Signet ring cells in the gastrointestinal tract: not always what it seems.

We describe two cases of pseudo-signet ring cells in gastric biopsies of otherwise asymptomatic adult patients. One male patient was diagnosed during follow-up of a previous intestinal type gastric adenocarcinoma and underwent surgery before recognition of this non-malignant entity. He suffered from a secondary anastomotic stenosis requiring dilatation. A second male patient was spared from surgery thanks to timely recognition by the pathologist and is still declared cancer-free until today. This extremely rare nonmalignant mimicker of cancerous signet ring cells, as seen in diffuse type gastric cancer can potentially mislead the clinician. The absence of any endoscopic abnormality should prompt a revision by an experienced pathologist, digestive oncologist and surgeon to avoid unnecessary interventions and morbidity.

Primary signet ring cell carcinoma of the breast: A case report and literature review.

ABSTRACT: Primary signet ring cell carcinoma (SRCC) of the breast is a rare and aggressive type of breast cancer characterized by increased intracellular mucin production. It has a high risk of metastasis and poor prognosis compared to other breast cancer types. We report a 56-year-old woman with primary SRCC of the breast who first presented with retraction on her left breast. Radiological examination revealed a mass that causes the retraction. The patient underwent left modified radical mastectomy, and pathology results showed a 70% signet ring cell pattern. Chemotherapy consists of an adriamycin-cyclophosphamide regimen administered. in this case, we aim to review the literature on this topic and inform the physicians.

Deciphering signet ring cells in the bone marrow of a child - a rare case report with review of literature.

The metastatic gastric adenocarcinoma that diffusely invades the bone marrow frequently has a short clinical course and an unfavourable prognosis. This case study aimed to elucidate the clinicopathological characteristics and prognosis of gastric cancer patients with diffuse bone marrow metastases. The specific clinicopathologic features associated with diffuse bone metastasis from gastric cancer must be given special attention due to the poor prognosis of this condition. Regular follow-up and a bone marrow examination in high-risk patients can assist in identifying advanced disease early.

Successful administration of cetuximab using dose escalation method: a case report.

INTRODUCTION: Cetuximab, used to treat head and neck squamous cell carcinoma and metastatic colorectal cancer, can cause severe infusion reactions. CASE PRESENTATION: We report an 87-year-old East Asian woman with stage IV ileocecal signet ring cell carcinoma who experienced severe allergic reactions to cetuximab despite pre-treatment. A dose escalation method, involving weekly incremental doses with comprehensive pre-treatment and close monitoring, was employed, successfully reducing allergic reactions and allowing safe administration. CONCLUSION: This approach demonstrates a viable alternative for patients with hypersensitivity to cetuximab, warranting further research for personalized treatment optimization.

Primary signet-ring cell carcinoma of the urinary bladder ‒ A rare bladder tumor.

AIM: Primary Signet Ring Cell Carcinoma (SRCC) of the bladder accounts for only 1%‒4% of all bladder malignancies. To date, few studies have been conducted to investigate the characteristics of SRCC. This study aimed to investigate the clinical features and treatments of SRCC and explore the independent risk factors of survival in SRCC patients. PATIENTS AND METHODS: A retrospective study was conducted on 32 eligible patients. The survival rate was calculated with the Kaplan-Meier method, and the COX proportional hazards model was used to investigate the independent risk factors of prognosis. RESULTS: In the present study, the 1-year and 2-year survival rates of SRCC patients were 53.1% and 9.4%, respectively. The TNM stage, tumor differentiation, and metastasis after treatment were risk factors for the prognosis of SRCC patients (p < 0.05), while surgical treatment, chemotherapy, and positive GATA3 expression were protective for prognosis (p < 0.05). Multivariate analysis showed that GATA3 was an independent protective factor for prognosis (p < 0.05), and T-stage was an independent risk factor (p < 0.05). CONCLUSIONS: Primary SRCC of the bladder is highly malignant and has a poor prognosis. Its clinical and imaging findings are usually non-specific. Early radical cystectomy and postoperative adjuvant systemic chemotherapy are helpful to improve the survival rate. T-stage is an independent risk factor for survival, and positive GATA3 expression is protective for primary SRCC of the bladder.

Endoscopic screening for identification of signet ring cell gastric cancer foci in carriers of germline pathogenic variants in CDH1.

To determine the preoperative detection of signet ring cancer cells (SRC) on upper endoscopy (EGD) in patients with CDH1 pathogenic variant (PV) undergoing gastrectomy. To evaluate the development of advanced diffuse gastric cancer (DGC) in patients choosing surveillance. Guidelines recommend prophylactic total gastrectomy (pTG) in CDH1 PV carriers with family history of DGC between 18 and 40 years. Annual EGD with biopsies according to established protocols is recommended in carriers with no SRC and no family history of DGC, with consideration of pTG. Retrospective analysis of asymptomatic patients with CDH1 PVs with ≥ 1 surveillance EGD. Outcomes included pre-operative EGD detection of SRC, surgical stage, and progression to advanced DGC in those electing surveillance with EGD. 48 patients with CDH1 PVs who had ≥ 1 EGD were included. 24/ 48 (50%) underwent gastrectomy, including pTG in 7 patients. SRCC were detected on gastrectomy specimen in 21/24 (87.5%). SRCs were identified by EGD in 17/21 patients who had SRCC on gastrectomy specimens (sensitivity 81%, 17/21). All cancers were stage pT1a. The remaining 17 patients (50% with a family history of gastric cancer) continue in annual EGD surveillance with a median follow-up of 34.6 months. No SRCC or advanced DGC have been diagnosed. No CDH1 PV carriers without SRCC on random biopsies followed in an endoscopic program developed advanced DGC over a median follow up of 3 years. In the short term, EGD surveillance might be a safe alternative to immediate pTG in experienced hands in referral centers.

Treatment Options for Signet Ring Cell Carcinoma of the Urinary Bladder: A Population-Based Study.

OBJECTIVES: Signet ring cell carcinoma (SRCC) of the urinary bladder is a rare and highly aggressive form of bladder cancer, with no widely agreed-upon treatment strategy. The aim of this study was to identify important factors influencing patient prognosis and to assess how various treatment approaches affect survival outcomes. METHODS: A retrospective study was conducted using data from the Surveillance, Epidemiology, and End Results (SEER) Program, including patients with bladder primary SRCC who were presented between 2000 and 2017. Univariate and multivariate Cox regression models were used to examine the impact of various factors on cancer-specific survival (CSS) and overall survival (OS). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were applied to homogenize both groups. The impact of different treatment regimens on patient CSS and OS was analyzed using the Kaplan-Meier method. RESULTS: A total of 33 cases of non-muscular invasive SRCC and 210 cases of muscular invasive SRCC were included in this study. Multivariate analysis identified race, TNM stage, and surgical method as independent variables influencing both OS and CSS. In non-muscle invasive bladder SRCC patients, radical cystectomy showed no CSS benefit compared to transurethral resection of bladder tumors (P = 0.304). For muscle invasive SRCC, patients who underwent partial cystectomy had better OS and CSS compared to those who underwent radical cystectomy (P = 0.019, P = 0.024). However, after conducting a PSM analysis, the differences between the two surgical outcomes were not statistically significant (P = 0.504, P = 0.335). Lymphadenectomy, chemotherapy, and radiation did not show any benefit to the prognosis of patients. CONCLUSION: This study identified race, TNM stage, and surgical approach as significant independent predictors for SRCC outcomes. Simple radical cystectomy and partial cystectomy proved to be effective treatments for SRCC. The optimal treatment option still needs to be supported by a number of prospective research trials.

Unmasking the silent killer: The hidden aggressiveness of signet-ring cell carcinoma in gallbladder cancer.

The prognostic significance of the signet-ring cell component in gallbladder carcinoma (GBC) has not been systematically evaluated. The aim of this study was to assess the similarities and differences between gallbladder signet-ring cell carcinoma (GBSRCA) and gallbladder adenocarcinoma (GBAC) in terms of clinicopathological features and long-term survival. Using the Surveillance, Epidemiology, and End Results (SEER) database, we analyzed 6,612 patients diagnosed with gallbladder cancer between 2000 and 2021. The cohort included 147 patients with GBSRCA and 6,465 with GBAC. Patients with GBSRCA were significantly younger, with 33.3% being age 60 or younger compared to 23.9% of patients with GBAC (p = 0.009). There was a higher proportion of females in the GBSRCA group (77.6%) compared to the GBAC group (70.1%, p = 0.049). GBSRCA was associated with a more advanced tumor stage (T3-T4: 56.5% vs. 44.4%, P = 0.004), higher rates of lymph node metastasis (43.5% vs. 28.0%, P < 0.001), and poorer differentiation status (poorly to undifferentiated: 80.3% vs. 29.7%, P < 0.001). Survival analysis revealed that patients with GBSRCA had significantly worse overall survival (OS) and cancer-specific survival (CSS) compared to patients with GBAC (p < 0.001). GBSRCA was an independent prognostic factor for OS (P = 0.001) in the entire cohort, while the T stage and N stage were independent prognostic factors for OS and CSS in patients with GBSRCA. Even after propensity score matching, patients with GBSRCA still had a poorer prognosis.

[Gastric-type adenocarcinoma consisting of signet-ring cell carcinoma and adenocarcinoma of the fundic gland type:a case report].

After endoscopic treatment for esophageal cancer, a 65-year-old male underwent surveillance esophagogastroduodenoscopy. A 12-mm discolored flat lesion was noted on the greater curvature of the middle gastric body. Magnifying endoscopy with blue laser imaging demonstrated an irregular papillary surface. Biopsy revealed atypical cells with mucus and irregularly distributed nuclei. The lesion was diagnosed as a gastric-type neoplasm with low atypia. Thereafter, endoscopic submucosal dissection (ESD) was conducted and specimen was sent for biopsy. The ESD specimen suggested a signet-ring cell carcinoma with MUC5AC-positive phenotype and adenocarcinoma of the fundic gland type, with MUC6 positivity and pepsinogen I positivity in the shallow and deeper layers, respectively. Moreover, the cervical region of fundic glands demonstrated a transformation zone of the signet-ring cell carcinoma into an adenocarcinoma of the fundic gland type. Herein, we report this rare case along with a literature review.

Signet ring cells and conditional survival after trimodality therapy for esophageal adenocarcinoma.

BACKGROUND AND METHODS: Although signet ring cell (SRC) histology is associated with resistance to neoadjuvant chemoradiotherapy and worse overall survival (OS) in esophageal adenocarcinoma (EAC), its prognostic relationship among patients who survive the early period following resection is unknown. EAC patients who underwent trimodality therapy at a single institution (2006-2018) were identified. Bayesian multivariable regression (BMR) analyses of OS and additional OS from a 3-year landmark were performed. RESULTS: Of 631 patients, SRCs were present in 16.0% (N = 101). SRC was associated with shorter median OS (45.8 [95% confidence interval: 31.0-96.7] vs. 79.8 [63.0-107.2] months; p = 0.014). In BMR analysis, the absence of an SRC component was moderately associated with improved OS (probability of beneficial effect, PBE = 0.879). Three-year conditional BMR analysis of additional OS (N = 357) showed that SRC status no longer had a prognostic effect (PBE = 0.546); higher pathological stage was strongly associated with worse additional OS (PBE < 0.001). CONCLUSIONS: The presence of SRC portends worse OS following trimodality therapy for EAC. However, this prognostic impact is dynamic and abates by 3 years postoperatively. In contrast, a higher pathological stage is strongly associated with poor overall and 3-year conditional survival. DISCUSSION: These findings may inform postoperative patient counseling and surveillance protocols.

Response of various histological types of locally advanced rectal cancer to neoadjuvant multimodality therapy.

Objectives: To determine the response of various histological types of locally advanced rectal cancer to neoadjuvant multimodality therapy. METHODS: The non-randomised, quasi-experimental retrospective cohort study was conducted at the Combined Military Hospital, Rawalpindi, Pakistan, and comprised data of patients treated between January 1, 2020, to September 30, 2021. The data retrieved related to histologically proven and locally advanced rectal cancer patients aged 18-70 years receiving neoadjuvant chemoradiotherapy. Radiotherapy dose was 45 gray to pelvis with a boost to gross tumour of 5.4 gray in 3 fractions by using volumetric arc therapy concurrently with capecitabine 625mg/m² daily. A magnetic resonance imaging scan of pelvis with contrast was done at 5-10 weeks before surgery. Histological response to neoadjuvant treatment of various histological types was evaluated using the Rectal Cancer Regression Grade. Data was analysed using SPSS 22. RESULTS: Of the 182 patients evaluated, 108(59.34%) were included; 64(59.3%) males and 44(40.7%) females. The overall mean age was 45.4±5.2 years. Regression status was grade 1 in 24(22%) patients, grade 2 in 43(40%) and grade 3 in 41(38%) (p=0.074). There were 12(11.11%) patients with signet ring cell and 10(83.3%) showed pathological tumour regression. There were 17(15.74%) patients with mucinous variant, and 12(70.5%) had tumour regression. There were 79(73.15%) patients with adenocarcinoma, and 59(74.6%) of them showed tumour regression. . CONCLUSIONS: There was less tumour regression in mucinous and signet ring cell variants of adenocarcinoma. Modification and intensification of neoadjuvant therapy may be required in such histologies.

A prognostic framework for predicting lung signet ring cell carcinoma via a machine learning based cox proportional hazard model.

PURPOSE: Signet ring cell carcinoma (SRCC) is a rare type of lung cancer. The conventional survival nomogram used to predict lung cancer performs poorly for SRCC. Therefore, a novel nomogram specifically for studying SRCC is highly required. METHODS: Baseline characteristics of lung signet ring cell carcinoma were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression and random forest analysis were performed on the training group data, respectively. Subsequently, we compared results from these two types of analyses. A nomogram model was developed to predict 1-year, 3-year, and 5-year overall survival (OS) for patients, and receiver operating characteristic (ROC) curves and calibration curves were used to assess the prediction accuracy. Decision curve analysis (DCA) was used to assess the clinical applicability of the proposed model. For treatment modalities, Kaplan-Meier curves were adopted to analyze condition-specific effects. RESULTS: We obtained 731 patients diagnosed with lung signet ring cell carcinoma (LSRCC) in the SEER database and randomized the patients into a training group (551) and a validation group (220) with a ratio of 7:3. Eight factors including age, primary site, T, N, and M.Stage, surgery, chemotherapy, and radiation were included in the nomogram analysis. Results suggested that treatment methods (like surgery, chemotherapy, and radiation) and T-Stage factors had significant prognostic effects. The results of ROC curves, calibration curves, and DCA in the training and validation groups demonstrated that the nomogram we constructed could precisely predict survival and prognosis in LSRCC patients. Through deep verification, we found the constructed model had a high C-index, indicating that the model had a strong predictive power. Further, we found that all surgical interventions had good effects on OS and cancer-specific survival (CSS). The survival curves showed a relatively favorable prognosis for T0 patients overall, regardless of the treatment modality. CONCLUSIONS: Our nomogram is demonstrated to be clinically beneficial for the prognosis of LSRCC patients. The surgical intervention was successful regardless of the tumor stage, and the Cox proportional hazard (CPH) model had better performance than the machine learning model in terms of effectiveness.

Reduced expression of SOX11 in colorectal adenocarcinoma is associated with mucinous and signet ring cell types, poor survival, and lower ALK expression.

BACKGROUND: Mucinous and signet ring cell colorectal carcinoma (m/srCRC) are challenging colorectal adenocarcinoma (CRC) types with poor prognosis. This study aimed to investigate SOX11 and ALK immunohistochemical expression in the m/srCRC group, comparing the results to those of nonmucinous CRC (nmCRC) and studying their association with different clinicopathological CRC features to better understand their significance and role. Besides, the study assesses which marker has a better predictive value for clinical practice. METHODS: Tissue microarrays were prepared from 150 CRC blocks distributed equally between the m/srCRC and nmCRC groups. SOX11 and ALK immunohistochemical expressions were compared between both groups. In addition, their association with CRC clinicopathological data and survival was investigated. The Receiver Operating Characteristic (ROC) Curve analysis examined the predictive ability of SOX11 and ALK IHC expression for CRC mortality. RESULTS: Both SOX11 and ALK expression were significantly reduced in m/srCRC compared to nmCRC. SOX11 is significantly associated with other prognostic clinicopathological factors (tumor size, lymph node status, overall TNM stage, grade, lymphovascular and perineural invasion) and overall survival. SOX11 significantly positively correlates with ALK expression. Using the ROC analysis, SOX11 is superior to ALK in survival prediction. CONCLUSION: SOX11 can be used as a prognostic marker and is a suggested therapeutic target in mucinous and signet ring cell colorectal carcinoma through upregulation modulation.

Metastasis of Rectal Signet Ring Cell Carcinoma to Typical Lipoma: A Rare Presentation of the Tumor-to-Tumor Metastasis Phenomenon.

Rectal signet ring cell carcinoma represents a rare subtype of colorectal adenocarcinoma known for its aggressive biological nature and poor prognosis. Although the co-occurrence of colorectal carcinoma with other tumors has been reported, the uncommon phenomenon of tumor-to-tumor metastasis, first described in 1930, remains rare. The most frequent donor neoplasms are lung or breast carcinomas, whereas cerebral meningiomas have been reported to be the most frequent recipient neoplasms. Here we report a case of a typical lipomatous tumor harboring metastatic signet ring cell rectal carcinoma. It is about a 42-year-old man diagnosed with rectal signet ring cell carcinoma and treated with concurrent radiotherapy and chemotherapy followed by an anterior resection and manual coloanal anastomosis with a temporary ileostomy. During the surgery, an abdominal wall lipoma was discovered and excised. A histopathological examination revealed infiltration of the fibro adipose tissue by a mucinous adenocarcinoma with a contingent of signet ring cells. The patient died 12 months after adjuvant chemotherapy due to peritoneal progression. To the best of our understanding, this represents the initial documented instance of tumor-to-tumor metastasis from rectal signet cell carcinoma to a conventional nonvascular lipoma. Consequently, even if one of these tumors appears clinically and radiologically benign, it is prudent to entertain the prospect of tumor-to-tumor metastasis. Thus, a comprehensive pathologic study of both tumors is highly recommended.

Prostate Adenocarcinoma with Signet-Ring Cells and Features of Mucin: A Clinical Case and Literature Review.

Introduction: Signet-ring cells are typically associated with mucin-secreting epithelium; thus, they are most commonly found in the gastrointestinal tract, but not exclusively. Primary signet-ring cell carcinoma of the prostate is a rare and poorly differentiated, aggressive acinar adenocarcinoma variant with a grim prognosis. Clinical Case: In June of 2023, a 54-year-old Caucasian male presented with a complaint of lower urinary tract obstructive symptoms with occasional macrohematuria, non-specific body aches, and shortness of breath. A prostate specimen obtained in transurethral resection of the prostate was sent for histopathological examination. After a series of extraprostatic diagnostic workups, including fibrogastroduodenoscopy, colonoscopy computed tomography imaging, and immunohistochemical studies, the patient was diagnosed with primary prostatic signet-ring cell adenocarcinoma stage IV. Unfortunately, due to the advanced stage of the disease, PE, and third-degree thrombocytopenia, the patient was not a candidate for chemotherapy and died of cardiopulmonary insufficiency later that week. Discussion: Prostatic signet-ring cell carcinoma accounts for 0.02% of all prostate adenocarcinoma cases. Due to its nature and epidemiology, a diligent extraprostatic investigation has to be carried out. The disease often presents with unremarkable clinical symptoms and variable serum prostate-specific antigen results, which may contribute to its late diagnosis. Inconsistent immunohistochemical findings and an unpredictable response to hormonal treatment together pose both diagnostic and therapeutic challenges that negatively affect the prognosis. Conclusions: This study highlights the importance of a multidisciplinary approach and the need for diagnostic and therapeutic consensus within the research community in search of the primary site of the disease, which may positively influence the prognosis.

Clinicopathological features and cancer transcriptomic profiling of poorly cohesive gastric carcinoma subtypes.

Gastric poorly cohesive carcinoma (PCC) manifests with a diffuse pattern and diverse tumor cell morphologies, often indicating a more unfavorable prognosis. Recent consensus has reclassified PCC based on the proportion of signet-ring cells (SRCs) in tumors for research purposes. The two most distinct subtypes, poorly cohesive carcinoma not otherwise specified (PCC-NOS) and signet-ring cell carcinoma (SRCC), are characterized by less than 10% and more than 90% SRCs, respectively. However, research comparing the clinicopathological and transcriptomic differences between these subtypes remains limited. In this study, we conducted a comparative analysis of clinicopathological features in 55 advanced-stage PCCs, consisting of 43 PCC-NOS and 12 SRCC cases. Subsequently, 12 PCC-NOS and 5 SRCC cases were randomly selected for initial cancer-related gene expression profiling and pathway enrichment analysis using the GeoMx digital spatial profiler, followed by validation in a separate validation group comprising 16 PCC-NOS and 6 SRCC cases. These transcriptomic findings were then correlated with tumor morphology and clinicopathological data. PCC-NOS cases exhibited larger tumor size, a higher prevalence of pathological N3 disease, and a worse 1-year progression-free survival rate compared to SRCC cases. Clustering of PCC-NOS and SRCC was successfully achieved using the GeoMx Cancer Transcriptome Atlas. Among all studied genes, only MMP7 showed differential expression, with its overexpression significantly associated with the PCC-NOS subtype, increased perineural invasion, and earlier disease progression. Pathway analysis revealed significantly enriched pathways in PCC-NOS related to vesicle-mediated transport, adaptive immune systems, oncogenic signaling, and extracellular matrix organization, while SRCC displayed significant enrichment in pathways associated with respiratory electron transport and the cell cycle. In conclusion, this study compares and correlates clinicopathological features and transcriptomic data between PCC-NOS and SRCC at advanced stages, employing the latest consensus classification and a novel platform for analysis.

Right-sided versus left-sided colorectal cancer in elderly patients: a sub-analysis of a large multicenter case-control study in Japan.

PURPOSE: This study investigated the impact of sidedness of colorectal cancer (CRC) in elderly patients on the prognosis. METHODS: In a sub-analysis of a multicenter case-control study of CRC patients who underwent surgery at ≥ 80 years old conducted in Japan between 2003 and 2007, both short- and long-term outcomes were compared between right-sided colon cancers (RCCs) and left-sided colorectal cancers (LCCs). RCCs were defined as those located from the cecum to the transverse colon. RESULTS: Among the 1680 patients who underwent curative surgery, 812 and 868 had RCCs and LCCs, respectively. RCCs were more frequent than LCCs in those who were female, had renal comorbidities, and had a history of abdominal surgery. Regarding tumor characteristics, RCCs were larger, invaded more deeply, and were diagnosed as either mucinous or signet ring-cell carcinoma more frequently than LCCs. Regarding the prognosis, patients with RCCs had a significantly longer cancer-specific survival (CS-S) and cancer-specific relapse-free survival (CS-RFS) than those with LCCs. Furthermore, sidedness was determined to be an independent prognostic factor for CS-S and CS-RFS. CONCLUSION: RCCs, which accounted for half of the cases in patients ≥ 80 years old, showed better long-term outcomes than LCCs.

Contemporary outcomes for resected type 1-3 gastroesophageal junction adenocarcinoma: a single-center experience.

BACKGROUND: Surgical resection remains the mainstay of treatment for tumors of the gastroesophageal junction (GEJ). However, contemporary analyses of the Western experience for GEJ adenocarcinoma are sparsely reported. METHODS: Patients with GEJ adenocarcinoma undergoing resection between 2012 and 2022 at a single institution were grouped based on Siewert subtype and analyzed. Pathologic and treatment related variables were assessed with relation to outcomes. RESULTS: A total of 302 patients underwent resection: 161 (53.3%) with type I, 116 (38.4%) with type II, and 25 (8.3%) with type III tumors. Most patients received neoadjuvant therapy (86.4%); 86% of cases were performed in a minimally invasive fashion. Anastomotic leak occurred in 6.0% and 30-day mortality in only 0.7%. The rate of grade 3+ morbidity was lower for the last 5 years of the study than for the first 5 years (27.5% vs 49.3%, P < .001), as was median length of stay (7 vs 8 days, P < .001). There was a significantly greater number of signet ring type tumors among type III tumors (44.0%) than type I/II tumors (11.2/12.9%, P < .001). Otherwise, there was no difference in the distribution of pathologic features among Siewert subtypes. Notably, there was a significant difference in 3-year overall survival based on Siewert classification: type I 60.0%, type II 77.2%, and type III 86.3% (P = .011). Siewert type I remained independently associated with worse survival on multivariable analysis (hazard ratio, 4.5; P = .023). CONCLUSIONS: In this large, single-institutional series, operative outcomes for patients with resected GEJ adenocarcinoma improved over time. On multivariable analysis, type I tumors were an independent predictor of poor survival.

Effect of chemotherapy on prognosis in patients with primary pancreatic signet ring cell carcinoma: A large real-world study based on machine learning.

BACKGROUND: Primary pancreatic signet ring cell carcinoma (PSRCC), an extremely rare histologic variant of pancreatic cancer, has a poor prognosis. This study aimed to investigate the prognostic value of chemotherapy in PSRCC. METHODS: Patients with PSRCC between 2000 and 2019 were identified using the Surveillance Epidemiology and End Results (SEER) database. The main outcomes in this study were cancer-specific survival (CSS) and overall survival (OS). The baseline characteristics of patients were compared using Pearson's Chi-square test. Kaplan-Meier analysis was used to generate the survival curves. Least absolute shrinkage and selection operator (LASSO), univariate and multivariate Cox regression models, and Random Survival Forest model were used to analyze the prognostic variables for OS and CSS. The variance inflation factors (VIFs) were used to analyze whether there was an overfitting problem. RESULTS: A total of 588 patients were identified. Chemotherapy was an independent prognostic factor for OS and CSS, and significantly associated with OS (HR = 0.33, 95% CI = 0.27-0.40, P <0.001) and CSS (HR = 0.32, 95% CI = 0.26-0.39, P <0.001). CONCLUSIONS: Chemotherapy showed beneficial effects on OS and CSS in patients with PSRCC and should be recommended in clinical practice.