Primary Mucinous Carcinoma of the Thyroid: A Case Report, Literature Review, and Immunohistochemistry Summary.

Introduction: Primary mucinous carcinoma of the thyroid is an exceedingly rare malignancy that is histologically similar to mucinous carcinoma of other sites. Accurate diagnosis is a challenging yet crucial component of clinical management for both patients and our understanding of this rare disease. Case Presentation: We report the case of a 69-year-old male patient with primary mucinous carcinoma of the thyroid. Microscopic examination of a biopsy specimen showed fibrous tissue, which was extensively and irregularly infiltrated by a cytologically malignant epithelial neoplasm showing glandular differentiation with mucin production. Immunohistochemistry demonstrated that tumor cells were positive for TTF1, thyroglobulin, CK7, and PAX8. Co-expression of TTF1 and PAX8 is most commonly seen in thyroid tumors. These findings support our diagnosis of mucinous carcinoma of thyroid origin, which is rare and highly aggressive. Conclusion: In this report, we present the only documented case of primary mucinous carcinoma of the thyroid reported in the United States in the last decade. The diagnosis of primary mucinous carcinoma of the thyroid can be challenging. Therefore, we discuss and detail the clinicopathologic tumor profile and provide more current, detailed histological criteria to assist in the diagnosis of this rare disease.

Case report: Metastatic ovarian mucinous carcinoma to the breast: diagnostic challenges and pitfalls.

Metastases to the breast from extramammary sources are extremely rare, with the ovary, primarily high-grade serous carcinoma, being the most common origin. We report a case of breast metastases from advanced stage ovarian mucinous carcinoma in a 48-year-old female- a case hitherto unreported in the literature. The case is noteworthy for its atypical presentation marked by an areolar rash, clinically suggestive of Paget disease of the nipple. This unique clinical scenario, coupled with histopathological examination revealing in-situ-like carcinoma component, posed a diagnostic challenge in discerning the tumour origin. We emphasize the need for heightened awareness among pathologists to avoid misdiagnosing metastatic carcinomas as primary breast tumours, a potential pitfall with significant clinical implications.

Mucinous Carcinoma of the Breast: A Case Report.

This case report presents the diagnostic journey of a 65-year-old female presenting with symptoms suggestive of breast pathology, ultimately diagnosed with mucinous carcinoma, following comprehensive clinical evaluation and histopathological confirmation. Initial assessments indicated a fibroadenoma; however, subsequent histopathological examination revealed mucinous carcinoma, highlighting the importance of histopathological confirmation in establishing definitive diagnoses. The case underscores the challenges in distinguishing between benign and malignant breast lesions based on clinical presentation and imaging findings alone. The multidisciplinary approach facilitated discussions regarding treatment options tailored to the patient's clinical and pathological characteristics. This case emphasizes the significance of a comprehensive diagnostic approach, integrating clinical evaluation, imaging studies, and histopathological analysis, in ensuring accurate diagnosis and guiding optimal management strategies for patients with breast cancer.

Pure mucinous adenocarcinoma of the breast with the rare lymphoplasmacytic infiltration: A case report with review of literature.

Key Clinical Message: A unique ER/PR-positive mucinous adenocarcinoma of breast but CK7/CK20 negativity. A rare finding of Lymphoplasmacytic Infiltration is noted. Successful treatment included modified radical mastectomy and tamoxifen-based therapy, leads to remission. Abstract: Mucinous carcinoma, which is characterized by the presence of abundant extracellular mucin, is a rare and distinctive subtype of invasive breast cancer. This subtype accounts for less than 5% of all invasive breast cancers, with pure mucinous carcinoma representing only around 2%. It is most commonly found in older patients, typically in the sixth to early eighth decade of life. We present the case of a 55-year-old female with a 15-year history of a painless, gradually enlarging palpable lump on her left breast. Upon examination, a 5 × 5 cm lump with well-defined margins and a hard consistency was found in the lower outer quadrant of the left breast. Histopathological examination confirmed a diagnosis of Mucinous Adenocarcinoma of the Left Breast. The patient underwent modified radical mastectomy and received adjuvant endocrine therapy with tamoxifen due to hormone receptor-positive status. Mucinous carcinoma of the breast is a unique entity with specific histological features including the presence of extracellular mucin pools. Immunohistochemical staining is crucial for determining hormone receptor status, which can guide treatment decisions. Although surgical intervention is the primary approach, the extent of surgery may vary, ranging from lumpectomy to mastectomy. Adjuvant therapies such as chemotherapy and radiotherapy may also be considered based on individual cases. This case underscores the importance of a multidisciplinary approach in managing rare subtypes of breast cancer, such as mucinous carcinoma. Accurate diagnosis, appropriate surgical intervention, adjuvant therapy, and long-term follow-up are critical components of treatment.

Mucin-producing tumors of the ovary--preoperative differentiation between metastatic ovarian mucinous carcinoma and primary mucinous malignant tumors.

OBJECTIVE: To investigate the clinical and magnetic resonance imaging (MRI) features for preoperatively discriminating  primary ovarian mucinous malignant tumors (POMTs) and metastatic mucinous carcinomas involving the ovary (MOMCs). METHODS: This retrospective multicenter study enrolled 61 patients with 22 POMTs and 49 MOMCs, which were pathologically proved between November 2014 to Jane 2023. The clinical and MRI features were evaluated and compared between POMTs and MOMCs. Univariate and multivariate analyses were performed to identify the significant variables between the two groups, which were then incorporated into a predictive nomogram, and ROC curve analysis was subsequently carried out to evaluate diagnostic performance. RESULTS: 35.9% patients with MOMCs were discovered synchronously with the primary carcinomas; 25.6% patients with MOMCs were bilateral, and all of the patients with POMTs were unilateral. The biomarker CEA was significantly different between the two groups (p = 0.002). There were significant differences in the following MRI features: tumor size, configuration, enhanced pattern, the number of cysts, honeycomb sign, stained-glass appearance, ascites, size diversity ratio, signal diversity ratio. The locular size diversity ratio (p = 0.005, OR = 1.31), and signal intensity diversity ratio (p = 0.10, OR = 4.01) were independent predictors for MOMCs. The combination of above independent criteria yielded the largest area under curve of 0.922 with a sensitivity of 82.3% and specificity of 88.9%. CONCLUSIONS: Patients with MOMCs were more commonly bilaterally and having higher levels of CEA, but did not always had a malignant tumor history. For ovarian mucin-producing tumors, the uniform locular sizes and signal intensities were more predict MOMCs.

Differential diagnosis of breast mucinous carcinoma with an oval shape from fibroadenoma based on ultrasonographic features.

BACKGROUND: Approximately 50% of breast mucinous carcinomas (MCs) are oval and have the possibility of being misdiagnosed as fibroadenomas (FAs). We aimed to identify the key features that can help differentiate breast MC with an oval shape from FA on ultrasonography (US). METHODS: Seventy-six MCs from 71 consecutive patients and 50 FAs with an oval shape from 50 consecutive patients were included in our study. All lesions pathologically diagnosed. According to the Breast Imaging Reporting and Data System (BI-RADS), first, the ultrasonographic features of the MCs and FAs were recorded and a final category was assessed. Then, the differences in ultrasonographic characteristics between category 4 A (low-risk group) and category 4B-5 (medium-high- risk group) MCs were identified. Finally, other ultrasonographic features of MC and FA both with an oval shape were compared to determine the key factors for differential diagnosis. The Mann-Whitney test, χ2 test or Fisher's exact test was used to compare data between groups. RESULTS: MCs with an oval shape (81.2%) and a circumscribed margin (25%) on US were more commonly assessed in the low-risk group (BI-RADS 4 A) than in the medium-high-risk group (BI-RADS 4B-5) (20%, p < 0.001 and 0%, p = 0.001, respectively). Compared with those with FA, patients with MC were older, and tended to have masses with non-hypoechoic patterns, not circumscribed margins, and a posterior echo enhancement on US (p < 0.001, p < 0.001, and p = 0.003, respectively). CONCLUSION: The oval shape was the main reason for the underestimation of MCs. On US, an oval mass found in the breast of women of older age with non-hypoechoic patterns, not circumscribed margins, and a posterior echo enhancement was associated with an increased risk of being an MC, and should be subjected to active biopsy.

Ever Expanding Morphologic Patterns of Mesonephric-like Adenocarcinomas of the Uterine Corpus: A Report of Two Tumors and a Brief Review of the Literature.

Mesonephric-like adenocarcinoma (MLA) of the endometrium shows a variety of morphologic appearances, including small glands, tubules with eosinophilic materials in the lumen, prominent papillary patterns, spindled cells, solid formations, and corded and hyalinized patterns. Unique morphology, characteristic immunohistochemical staining patterns, molecular alterations, and awareness of the pathologists make it possible to identify this tumor accurately. This report of two additional morphologic patterns, intestinal goblet cells mimicking intestinal-type mucinous carcinoma and squamous differentiation with spindle and epithelioid cells mimicking carcinosarcoma of the endometrium will expand the literature on MLA.

Primary cutaneous mucinous carcinoma of the scalp masquerading as a benign dermatological mass - A case report.

INTRODUCTION AND IMPORTANCE: Primary cutaneous mucinous carcinoma (PCMC) is a rare low-grade malignant neoplasm derived from the sweat glands. Local recurrence of PCMC occurs frequently, but these lesions rarely metastasize. Due to the absence of classical demographic and clinical characteristics, PCMCs masquerade as sebaceous cyst, lipoma, pilomatrixoma, chalazion, or squamous cell carcinoma. This misdiagnosis frequently leads to incomplete surgical excision which necessitates further surgical therapy for a curative intent. CASE PRESENTATION: We present a case of PCMC in a 45-year-old woman which presented as a slow- growing and symptomless nodule in the scalp. After clinical evaluation, the patient had a typical surgical excision for a benign-looking lesion. Histological evaluation of the specimen confirmed a localized PCMC in the scalp with involved surgical margins. CLINICAL DISCUSSION: A thorough oncological assessment by PET-CT scan and radionuclide scintigraphy was performed. Later, a wide local excision using a gamma probe for intra-operative radionuclide localization of the tumor area and sentinel lymph nodes was done. CONCLUSION: The patient did not have any regional or distant metastases and remained stable at the time of reporting this case.

Whole-tumor histogram analysis of multiparametric breast magnetic resonance imaging to differentiate pure mucinous breast carcinomas from fibroadenomas with high-signal intensity on T2WI.

PURPOSE: To investigate the utility of whole-tumor histogram analysis based on multiparametric MRI in distinguishing pure mucinous breast carcinomas (PMBCs) from fibroadenomas (FAs) with strong high-signal intensity on T2-weighted imaging (T2-SHi). MATERIAL AND METHODS: The study included 20 patients (mean age, 55.80 ± 15.54 years) with single PBMCs and 29 patients (mean age, 42.31 ± 13.91 years) with single FAs exhibiting T2-SHi. A radiologist performed whole-tumor histogram analysis between PBMC and FA groups with T2-SHi using multiparametric MRI, including T2-weighted imaging (T2WI), diffusion weighted imaging (DWI) with apparent diffusion coefficient (ADC) maps, and the first (DCE_T1) and last (DCE_T4) phases of T1-weighted dynamic contrast-enhanced imaging (DCE) images, to extract 11 whole-tumor histogram parameters. Histogram parameters were compared between the two groups to identify significant variables using univariate analyses, and their diagnostic performance was assessed by receiver operating characteristic (ROC) curve analysis and logistic regression analyses. In addition, 15 breast lesions were randomly selected and histogram analysis was repeated by another radiologist to assess the intraclass correlation coefficient for each histogram feature. Pearson's correlation coefficients were used to analyze the correlations between histogram parameters and Ki-67 expression of PMBCs. RESULTS: For T2WI images, mean, median, maximum, 90th percentile, variance, uniformity, and entropy significantly differed in PBMCs and FAs with T2-SHi (all P < 0.05), yielding a combined area under the curve (AUC) of 0.927. For ADC maps, entropy was significantly lower in FAs with T2-SHi than in PMBCs (P = 0.03). In both DCE_T1 and DCE_T4 sequences, FAs with T2-SHi showed significantly higher minimum values than PBMCs (P = 0.007 and 0.02, respectively). The highest AUC value of 0.956 (sensitivity, 0.862; specificity, 0.944; positive predictive value, 0.962; negative predictive value, 0.810) was obtained when all significant histogram parameters were combined. CONCLUSIONS: Whole-tumor histogram analysis using multiparametric MRI is valuable for differentiating PBMCs from FAs with T2-SHi.

Establishment and characterization of NCC-PMP2-C1: a novel patient-derived cell line of pseudomyxoma peritonei with signet ring cells.

Pseudomyxoma peritonei (PMP) is a rare phenomenon, characterized by accumulation of mucus in the abdominal cavity due to a mucinous neoplasm. Histologically, PMP is divided into three prognostic classes, namely low-grade mucinous carcinoma peritonei (LGMCP), high-grade mucinous carcinoma peritonei (HGMCP), and high-grade mucinous carcinoma peritonei with signet ring cells (HGMCP-S); HGMCP-S exhibits the worst prognosis. Complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy have been established as the standard therapy for PMP. However, 50% of patients with PMP experience a recurrence, and 30-40% are unable to receive the standard treatment due to invasive diseases. Therefore, novel therapies are required for their treatment. Although patient-derived cell lines are important tools for basic and pre-clinical research, PMP cell lines derived from patients with HGMCP-S have never been reported. Thus, we established a novel PMP cell line NCC-PMP2-C1, using surgically resected tumor tissue from a patient with HGMCP-S. NCC-PMP2-C1 cells were maintained for more than five months and passaged 30 times under culture conditions. NCC-PMP2-C1 cells exhibited multiple deletions and somatic mutations, slow growth, histological features, and dissemination of tumor cells in nude mice. Screening for the anti-proliferative effects of anti-cancer drugs on cells revealed that bortezomib, mubritinib, and romidepsin had a significant response against NCC-PMP2-C1 cells. Thus, the NCC-PMP2-C1 cell line is the first PMP cell line harboring signet ring cells and will be a valuable resource for basic and preclinical studies of HGMCP-S.

Fertility-Sparing Surgery in Infiltrative Mucinous Carcinoma of the Ovary.

Introduction: Mucinous ovarian carcinoma is often diagnosed early and can affect young patients. The preservation of the female reproductive organ is one of the critical issues, especially for nulliparous women. This case report aims to reconsider the safe outcome of fertility-sparing surgery for infiltrative type mucinous ovarian carcinoma. Case Presentation: A 28-year-old woman with a right mucinous ovarian carcinoma, infiltrative subtype stage IA was treated by right salpingo-oophorectomy, omentectomy, and lymph nodes staging. A 5-year follow-up showed no signs of relapse, and she completed two full-term natural pregnancies. Conclusion: Conservative surgery is a crucial matter for this patient category. The infiltrative type has a poorer prognosis, but few papers have reported the outcome and the safety of fertility-sparing surgery in this context.

Intestinal­type mucinous carcinoma of the endometrium showing a polypoidal exophytic form: A case report.

Although endometrial cancer is a common malignancy in women, rare histological subtypes can pose diagnostic challenges. Primary endometrial intestinal-type mucinous carcinoma is a newly recognized subtype of endometrial cancer that differs from Müllerian-type endometrial mucinous carcinoma. The present case report documents a rare case of intestinal-type mucinous carcinoma of the endometrium showing a polypoidal exophytic form. The patient, an 80-year-old female, was incidentally diagnosed with a uterine tumor during a follow-up for vulvar Paget's disease. Clinical and imaging examinations revealed a localized mass within the uterine cavity. Hysteroscopy and subsequent histological examination confirmed the presence of intestinal-type mucinous carcinoma of the endometrium. Microscopically, the tumor displayed adenocarcinoma containing an intestinal-type glandular epithelium with mild nuclear atypia. It stained positive for the gastrointestinal markers mucin 2 and caudal type homeobox 2, and stained negatively for estrogen receptor α. The patient underwent surgery and adjuvant chemotherapy, with no evidence of recurrence at the latest follow-up 6 months after surgery. Endometrial intestinal-type mucinous carcinoma is a rare histological subtype of endometrial cancer. Differential diagnoses include Müllerian-type endometrial mucinous carcinoma, endocervical adenocarcinoma, metastasis from gastrointestinal tract adenocarcinoma and non-neoplastic gastric/intestinal metaplasia. However, the prognosis of endometrial intestinal-type mucinous carcinoma remains unclear due to limited reported cases. Existing evidence suggests a poorer prognosis compared with classical mucinous carcinomas of the endometrium. The present case, which is characterized by a polypoidal exophytic tumor without myometrial invasion, showed a favorable outcome. Further documentation and characterization of the aforementioned rare malignancy are necessary to enhance the understanding of its clinical physiology and outcomes. The present case report highlights the diagnostic challenges associated with intestinal-type mucinous endometrial carcinoma. The inclusion of this type of malignancy in the latest World Health Organization classification emphasizes the need for further comprehensive studies and case reports to expand the current knowledge on this rare histological subtype.

Endocrine Mucin-Producing Sweat Gland Carcinoma: Case Presentation with a Comprehensive Review of the Literature.

(1) Background: Endocrine Mucin-Producing Sweat Gland Carcinoma (EMPSGC) is a rare, low-grade, neuroendocrine-differentiated, cutaneous adnexal tumor, officially recognized by the World Health Organization (WHO) Skin Tumors Classification in 2018 as a separate entity and homologue of endocrine ductal carcinoma in situ (eDCIS)/solid papillary carcinoma of the breast. Although it is more frequent in the female sex, between 60 and 70 years old, in the peri-orbital region, EMPSGC has also been described in the male sex, in subjects under 60 and over 80, and in extra-eyelid localizations (cheek, temple, scalp), but also in extra-facial localizations (chest and scrotum). (2) Methods: We present the clinical case of a 71-year-old woman with an undated lesion of the scalp, which presented as a nodule, skin-colored, and 2.5 cm in maximum diameter. We also conduct a comprehensive literature review from 1997 to the end of 2022, consulting PubMed, Scopus, Web of Science (WoS), and Google Scholar using the following keywords: "Endocrine mucin-producing sweat gland carcinoma" and/or "EMPSGC" and/or "skin" and "cutaneous neoplasms". In addition, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 253 patients were recorded; 146 were females (57.7%) and 107 were males (42.2%). The vast majority of the lesions were in the eyelids (peri-ocular region), and only a minority of cases involved the cheeks, supra-auricular, retro-auricular, and occipital region, with very rare cases in the scalp, to which the present is also added. (4) Conclusions: The morphological and immunophenotypical features are essential both for the correct diagnosis and to be able to classify this lesion among the corresponding eDCIS/solid papillary carcinoma of the breast, with neuroendocrine differentiation. Recent papers have attempted to shed light on the molecular features of EMPSGC, and much remains to be conducted in the attempt to subtype the molecular profiles of these entities. Future studies with large case series, and especially with molecular biology techniques, will be needed to further add information about EMPSGC and its relationship in the PCMC spectrum.

Primary mucinous carcinoma of the skin.

Key Clinical Message: Mucinous carcinoma of the skin is clinically characterized by good mobility, slow growth, a macroscopically smooth surface, no easy contact bleeding, and no internal flow on color Doppler; it is thus difficult to distinguish from benign tumors. Abstract: A 58-year-old man presented to our clinic complaining of a right cheek induration, growing over the previous 6 months. The tumor surface was smooth, pink, did not bleed easily, and approximately 10 mm in size with good mobility. Ultrasonography revealed a well-circumscribed hypoechoic homogenous tumor with posterior acoustic enhancement; color Doppler displayed no internal flow. Preoperative diagnosis was intradermal type nevus or dermatofibroma. An excisional biopsy was performed under local anesthesia. The biopsy specimen unexpectedly showed tumor cells with an epithelial alveolar configuration floating in a mucin lake. The tumor cells contained enlarged nuclei and formed atypical columnar epithelium, arranged in fused, honeycomb-like glandular ducts, indicating mucinous carcinoma.

Mucinous carcinoma of the breast: Rare histological entity to know: About two cases and review of literature.

INTRODUCTION AND IMPORTANCE: Breast cancer is the first gynecological cancer in women, dominated by invasive ductal cancer . It is characterized by the presence of extracellular mucus, mucinous carcinoma represents one to 7 % of all invasive carcinomas and by a more favorable prognosis, Presentation of the case: We present two patients followed for an invasive mucinous carcinoma, CLINICAL DISCUSSION: Mucinous carcinoma of the breast is a rare entity. Therapeutic management does not differ from other histological types. It is based on surgery, chemotherapy and radiotherapy. Conservative treatment is recommended for T1, T2. Partial and accelerated irradiation of the breast is currently the most recommended after breast-conserving surgery. CONCLUSION: Mucinous carcinoma is a rare histological entity with a favorable prognosis compared to other histological types. A benign-looking mass on imaging is not always reassuring, especially if it occurs in a woman over 60 years old. Since it can reveal colloid carcinoma.

Synchronous bilateral breast cancer: A first case with lobular and mucinous carcinoma.

This report describes a rare case of synchronous bilateral carcinoma of the breast in a postmenopausal female patient, with mucinous carcinoma measuring 5 cm in the left breast and multifocal multicentric lobular carcinoma in the right breast. The patient underwent a bilateral mastectomy with adjuvant chemotherapy. To the best of our knowledge, this is the first report of a case of mucinous carcinoma and infiltrating lobular carcinoma coexisting in distinct breasts.

A retrospective review of Mohs micrographic surgery trends over more than 10 years in Saudi Arabia.

OBJECTIVES: To review Mohs micrographic surgery (MMS) trends in Saudi Arabia.Mohs micrographic surgery is a precise surgical technique that has been proven to have the highest cure rate with maximum normal tissue preservation. It is the treatment of choice for non-melanoma skin cancer (NMSC), especially the aggressive histopathological forms, and tumors located in high-risk regions or where tissue preservation is a mandate. METHODS: A multicentric retrospective study was performed on patients who underwent MMS between January 2010 and September 2022. The information was extracted from the database of King Saud University Medical City and Prince Sultan Military Medical City in Saudi Arabia. RESULTS: A total of 70 participants were enrolled in this study. Two-thirds (67%) of the tumors that were treated using MMS were basal-cell carcinomas (BCC), 18.6% were squamous cell carcinomas (SCC), 5.7% were sebaceous carcinoma, 4.3% were dermatofibrosarcoma protuberans (DFSP), and 1.4% were rare tumors such as primary mucinous carcinoma. The most common type of reconstruction used to repair post-MMS defect was primary closure in more than half of the patients followed by secondary intention healing (20%). There were no side effects apart from a hematoma in one patient and wound infection in two patients. CONCLUSION: Although MMS is still generally underutilized in Saudi Arabia, its use has increased in the last decade.

On Ultrasonographic Features of Mucinous Carcinoma with Micropapillary Pattern.

Objective: To describe the sonographic features of pure mucinous carcinoma with micropapillary pattern (MUMPC) and compare with different pathological type of mucinous breast carcinoma. Methods: Subjects were retrospectively reviewed at Suzhou Municipal Hospital from January 2015 to June 2019. Sonographic features of 49 cases (9 MUMPC, 19cPMBC, and 21 MMBC) pathologically confirmed MBC were recorded according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon. The differences in sonographic features among different type of mucinous breast carcinoma were discussed, including clinical features and sonographic features, shape, lesion boundary, peripheral hyperechoic ring, echo pattern, posterior acoustic feature, thickness peripheral hyperechoic area, and blood flow. Results: All MUMPC had no lymph node metastasis (88.9%, 8/9), and most of the MUMPC showed no thickness peripheral hyperechoic area (88.9%, 8/9) and blood flow (55.6%, 5/9) within the tumor. Furthermore, MUMPC had mixed cystic and solid components (33.3%, 3/9) and solid echoic (66.7%, 6/9) structures, with regular shape (66.7%, 6/9) and peripheral hyperechoic ring (66.7%, 6/9). Seven cases of the MUMPC showed circumscribed margin (77.8%, 7/9), and there was significant difference among the three groups (p < 0.05). In addition, there were 7 cases (77.8%, 7/9) of MUMPC tumor ≤2cm, which was significantly different from cPMBC (26.3%, 5/19) and MMBC (28.6%, 6/21) (p < 0.05). There was no significant difference in ultrasonographic features of MBC with different sizes when stratified by tumor size (p > 0.05). Conclusion: Most of the MUMPC showed a circumscribed margin, peripheral hyperechoic ring, and without lymph node metastasis and thickness peripheral hyperechoic area. However, it is challenging to distinguish MUMPC from PMBC and MMBC on ultrasound. Future research should focus on developing novel analysis methods for ultrasound imaging, conducting studies with larger sample sizes and diverse population groups.

An integrated radiomics nomogram based on conventional ultrasound improves discriminability between fibroadenoma and pure mucinous carcinoma in breast.

Objective: To evaluate the ability of integrated radiomics nomogram based on ultrasound images to distinguish between breast fibroadenoma (FA) and pure mucinous carcinoma (P-MC). Methods: One hundred seventy patients with FA or P-MC (120 in the training set and 50 in the test set) with definite pathological confirmation were retrospectively enrolled. Four hundred sixty-four radiomics features were extracted from conventional ultrasound (CUS) images, and radiomics score (Radscore) was constructed using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm. Different models were developed by a support vector machine (SVM), and the diagnostic performance of the different models was assessed and validated. A comparison of the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) was performed to evaluate the incremental value of the different models. Results: Finally, 11 radiomics features were selected, and then Radscore was developed based on them, which was higher in P-MC in both cohorts. In the test group, the clinic + CUS + radiomics (Clin + CUS + Radscore) model achieved a significantly higher area under the curve (AUC) value (AUC = 0.86, 95% CI, 0.733-0.942) when compared with the clinic + radiomics (Clin + Radscore) (AUC = 0.76, 95% CI, 0.618-0.869, P > 0.05), clinic + CUS (Clin + CUS) (AUC = 0.76, 95% CI, 0.618-0.869, P< 0.05), Clin (AUC = 0.74, 95% CI, 0.600-0.854, P< 0.05), and Radscore (AUC = 0.64, 95% CI, 0.492-0.771, P< 0.05) models, respectively. The calibration curve and DCA also suggested excellent clinical value of the combined nomogram. Conclusion: The combined Clin + CUS + Radscore model may help improve the differentiation of FA from P-MC.