). One of the cases presented as a multifocal disease. All patients were treated surgically with a follow-up period between one and 11 years. Only one patient presented with peritoneal metastasis after seven years of follow-up, but generally, all are doing well. CONCLUSIONS: We have analyzed 12 SPNP cases in our population over 20 years (2001-2021) in this study. In brief, SPNP is a low-grade malignant potential tumor. Even though SPNP is a recognized entity, diagnostic challenges can arise particularly in the setting of limited sampling. Pathologists must be aware of the classic morphological features of SPNP and the characteristic profile of immunohistochemistry and be able to differentiate SPNP from other mimickers, especially well-differentiated NETs of the pancreas, and ultimately to avoid misdiagnosis and unnecessary oncologic treatment. Adequate surgical resection with negative margins is associated with an excellent outcome.

Embryonal tumor with multilayered rosettes; rare pediatric CNS tumor. A case report and review of literature.

Embryonal tumor with multilayered rosettes (ETMR), C19MC-altered is a newly designated entity of the embryonal tumors of the central nervous system (CNS) according to the 2016 WHO classification system of CNS. Characteristically, these tumors are newly defined based on their specific molecular genetic amplification in chromosome 19q13.42 found at locus C19MC. To the best of our knowledge, we present the first reported case of ETMR in Saudi Arabian pediatric population. A 2-year-old boy presented to the hospital with generalized tonic-colonic seizure, vomiting, irritability, and inability to walk. Computed tomography (CT) scan showed a large left thalamic supratentorial brain tumor. The tumor measured 6.1 × 5.6 × 5.6 cm and was characterized by cystic changes, prominent vasculature, and calcifications. Histopathology, immunohistochemistry examination, and fluorescence in situ hybridization (FISH) analysis confirmed the diagnosis of ETMR. In addition to reporting this rare case, we provide a brief literature review, treatment options, patient outcome, and disease prognosis.

Tumor-to-Tumor Metastasis of Renal Cell Carcinoma to a Follicular Variant of Papillary Thyroid Carcinoma: A Case Report and Literature Review.

Renal cell carcinoma (RCC) is the most common renal malignancy. It has a variable clinical course with metastasis to unusual sites occurring months to years after the initial diagnosis. However, metastasis can also be the first presentation of RCC. Although relatively uncommon, the thyroid gland is the most common location for RCC metastasis in the head and neck region. Tumor-to-tumor metastasis is an exceedingly rare occurrence. Only 10 cases were reported of RCC metastasis to primary thyroid neoplasms. We present a case of clear cell RCC metastasizing to a follicular of variant papillary thyroid carcinoma (FVPTC) 14 years after the initial diagnosis of RCC. A review of similar reported cases revealed that the most common primary thyroid recipient of tumor-to-tumor metastasis of RCC was FVPTC. The rich lymphovascular network in FVPTC compared to other thyroid tumors, which may promote the deposition of metastatic tumor cells, might explain this predilection. Careful review of the clinical and radiological findings and checking for any history of malignancy when examining thyroid nodules is important for guiding further studies. Performing a targeted panel of immunohistochemical stains for any suspicious areas is also essential for the diagnosis of such unusual cases.

Para-testicular florid cystic müllerianosis in an elderly patient: Case report of a rare metaplastic change of tunica vaginalis with unusual clinical presentation (mass forming lesion).

Müllerian metaplasia/florid cystic Müllerianosis of the tunica vaginalis is one of the metaplastic changes described in the testis. Others include urothelial metaplasia, epidermoid metaplasia, and gastric metaplasia. Florid cystic Müllerianosis shares similar histo-morphological features and immunohistochemical profile with female counterpart endosalpingiosis. Herein, we report a case of para-testicular florid cystic Müllerianosis presented as a painless testicular mass in a 66-year-old male with normal tumor markers.

Phosphaturic Mesenchymal Tumor: A Case Report of a Rare Entity.

Phosphaturic mesenchymal tumor (PMT) is a rare entity that presents as a paraneoplastic syndrome that causes tumor-induced osteomalacia (TIO). Most of these cases were located in the extremities. We report a case of a phosphaturic mesenchymal tumor arising in the left upper thigh. The tumor was discovered during the clinical workup of a patient complaining of osteomalacia symptoms with multiple fractures.

Biweekly cetuximab in combination with capecitabine and oxaliplatin (XELOX) or irinotecan (XELIRI) in the first-line and second-line treatment of patients with RAS wild-type metastatic colorectal cancer.

Background: Oral capecitabine in combination with intravenous oxaliplatin (XELOX) or irinotecan (XELIRI) are acceptable substitutions to fully intravenous regimens. Biweekly (as opposed to weekly) cetuximab is more convenient when combined with biweekly chemotherapy. Here, we report the tolerability and efficacy of biweekly cetuximab in combination with biweekly XELOX or XELIRI in patients with RAS wild-type metastatic colorectal cancer (RAS-WT mCRC). Methods: Clinical data of consecutive patients with mCRC who received biweekly cetuximab (500 mg/m2) in combination with XELOX or XELIRI between January 2009 and May 2019 in the first- or second-line settings was extracted. Dosage of XEL (Capecitabine/XELODA) was 1,000 mg/m2 twice daily for 9 days, plus on day 1 oxaliplatin 85 mg/m2 or irinotecan 180 mg/m2. Treatment dose reduction and delay for ≥7 days was analysed as surrogates for toxicity. Extended RAS testing was performed in the context of this study for patients who received treatment based on limited KRAS-WT genotype. Results: Sixty one patients with RAS-WT mCRC fulfilled the eligibility criteria. XELOX was administered to 26 (42.6%) and XELIRI to 35 (57.4%) of patients. For all patients in the first-line setting, the objective response rate (ORR), median progression free survival (PFS) and median overall survival (OS) were 54%, 8 months and 25 months, respectively. The corresponding outcomes for the subgroup of patients who received first-line XELOX were 68%, 10 months and not reached, respectively. For all patients in the second-line setting, the ORR, PFS and OS were 50%, 7 months and 20 months, respectively. Chemotherapy components dose reduction and delays were observed in 18 (29.5%) and 25 (41%) patients, respectively. The corresponding frequencies for cetuximab were 3 (5%) and 31 (50.8%). Conclusion: Biweekly cetuximab in combination with XELOX or XELIRI is tolerable and effective. The addition of cetuximab to capecitabine and oxaliplatin is associated with favourable outcome.

Intra-testicular angioleiomyoma. A case report of a rare male urological entity.

Angioleiomyoma (vascular leiomyoma) is a common benign smooth muscle tumor, often affecting the soft tissue of the extremities, head, and neck regions. However, testicular involvement is an exceedingly rare event. Herein, we present an unusual case of testicular angioleiomyoma. To the best of our knowledge, this is the third reported case in English literature.

Profiling Activins and Follistatin in Colorectal Cancer According to Clinical Stage, Tumour Sidedness and Smad4 Status.

This study explored the roles of activins and follistatin in colorectal cancers. Paired malignant and normal colonic tissues were collected from archived paraffin-embedded (n = 90 patients) alongside fresh (n = 40 patients) specimen cohorts. Activin ß-subunits, follistatin and Smad4 mRNAs and proteins were measured by real-time PCR and immunohistochemistry (IHC). Mature activin-A, -B, -AB and follistatin proteins were measured by ELISA. Cancer tissues having ≤ the 20th percentile of the Smad4 IHC score were considered as low (L-S4) group. The Smad4-intact SW480 and Smad4-null HT29 colon cancer cell lines were treated with activins and follistatin, and cell cycle was analysed by flow cytometry. The cell cycle inducing (CCND1/CCND3) and inhibitory (p21/p27) proteins alongside the survival (survivin/BCL2) and pro-apoptosis (Casp-8/Casp-3) markers were measured by immunofluorescence. Thirty-nine patients had right-sided cancers (30%) and showed higher rates of L-S4 tumours (n = 17; 13.1%) alongside worse clinicopathological characteristics relative to left-sided cancers. The ßA-subunit and activin-A increased, whilst ßB-subunit and activin-AB decreased, in malignant sites and the late-stage cancers revealed the greatest abnormalities. Interestingly, follistatin declined markedly in early-stage malignant tissues, whilst increased significantly in the advanced stages. All activin molecules were comparable between the early stage right- and left-sided tumours, whereas the late-stage right-sided cancers and L-S4 tumours showed more profound deregulations. In vitro, activin-A increased the numbers of the SW480 cells in sub-G1 and G0/G1-phases, whereas reduced the HT29 cell numbers in the sub-G1 phase with simultaneous increases in the G0/G1 and S phases. The p21/p27/Casp-8/Casp-3 proteins escalated, whilst CCND1/CCND3/BCL2/survivin declined in the SW480 cells following activin-A, whereas activin-A only promoted p21 and p27 alongside reduced CCND3 in the HT29 cells. By contrast, activin-AB increased the numbers of SW480 and HT29 cells in Sub-G1 and G0/G1-phases and promoted the anti-cancer and reduced the oncogenic proteins in both cell lines. In conclusion, activins and follistatin displayed stage-dependent dysregulations and were markedly altered during the advanced stages of right-sided and L-S4 cancers. Moreover, the activin-A actions in CRC could be Smad4-dependent, whereas activin-AB may act as a Smad4-independent tumour suppressor protein.

Well-differentiated neuroendocrine tumors of the lower urinary tract: biologic behavior of a rare entity.

The spectrum of neuroendocrine (NE) tumors in the genitourinary tract ranges from the aggressive large and small cell carcinomas to the often benign paraganglioma and well-differentiated neuroendocrine tumor (WD-NET). At least 15 pure lower urinary tract (LUT) WD-NETs have been described. Owing to the rarity of WD-NET in the LUT and the limited number of reported cases, a better definition of their biologic long-term behavior is warranted. Herein, we aim to describe 10 new cases of WD-NET arising in the LUT and expand on follow-up findings. Ten consultation cases were identified and included 6 men and 4 women who ranged from 45 to 73 years of age. Seven cases arose in the bladder with one located in the bladder neck, 1 arose in the prostatic urethra, 1 arose in the female urethra, and 1 arose in the left ureteral orifice. All lesions were confined to the lamina propria, and tumor architecture was pseudoglandular in all cases. Associated cystitis cystica et glandularis was identified in 5 cases; urothelial papilloma and florid von Brunn's nests were found in 2 additional cases. Immunohistochemical staining for synaptophysin and chromogranin was diffusely positive in 9 cases and focal in 1 case, and the Ki-67 proliferation index was 5% or less in all tumors. Follow-up ranged from 37 to 137 months (mean = 82; median = 77), and there was no evidence of residual disease or recurrence in any of the 10 patients during the follow-up period.

Condyloma accuminatum of the male urethra: A case report.

Condyloma acuminatum is an anogenital lesion caused by the human papillomavirus infection. It is a common, sexually transmitted disease. It usually affects the external genitalia, while urethral and bladder involvement is uncommon. Human papillomavirus types are classified into three categories depending on their oncogenic potential: low risk (type 6, 11, 42, 43, 44, 59, 66, 68, and 70), intermediate-risk (type 30, 31, 33, 34, 35, 39, 40, 49, 51, 52, 53, 57, 58, 63, and 64) and high risk (type 16, 18, 45, and 56). High-risk and intermediate-risk human papillomavirus DNA types, together with other co-factors still to be defined, account for over 90% of anogenital pre-malignant and malignant tumours. Herein, we report a unique case of condyloma acuminatum positive for human papillomavirus -6 involving the penile urethra, presents as the primary and only site of the disease in a diabetic type-2 patient.

Collision Glial Neoplasms Arising in an Ovarian Mature Cystic Teratoma: A Rare Event.

Germ cell neoplasms represent around 20% of all ovarian tumors. They most frequently affect children and young adults. Mature cystic teratoma is a common benign ovarian neoplasm comprising about 95% and is made up of all three germ cell embryonic layers. By definition, mature cystic teratoma may be derived from any of the three germ cell lines. On the other hand, immature teratomas contain primitive neuroepithelial elements. However, it is quite uncommon in the English literature to have a neuroepithelial glial neoplasm arising in a mature cystic teratoma of an adolescent. Interestingly enough, all published cases described a single type of glial neoplasm arising in mature ovarian teratoma. Herein, the authors discuss a unique case of concomitant occurrence of two different glial neoplasms, namely pilocytic astrocytoma and subependymoma arising in an ovarian mature cystic teratoma. To the best of our knowledge, this is the first reported case with such a distinctive histopathologic finding.

Pulmonary alveolar microlithiasis: A report of two unique cases.

Pulmonary alveolar microlithiasis (PAM) is an inherited autosomal recessive disease. PAM is classically characterized by calcium phosphate deposition within alveolar airspaces due to SLC34A2 (solute carrier family 34 member 2) gene mutation located on chromosome 4p15.2. Such cellular genetic mutation would lead to a defect in the sodium-phosphate transporter channel located in alveolar epithelial cells type-II. Ultimately, it would result in a malfunction of alveolar epithelial cells and the failure of these cells to clear-up the released phosphorous particles in the cellular surfactant recycling. PAM is usually diagnosed in adulthood, frequently notable in the third and fourth decades of life, occasionally can be associated with more severe clinical presentation and radiological findings. Nevertheless, the disease could manifest itself in the pediatric age group, which either shows non-specific signs and symptoms or be exclusively asymptomatic. Histopathological examination is the gold standard for the PAM diagnosis. Genetic counseling and testing might benefit the patient's family members. Herein, we present 2 cases of PAM in the pediatric age group, along with their clinical history, presentation, radiological studies, and histopathology findings, as well as a brief literature review.

Neuroendocrine tumor of the kidney: Diagnostic challenge and successful therapy.

The management of gastrointestinal and pancreatic (GEP) neuroendocrine tumors (NETs) has evolved over the recent decade. Primary renal NETs are extremely rare as neuroendocrine cells are not recognized in the normal renal parenchyma. We report a case of primary renal NET characterized by the initial diagnostic challenges. Recurrent and metastatic disease was managed along the lines of management of GEP-NETs, leading to prolonged progression-free survival.

Gestational Trophoblastic Disease Presents as an Ectopic Tubal Pregnancy, a Rare Entity.

Ectopic molar pregnancy is an uncommon event in clinical practice. In this paper, we report a case of ectopic complete molar pregnancy in a 39-year-old lady who presented to the emergency department with lower abdominal pain, abdominal distention, and low-grade fever. Based on radiological and laboratory investigations, the differential diagnosis included ruptured ectopic pregnancy versus metastatic diseases. Ectopic hydatidiform molar pregnancies can occur at any extrauterine pelvic sites, yet more frequently affecting fallopian tubes. The histopathological examination remains the gold standard for the diagnosis.