PD-1 expression, among other immune checkpoints, on tumor-infiltrating NK and NKT cells is associated with longer disease-free survival in treatment-naïve CRC patients.

A variety of variables, such as microsatellite instability or inflammatory mediators, are critical players in the development and progression of colorectal cancer (CRC). Natural killer (NK) and natural killer T (NKT) cells are involved in the prognoses of CRC. Immunological components of the tumor microenvironment (TME) impact cancer progression and therapeutic responses. We report that CRC patients with higher frequencies of tumor-infiltrating PD-1+ NK and NKT cells had significantly longer disease-free survival (DFS) than patients with lower frequencies. In agreement with that, patients with higher frequencies of tumor-infiltrating PD-1- NK and NKT cells showed shorter DFS. There were no significant associations between tumor-infiltrating PD-1+TIM-3+, PD-1+TIGIT+, PD-1+ICOS+, PD-1+LAG-3+ NK cells, and PD-1+TIM-3+, PD-1+TIGIT+, and PD-1+LAG-3+ NKT cells with DFS. This study highlights the significance of PD-1 expression on tumor-infiltrating NK and NKT cells and its association with disease prognoses in CRC patients.

Associations of different immune checkpoints-expressing CD4+ Treg/ T cell subsets with disease-free survival in colorectal cancer patients.

There are different subsets of T regulatory cells (Tregs), orchestrating critical roles in the regulation of anti-tumor immunity in colorectal cancer (CRC). In this study, we report that a high frequency of circulating CD4+FoxP3+ Tregs was associated with poorer disease-free survival (DFS), while their higher frequencies in tumor-infiltrating CD4+ Tregs was associated with better DFS. We further investigated such associations with four Tregs/T cells expressing or lacking FoxP3 and Helios (FoxP3±Helios±). For the first time, we report that a high frequency of circulating CD4+FoxP3+Helios+ Tregs was associated with poorer DFS, while a high frequency of tumor-infiltrating CD4+FoxP3-Helios- T cells was associated with poorer DFS. In the four FoxP3±Helios± T cell subsets expressing any of the immune checkpoints (ICs) investigated, we found that a high frequency of CD4+FoxP3+Helios-PD-1+ Tregs in circulation was associated with worse DFS. We also found that high frequencies of FoxP3+Helios+CTLA-4+ Tregs, FoxP3+Helios-CTLA-4+ Tregs, and FoxP3-Helios+CTLA-4+ CD4+ T cells in circulation were associated with worse DFS. In contrast, high frequencies of CD4+TIM-3+ T cells, FoxP3+Helios+TIM-3+ Tregs, and FoxP3-Helios+TIM-3+ CD4+ T cells in circulation were associated with longer DFS. Our data show that certain CD4+ Treg/T cell subsets could serve as independent predictive biomarkers in CRC patients. Identification of the exact subpopulations contributing to clinical outcomes is critical for prognoses and therapeutic targeting.

Transcriptome of CD8+ tumor-infiltrating T cells: a link between diabetes and colorectal cancer.

There is an increased risk of colorectal cancer (CRC) development in patients with non-insulin-dependent type 2 diabetes. CD8+ T cells have been implicated in diabetes and are crucial for anti-tumor immunity. However, transcriptomic profiling for CD8+ T cells from CRC diabetic patients has not been explored. We performed RNA sequencing and compared transcriptomic profiles of CD8+ tumor-infiltrating T lymphocytes (CD8+ TILs) in CRC diabetic patients with CRC nondiabetic patients. We found that genes associated with ribogenesis, epigenetic regulations, oxidative phosphorylation and cell cycle arrest were upregulated in CD8+ TILs from diabetic patients, while genes associated with PI3K signaling pathway, cytokine response and response to lipids were downregulated. Among the significantly deregulated 1009 genes, 342 (186 upregulated and 156 downregulated) genes were selected based on their link to diabetes, and their associations with the presence of specific CRC pathological parameters were assessed using GDC TCGA colon database. The 186 upregulated genes were associated with the presence of colon polyps history (P = 0.0007) and lymphatic invasion (P = 0.0025). Moreover, CRC patients with high expression of the 186 genes were more likely to have poorer disease-specific survival (DSS) (Mantel-Cox log-rank P = 0.024) than those with low score. Our data provide novel insights into molecular pathways and biological functions, which could be altered in CD8+ TILs from CRC diabetic versus nondiabetic patients, and reveal candidate genes linked to diabetes, which could predict DSS and pathological parameters associated with CRC progression. However, further investigations using larger patient cohorts and functional studies are required to validate these findings.

Differential gene expression of tumor-infiltrating CD33+ myeloid cells in advanced- versus early-stage colorectal cancer.

Colorectal cancer (CRC) has high mortality rates, especially in patients with advanced disease stages, who often do not respond to therapy. The cellular components of the tumor microenvironment are essentially responsible for dictating disease progression and response to therapy. Expansion of different myeloid cell subsets in CRC tumors has been reported previously. However, tumor-infiltrating myeloid cells have both pro- and anti-tumor roles in disease progression. In this study, we performed transcriptomic profiling of cells of myeloid lineage (CD33+) from bulk CRC tumors at varying disease stages. We identified differentially expressed genes and pathways between CRC patients with advanced stage and early stages. We found that pro-angiogenic and hypoxia-related genes were upregulated, while genes related to immune and inflammatory responses were downregulated in CD33+ myeloid cells from patients with advanced stages, implying that immune cell recruitment and activation could be compromised in advanced disease stages. Moreover, we identified a unique "poor prognosis CD33+ gene signature" by aligning top upregulated and downregulated genes in tumor-infiltrating myeloid cells from our analyses with data from The Cancer Genome Atlas. Our results showed that this gene signature is an independent prognostic indicator for disease-specific survival in CRC patients, potentially reflecting its clinical importance.

Primary mediastinal choriocarcinoma presenting as cutaneous metastasis with resistance to chemotherapy: case report and literature review.

Cutaneous metastases of choriocarcinoma are rare. They may indicate poor prognosis and resistance to chemotherapy. In this report, we present a case of a 25-year-old man who presented with central pleuritic chest pain and right upper arm mass for about a week. The patient also had significant weight loss during the last 5 months along with an episode of generalized seizure. Chest computed tomography scan revealed an 8 cm anterior mediastinal mass. A skin punch biopsy from the right upper arm mass revealed a malignant neoplasm with morphology consistent with metastatic choriocarcinoma. Further work-up revealed multiple lung and brain lesions. Ultrasound of the testes revealed no abnormalities. Several chemotherapy regimens were tried; however, there was no response and the disease showed progression. The patient died 6 months after initial presentation.

Differential expression of TIM-3 in circulation and tumor microenvironment of colorectal cancer patients.

T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) is an inhibitory immune checkpoint, which suppresses anti-tumor immune responses. TIM-3 expression on different immune cells in periphery and tumor microenvironment (TME) of colorectal cancer (CRC) patients has not been fully investigated. We found that TIM-3 was mainly expressed on monocytic myeloid cells (MMCs) and antigen-presenting cells (APCs) in circulation but was mainly expressed on T cells and APCs in the TME. Additionally, TIM-3- T cells co-expressed higher levels of PD-1 than TIM-3+ T cells in normal tissue. In contrast, TIM-3+ T cells in the TME showed significantly higher PD-1 expression. Interestingly, there was a trend towards increased levels of TIM-3+ APCs with disease stages; however, levels of TIM-3+ T cells were decreased with disease stages in the TME. This study shows the differential expression of TIM-3 on different immune cells in circulation and TME of CRC patients, and their associations with disease stages.

Expression of immune checkpoints and T cell exhaustion markers in early and advanced stages of colorectal cancer.

Despite recent advances in colorectal cancer (CRC) treatment, a large proportion of patients show limited responses to therapies, especially in advanced stages. There is an urgent need to identify prognostic biomarkers and/or therapeutic targets in advanced stages, aiming to improve the efficacy of current treatments. We aimed to determine prognostic biomarkers in tumor tissue and circulation of CRC patients, with a special focus on T cell exhaustion markers. We found that mRNA levels of PD-1, TIM-3, CTLA-4, TIGIT, CD160, CD244, KLRG1, TOX2, TOX3, Ki-67, and PRDM1 were elevated in CRC tumor tissues. We also investigated differences in gene expression between early and advanced disease stages. We found that TOX and potentially TIM-3, CTLA-4, VISTA, TIGIT, KLRG1, TOX2, SIRT1, Ki-67, and Helios mRNA levels in tumor tissue were elevated in advanced disease stages, suggesting their potential roles in CRC progression. In contrast, PD-1 and CD160 levels in tumor tissue were downregulated in advanced stages. In the circulation of CRC patients, mRNA levels of PD-1, VISTA and LAG-3 were higher than those of healthy individuals. Moreover, in circulation, PD-1, CTLA-4 and TIGIT mRNA levels were reduced in advanced stages. Interestingly, levels of PD-1 in both tumor tissue and circulation were reduced in advanced stages, suggesting that targeting PD-1 in patients with advanced stages could be less effective. Altogether, these findings suggest some potential T cell exhaustion markers that could be utilized as prognostic biomarkers and/or therapeutic targets for CRC. However, further investigations and validations in larger cohorts are required to confirm these findings.

Multifocal Epithelioid Hemangioma of the Penis in a 4-Year-Old Child: A Case Report.

Epithelioid hemangioma (EH) is a rare benign vascular tumor which has wide morphological spectrum. In its typical forms, it is characterized histologically by lobular proliferation of vascular spaces lined by plump endothelial cells with variable inflammatory cell infiltrate in the background. They usually occur in middle-aged women and have predilection for the head and neck site, especially postauricular region. In this study, we report a case of a 4-year-old boy who presented with 2 red-raised skin lesions on the penis. Histopathologic examination revealed a dermal lesion composed of vascular spaces lined by epithelioid endothelial cells. The cells are bland with hobnail protrusions into the lumen. There is no cytological atypia or mitotic activity. The stroma is fibrotic with scant inflammatory cells. By immunoperoxidase stains, the tumor cells are positive with the vascular markers CD31 and CD34 but negative with the epithelial marker cytokeratin AE1/AE3. The diagnosis of multifocal EH was rendered. To the best of our knowledge, this is the first reported case in the English literature of multifocal EH developing in a child's penis.

Urachal mixed adenocarcinoma and small cell neuroendocrine carcinoma with widespread metastasis and resistance to chemotherapy: a case report.

Neuroendocrine carcinoma arising from the urachus is extremely rare. We describe a case of a 33-year-old gentleman who presented with hematuria and diagnosed to have a composite adenocarcinoma and small cell neuroendocrine carcinoma arising from the urachus. The patient also had widespread metastasis at the time of presentation, therefore, he was referred for chemotherapy. However, the disease showed progression despite treatment. Recognition of neuroendocrine carcinoma component in urachal tumors, although rare, is very essential as this histologic type carries poor prognosis with aggressive clinical outcome.

Cirrhosis due to hepatic sarcoidosis: A rare presentation.

Key Clinical Message: Sarcoidosis, although predominantly affecting the lungs, can present with cirrhosis, posing diagnostic challenges. Elevated ACE levels and atypical liver enzyme patterns should prompt consideration of sarcoidosis in cryptogenic cirrhosis cases, necessitating comprehensive evaluation including liver biopsy and imaging for accurate diagnosis and timely management. Abstract: Sarcoidosis is a systemic disease that can affect various organs, leading to a diverse range of clinical manifestations that make diagnosis challenging. Here, we present a case of sarcoidosis in a middle-aged male who presented with cirrhosis. The cause of cirrhosis remained unknown for 4 years until the development of lymphadenopathy and ground-glass opacities on lung imaging. A liver biopsy was performed, which revealed noncaseating granulomatous inflammation, thereby identifying sarcoidosis as the cause of cirrhosis. The patient was treated with oral steroids, which slightly improved his liver function over a short period. Given the diverse presentations of sarcoidosis, it should be considered as a possible differential diagnosis in cases of cryptogenic cirrhosis.

A rare case of myxoma presenting as a scrotal lump.

A myxoma is a benign intramuscular gelatinous tumor that is rarely known to arise from the scrotum. It can be confused both clinically and radiologically with other more common scrotal wall lesions such as a sebaceous cyst or an abscess. We report a case of a 54-year-old patient who presented with a scrotal wall swelling that was initially suspected to be an infected cyst or cold abscess on imaging. The final diagnosis of a myxoma was made after surgical excision and histopathological examination.

Potential pitfalls in reporting non-neoplastic gastrointestinal mucosal biopsies.

Biopsies taken from the gastrointestinal tract (GIT) comprise a significant percentage of the pathologists' routine work. The variable histology and normal components of each organ along the GIT, as well as the different ways of responding to injury among these organs, can cause morphological changes that could result in potential diagnostic pitfalls. Herein, we review the pathological conditions of the GIT that could cause these diagnostic pitfalls. Our aim was to increase awareness among pathologists and trainees regarding these conditions and provide a pragmatic approach to prevent them and achieve a correct diagnosis.

Primary Sarcomas of the Larynx: A Case Series of Four Different Histopathologic Types.

Primary laryngeal sarcomas are rare. Their nomenclature and classification are similar to soft tissue counterparts; however, there are notable differences between clinical presentation, behavior, treatment, and follow-up. There is sparse information regarding the clinical features, biologic behavior, and treatment modalities of laryngeal sarcomas. To increase our understanding about these tumors, we describe herein an additional series of four cases of different pathologic types of laryngeal sarcomas, including low-grade chondrosarcoma, leiomyosarcoma, well-differentiated liposarcoma, and undifferentiated pleomorphic sarcoma. Our main aim is to upsurge awareness about the morphologic variations of laryngeal sarcomas, to avoid potential pitfalls during histopathologic examination. It is essential to ensure that correct diagnosis, subclassification, and grading are achieved for proper guidance of treatment and clinical follow-up at multidisciplinary team meetings.

Cutaneous Sarcoidosis: A Differential Diagnosis to Consider in Undiagnosed Skin Lesions.

The presentation of sarcoidosis varies depending on the organs involved. Cutaneous sarcoidosis usually presents with other organ involvement, but isolated presentation is possible. However, diagnosing isolated cutaneous sarcoidosis can be challenging in resource-poor countries, particularly where sarcoidosis is relatively uncommon, since cutaneous sarcoidosis usually does not cause troublesome symptoms. We present a case of cutaneous sarcoidosis in an elderly female who had been suffering from skin lesions for nine years. The diagnosis was made after the appearance of lung involvement, which raised the suspicion of sarcoidosis and prompted a skin biopsy. The patient was then treated with systemic steroids and methotrexate, and her lesions improved shortly thereafter. This case highlights the importance of considering sarcoidosis as a possible cause of undiagnosed, refractory cutaneous lesions.

Bilateral large cell calcifying Sertoli cell tumours: A testicular preservation approach in a young male.

Testicular Large cell calcifying Sertoli cell tumours (LCCSTs) are extremely rare. The primary challenge in benign LCCSTs, which are typically multifocal and bilateral tumours affecting young males, is to confirm the diagnosis to avoid radical intervention and preserve fertility potential. Patient clinical presentation, laboratory results, diagnostic radiological tests along with confirmatory histopathological studies, are the cornerstones in such cases, nevertheless genetic testing is warranted, as LCCSTs can be part of genetic syndrome such Carney complex. We present a case of bilateral benign LCCSTs in young male managed with testicular preservation approach with characteristic clinical, radiological and histopathological features.

Co-expression of PD-1 with TIGIT or PD-1 with TIM-3 on tumor-infiltrating CD8+ T cells showed synergistic effects on improved disease-free survival in treatment-naïve CRC patients.

Immune checkpoints (ICs) are highly expressed on tumor-infiltrating immune cells (TIICs) in different malignancies, including colorectal cancer (CRC). T cells play crucial roles in shaping CRC, and their presence in the tumor microenvironment (TME) has proven to be one of the best predictors of clinical outcomes. A crucial component of the immune system is cytotoxic CD8+ T cells (CTLs), which play decisive roles in the prognosis of CRC. In this study, we investigated associations of immune checkpoints expressed on tumor-infiltrating CD8+ T cells with disease-free survival (DFS) in 45 naïve-treatment CRC patients. First, we examined the associations of single ICs, and found that CRC patients with higher levels of T-cell immunoglobulin and ITIM-domain (TIGIT), T-cell immunoglobulin and mucin domain-3 (TIM-3) and programmed cell death-1 (PD-1) CD8+ T cells tended to have longer DFS. Interestingly, when PD-1 expression was combined with other ICs, there were more evident and stronger associations between higher levels of PD-1+ with TIGIT+ or PD-1+ with TIM-3+ tumor-infiltrating CD8+ T cells and longer DFS. Our findings for TIGIT were validated in The Cancer Genome Atlas (TCGA) CRC dataset. This study is the first to report on the association of co-expression of PD-1 with TIGIT and PD-1 with TIM-3 in CD8+ T cells and improved DFS in treatment-naïve CRC patients. This work highlights the significance of immune checkpoint expression on tumor-infiltrating CD8+ T cells as critical predictive biomarkers, especially when co-expression of different ICs is considered.

Coinfection of HPVs Is Associated with Advanced Stage in Colorectal Cancer Patients from Qatar.

High-risk human papillomaviruses (HPVs) are considered risk factors in the origin of several human malignancies, such as breast, cervical, head and neck, as well as colorectal cancers. However, there are no data reported on the HPV status in colorectal cancer in the State of Qatar. Therefore, we herein examined the presence of high-risk HPVs (16, 18, 31, 33, 35, 45, 51, 52, and 59), using polymerase chain reaction (PCR) in a cohort of 100 Qatari colorectal cancer patients, and their association with tumor phenotype. We found that high-risk HPV types 16, 18, 31, 35, 45, 51, 52, and 59 were present in 4, 36, 14, 5, 14, 6, 41, and 17% of our samples, respectively. Overall, 69 (69%) of the 100 samples were HPV positive; among these, 34/100 (34%) were positive for single HPV subtypes, while 35/100 (35%) of the samples were positive for two or more HPV subtypes. No significant association was noted between the presence of HPV and tumor grade, stage, or location. However, the presence of coinfection of HPV subtypes strongly correlated with advanced stage (stage 3 and 4) colorectal cancer, indicating that the copresence of more than one HPV subtype can significantly worsen the prognosis of colorectal cancer. The results from this study imply that coinfection with high-risk HPV subtypes is associated with the development of colorectal cancer in the Qatari population.