Objective:To investigate the clinical and pathological characteristics, treatment and prognosis of endometriosis (EM)-associated ovarian mesonephric-like adenocarcinoma (MLA).Methods:Clinical and pathological data were collected from nine patients diagnosed with EM-associated ovarian MLA at the Obstetrics and Gynecology Hospital of Fudan University between January 2022 and December 2024. Histological slides were re-reviewed, immunohistochemical examination and molecular testing were performed, and patient follow-up was conducted.Results:(1) Clinical characteristics: the median age of the nine patients was 54 years (range: 38-69 years). All patients presented with a pelvic mass; five cases also reported abdominal pain. Tumor location included five cases in the right ovary, two in the left ovary, and two involving both ovaries. International Federation of Gynecology and Obstetrics (FIGO) staging showed 3 cases at stage Ⅰ, 4 at stage Ⅱ, and 2 at stage Ⅲ. (2) Pathological features: gross examination revealed mixed solid-cystic masses with solid areas appearing gray-white or yellow-brown; the median maximum tumor diameter was 9.0 cm (range: 2.6-13.0 cm). Microscopically, tumors exhibited various architectural patterns, including tubular, glandular, papillary, slit-like, sex cord-like, glomeruloid, and solid structures, with tubular and glandular patterns being most common. Tumor cells demonstrated mild to moderate nuclear atypia. Of the 11 tumor foci in the 9 cases, 8 showed coexistence of MLA with other tumor components, such as endometrioid carcinoma, borderline endometrioid or borderline seromucinous tumors. In 1 case of MLA mixed with a borderline endometrioid tumor, both components exhibited squamous metaplasia. Immunohistochemistry showed variable expression of GATA-binding protein 3, thyroid transcription factor-1, CD 10, and calretinin, with positive rates of 9/11, 8/11, 5/11, and 3/6, respectively. Two tumor foci (2/11) exhibited focal expression of estrogen receptor and progesterone receptor. All cases displayed wild-type p53 expression. Molecular testing via next-generation sequencing in five patients revealed pathogenic mutations in the KRAS gene (5/5), with 3 cases (3/5) harboring additional pathogenic mutations in other genes. (3) Treatment and prognosis: all patients underwent surgery, supplemented by chemotherapy and (or) targeted therapy. Five patients underwent comprehensive staging surgery, four received cytoreductive surgery, and one patient received targeted therapy. The median follow-up duration was 7 months (range: 2-27 months). Three patients (3/9) experienced recurrence, and no deaths were reported during the follow-up period. Conclusions:EM-associated ovarian MLA demonstrates diverse morphological patterns and frequently coexists with other tumor types. Accurate diagnosis relies on an integrated evaluation of histomorphology, immunohistochemistry, and molecular testing. The primary treatment for EM-associated ovarian MLA is surgery, followed by adjuvant chemotherapy. Patients harboring pathogenic KRAS p.G12C mutations may benefit from targeted therapies. Ovarian MLA is an aggressive tumor, prone to recurrence in the short term, and has a poor prognosis.

Objective:To investigate the correlation of epithelial lesions among different biopsy sites in the female lower genital tract and the relationship between age and lesion distribution.Methods:A total of 406 148 patients with cervical biopsy specimens archived at the Department of Pathology, Obstetrics and Gynecology Hospital of Fudan University from January 2010 to December 2021 were analyzed. Among them, 70 309 cases (17.31%) had concurrent vaginal biopsies, and 16 073 cases (3.96%) had concurrent vulvar biopsies. (1) Cases were divided into four 3-year intervals to compare vaginal or vulvar biopsy rates and high-grade squamous intraepithelial lesion (HSIL) or worse (HSIL +) detection rates across time periods. (2) Correlations between cervical lesions and vaginal or vulvar lesions were assessed. (3) Patients were stratified into three age groups (<30, 30-49, and ≥50 years) to compare vaginal or vulvar HSIL + detection rates. Results:Mean ages of patients with cervical, vaginal, and vulvar biopsies were (41.3±11.0), (47.4±12.5), and (41.9±13.2) years, respectively. Patients with vaginal biopsy were significantly older than cervical or vulvar groups (all P<0.001). (1) Vaginal biopsy rates increased markedly from 7.37% (2010—2012) to 22.76% (2019—2021; χ2=9 205.01, P<0.001); vulvar biopsy rates increased slightly from 2.80% to 5.69% ( χ2=1 777.25, P<0.001). Correspondingly, vaginal HSIL + detection rates rose from 0.28% to >0.5% (0.56% in 2013—2015, 0.59% in 2016—2018, 0.51% in 2019—2021; χ2=134.70, P<0.001), while vulvar HSIL + rates increased from 0.03% to 0.33% ( χ2=56.54, P<0.001). (2) Weak correlation existed between cervical and vaginal lesions ( r=0.28; P<0.001; n=70 309), while cervical-vulvar correlation was weaker ( r=0.22, P<0.001; n=16 073). (3) Vaginal HSIL + detection rates were higher in cervical HSIL + patients aged 30-49 years (26.65%) and ≥50 years (26.79%) versus <30 years (14.63%; both P<0.001). Conversely, vulvar HSIL + detection rates were higher in the <30 years group (23.08%) versus 30-49 years (13.83%) and ≥50 years (12.89%; both P<0.05). Conclusions:Vaginal or vulvar lesion detection rates increase with biopsy frequency. Vaginal lesions correlate with cervical abnormalities, whereas vulvar lesions are relatively independent. In cervical HSIL + patients, those <30 years are more prone to have vulvar HSIL +, while those ≥30 years show higher vaginal HSIL + incidence. These age-specific distribution patterns inform optimized biopsy strategies.

Objective:To investigate the clinicopathological characteristics, diagnosis, origin, and prognosis of primary ovarian mesonephric-like adenocarcinoma.Methods:A total of 17 cases of primary ovarian mesonephric-like adenocarcinoma diagnosed at the Obstetrics and Gynecology Hospital of Fudan University and Jiaxing Maternal and Child Health Care Hospital between January 2018 and September 2024 were included in this study. Histopathological sections were retrospectively reviewed, and clinicopathological data were systematically analyzed. Immunohistochemical analysis, molecular profiling, and clinical follow-up were performed to further characterize the cases.Results:The patients′ age was (57.1±9.3) years. Tumor involvement included 1 bilateral case, 9 left-sided cases, and 7 right-sided cases. Nine cases originated from endometrioid cysts, and 8 cases exhibited coexisting tumor components of other types. Gross examination revealed gray-yellow solid masses or solid components within cysts. Microscopically, the tumors displayed diverse architectural patterns, including papillary, glandular, cystic, tubular, and solid structures, with eosinophilic secretions within glandular lumens and mild to moderate nuclear atypia. Immunohistochemically, the tumors showed variable expression of TTF1, GATA3, CD10, and Calretinin. ER and PR were focally positive in only 2 cases, while others were negative. All cases demonstrated intact DNA mismatch repair proteins expression and wild-type p53 staining patterns. Molecular analysis performed in 10 cases identified pathogenic KRAS mutations in all tested samples. During a follow-up period of 1 to 75 months, 5 cases had recurrence, 1 patient remained alive with disease, and no disease-related death was reported.Conclusions:Ovarian mesonephric-like adenocarcinoma is an aggressive malignancy with a high potential for early recurrence and metastasis. Its frequent association with endometriosis and coexistence with other Müllerian tumors suggest a potential Müllerian origin. The tumor′s diverse morphological spectrum and common admixture with other tumor types often pose diagnostic challenges, making it difficult to distinguish from other gynecological malignancies. Therefore, accurate diagnosis of ovarian mesonephric-like adenocarcinoma is crucial for appropriate clinical management and prognostication.

Objective:To investigate the clinicopathological characteristics, immunophenotype and differential diagnosis of atypical forms of microglandular hyperplasia of the cervix (AMGH).Methods:A total of 29 cases of AMGH diagnosed at the Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China from January 2010 to December 2024 were analyzed. Relevant clinical and pathological data of the patients were collected using the electronic medical record system and medical records copied from the outside hospitals. The patients were followed up.Results:Among the 29 cases, 28 were consultation cases, 22 (79%) of the 28 cases were considered as glandular neoplastic lesions by the original institutions. The nature of the lesion was uncertain in 1 case, the diagnosis was suspicious for AMGH in another 1 case, and only 4 cases were clearly diagnosed as AMGH. The median age of the 29 patients was 44 (43, 48) years. Eighteen (62%) of the 29 cases presented as cervical polyp. Twelve of the 16 tested cases were negative for human papillomavirus. The pathological presentation was complex and diverse, including solid, trabecular, cribriform, and papillary patterns, forming pseudo-invasive structures. The glandular epithelium and proliferating reserve cells had diverse morphologies, which presented with abundant eosinophilic cytoplasm or clear cytoplasm. Signet-ring or hobnail cells were also seen. The nuclear atypia was mild, with 0-7 mitotic figures per 10 HPF. Immature squamous metaplasia was noted. The stroma showed edema, myxoid change and hyaline degeneration, accompanied by infiltration of acute and chronic inflammatory cells. Immunohistochemistry demonstrated that p16 was negative in 8/16 of the cases or patchy positive in the other 8/16, Ki-67 positive rate was less than 10% in all 16 cases, p53 was wild phenotype (9/9), and carcinoembryonic antigen was negative in 4/5 cases and focally positive in 1/5 cases, while p63 was positive in 6/9 of the tested cases.Conclusions:AMGH is a benign non-neoplastic lesion of the cervical glands. Half of the cases occur in perimenopausal or postmenopausal women, often presenting as polypoid hyperplasia or localized cervical thickening/elevation with a friable, fragile texture. Microscopically, it may show a pseudoinvasive pattern, making it prone to misdiagnosis as a malignant lesion. Thus, differentiation from cervical adenocarcinoma, clear cell carcinoma and microglandular endometrioid carcinoma is required. Integration of clinical history, immunohistochemistry and molecular testing may aid in the differential diagnosis.

Objective:To investigate the clinical and pathological characteristics, treatment and prognosis of endometriosis (EM)-associated ovarian mesonephric-like adenocarcinoma (MLA).Methods:Clinical and pathological data were collected from nine patients diagnosed with EM-associated ovarian MLA at the Obstetrics and Gynecology Hospital of Fudan University between January 2022 and December 2024. Histological slides were re-reviewed, immunohistochemical examination and molecular testing were performed, and patient follow-up was conducted.Results:(1) Clinical characteristics: the median age of the nine patients was 54 years (range: 38-69 years). All patients presented with a pelvic mass; five cases also reported abdominal pain. Tumor location included five cases in the right ovary, two in the left ovary, and two involving both ovaries. International Federation of Gynecology and Obstetrics (FIGO) staging showed 3 cases at stage Ⅰ, 4 at stage Ⅱ, and 2 at stage Ⅲ. (2) Pathological features: gross examination revealed mixed solid-cystic masses with solid areas appearing gray-white or yellow-brown; the median maximum tumor diameter was 9.0 cm (range: 2.6-13.0 cm). Microscopically, tumors exhibited various architectural patterns, including tubular, glandular, papillary, slit-like, sex cord-like, glomeruloid, and solid structures, with tubular and glandular patterns being most common. Tumor cells demonstrated mild to moderate nuclear atypia. Of the 11 tumor foci in the 9 cases, 8 showed coexistence of MLA with other tumor components, such as endometrioid carcinoma, borderline endometrioid or borderline seromucinous tumors. In 1 case of MLA mixed with a borderline endometrioid tumor, both components exhibited squamous metaplasia. Immunohistochemistry showed variable expression of GATA-binding protein 3, thyroid transcription factor-1, CD 10, and calretinin, with positive rates of 9/11, 8/11, 5/11, and 3/6, respectively. Two tumor foci (2/11) exhibited focal expression of estrogen receptor and progesterone receptor. All cases displayed wild-type p53 expression. Molecular testing via next-generation sequencing in five patients revealed pathogenic mutations in the KRAS gene (5/5), with 3 cases (3/5) harboring additional pathogenic mutations in other genes. (3) Treatment and prognosis: all patients underwent surgery, supplemented by chemotherapy and (or) targeted therapy. Five patients underwent comprehensive staging surgery, four received cytoreductive surgery, and one patient received targeted therapy. The median follow-up duration was 7 months (range: 2-27 months). Three patients (3/9) experienced recurrence, and no deaths were reported during the follow-up period. Conclusions:EM-associated ovarian MLA demonstrates diverse morphological patterns and frequently coexists with other tumor types. Accurate diagnosis relies on an integrated evaluation of histomorphology, immunohistochemistry, and molecular testing. The primary treatment for EM-associated ovarian MLA is surgery, followed by adjuvant chemotherapy. Patients harboring pathogenic KRAS p.G12C mutations may benefit from targeted therapies. Ovarian MLA is an aggressive tumor, prone to recurrence in the short term, and has a poor prognosis.

Objective:To investigate the correlation of epithelial lesions among different biopsy sites in the female lower genital tract and the relationship between age and lesion distribution.Methods:A total of 406 148 patients with cervical biopsy specimens archived at the Department of Pathology, Obstetrics and Gynecology Hospital of Fudan University from January 2010 to December 2021 were analyzed. Among them, 70 309 cases (17.31%) had concurrent vaginal biopsies, and 16 073 cases (3.96%) had concurrent vulvar biopsies. (1) Cases were divided into four 3-year intervals to compare vaginal or vulvar biopsy rates and high-grade squamous intraepithelial lesion (HSIL) or worse (HSIL +) detection rates across time periods. (2) Correlations between cervical lesions and vaginal or vulvar lesions were assessed. (3) Patients were stratified into three age groups (<30, 30-49, and ≥50 years) to compare vaginal or vulvar HSIL + detection rates. Results:Mean ages of patients with cervical, vaginal, and vulvar biopsies were (41.3±11.0), (47.4±12.5), and (41.9±13.2) years, respectively. Patients with vaginal biopsy were significantly older than cervical or vulvar groups (all P<0.001). (1) Vaginal biopsy rates increased markedly from 7.37% (2010—2012) to 22.76% (2019—2021; χ2=9 205.01, P<0.001); vulvar biopsy rates increased slightly from 2.80% to 5.69% ( χ2=1 777.25, P<0.001). Correspondingly, vaginal HSIL + detection rates rose from 0.28% to >0.5% (0.56% in 2013—2015, 0.59% in 2016—2018, 0.51% in 2019—2021; χ2=134.70, P<0.001), while vulvar HSIL + rates increased from 0.03% to 0.33% ( χ2=56.54, P<0.001). (2) Weak correlation existed between cervical and vaginal lesions ( r=0.28; P<0.001; n=70 309), while cervical-vulvar correlation was weaker ( r=0.22, P<0.001; n=16 073). (3) Vaginal HSIL + detection rates were higher in cervical HSIL + patients aged 30-49 years (26.65%) and ≥50 years (26.79%) versus <30 years (14.63%; both P<0.001). Conversely, vulvar HSIL + detection rates were higher in the <30 years group (23.08%) versus 30-49 years (13.83%) and ≥50 years (12.89%; both P<0.05). Conclusions:Vaginal or vulvar lesion detection rates increase with biopsy frequency. Vaginal lesions correlate with cervical abnormalities, whereas vulvar lesions are relatively independent. In cervical HSIL + patients, those <30 years are more prone to have vulvar HSIL +, while those ≥30 years show higher vaginal HSIL + incidence. These age-specific distribution patterns inform optimized biopsy strategies.

Objective:To investigate the clinicopathological characteristics, diagnosis, origin, and prognosis of primary ovarian mesonephric-like adenocarcinoma.Methods:A total of 17 cases of primary ovarian mesonephric-like adenocarcinoma diagnosed at the Obstetrics and Gynecology Hospital of Fudan University and Jiaxing Maternal and Child Health Care Hospital between January 2018 and September 2024 were included in this study. Histopathological sections were retrospectively reviewed, and clinicopathological data were systematically analyzed. Immunohistochemical analysis, molecular profiling, and clinical follow-up were performed to further characterize the cases.Results:The patients′ age was (57.1±9.3) years. Tumor involvement included 1 bilateral case, 9 left-sided cases, and 7 right-sided cases. Nine cases originated from endometrioid cysts, and 8 cases exhibited coexisting tumor components of other types. Gross examination revealed gray-yellow solid masses or solid components within cysts. Microscopically, the tumors displayed diverse architectural patterns, including papillary, glandular, cystic, tubular, and solid structures, with eosinophilic secretions within glandular lumens and mild to moderate nuclear atypia. Immunohistochemically, the tumors showed variable expression of TTF1, GATA3, CD10, and Calretinin. ER and PR were focally positive in only 2 cases, while others were negative. All cases demonstrated intact DNA mismatch repair proteins expression and wild-type p53 staining patterns. Molecular analysis performed in 10 cases identified pathogenic KRAS mutations in all tested samples. During a follow-up period of 1 to 75 months, 5 cases had recurrence, 1 patient remained alive with disease, and no disease-related death was reported.Conclusions:Ovarian mesonephric-like adenocarcinoma is an aggressive malignancy with a high potential for early recurrence and metastasis. Its frequent association with endometriosis and coexistence with other Müllerian tumors suggest a potential Müllerian origin. The tumor′s diverse morphological spectrum and common admixture with other tumor types often pose diagnostic challenges, making it difficult to distinguish from other gynecological malignancies. Therefore, accurate diagnosis of ovarian mesonephric-like adenocarcinoma is crucial for appropriate clinical management and prognostication.

Objective:To investigate the clinicopathological characteristics, immunophenotype and differential diagnosis of atypical forms of microglandular hyperplasia of the cervix (AMGH).Methods:A total of 29 cases of AMGH diagnosed at the Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China from January 2010 to December 2024 were analyzed. Relevant clinical and pathological data of the patients were collected using the electronic medical record system and medical records copied from the outside hospitals. The patients were followed up.Results:Among the 29 cases, 28 were consultation cases, 22 (79%) of the 28 cases were considered as glandular neoplastic lesions by the original institutions. The nature of the lesion was uncertain in 1 case, the diagnosis was suspicious for AMGH in another 1 case, and only 4 cases were clearly diagnosed as AMGH. The median age of the 29 patients was 44 (43, 48) years. Eighteen (62%) of the 29 cases presented as cervical polyp. Twelve of the 16 tested cases were negative for human papillomavirus. The pathological presentation was complex and diverse, including solid, trabecular, cribriform, and papillary patterns, forming pseudo-invasive structures. The glandular epithelium and proliferating reserve cells had diverse morphologies, which presented with abundant eosinophilic cytoplasm or clear cytoplasm. Signet-ring or hobnail cells were also seen. The nuclear atypia was mild, with 0-7 mitotic figures per 10 HPF. Immature squamous metaplasia was noted. The stroma showed edema, myxoid change and hyaline degeneration, accompanied by infiltration of acute and chronic inflammatory cells. Immunohistochemistry demonstrated that p16 was negative in 8/16 of the cases or patchy positive in the other 8/16, Ki-67 positive rate was less than 10% in all 16 cases, p53 was wild phenotype (9/9), and carcinoembryonic antigen was negative in 4/5 cases and focally positive in 1/5 cases, while p63 was positive in 6/9 of the tested cases.Conclusions:AMGH is a benign non-neoplastic lesion of the cervical glands. Half of the cases occur in perimenopausal or postmenopausal women, often presenting as polypoid hyperplasia or localized cervical thickening/elevation with a friable, fragile texture. Microscopically, it may show a pseudoinvasive pattern, making it prone to misdiagnosis as a malignant lesion. Thus, differentiation from cervical adenocarcinoma, clear cell carcinoma and microglandular endometrioid carcinoma is required. Integration of clinical history, immunohistochemistry and molecular testing may aid in the differential diagnosis.

Objective:To investigate the clinicopathological features, diagnosis and differential diagnosis of pseudocarcinomatous hyperplasia of the fallopian tubes.Methods:Sixteen cases of pseudocarcinomatous hyperplasia of the fallopian tubes diagnosed at Obstetrics and Gynecology Hospital of Fudan University from January 2011 to January 2024 were collected.The pathological sections were reviewed, the clinical and pathological data were consulted, and immunohistochemical examination was conducted along with follow-up.Results:The patients were aged from 19 to 57 years, with an average age of 41 and a median age of 38. Among the 16 cases, 4 were located in the right fallopian tubes, 6 in the left fallopian tubes, while the remaining cases presented bilaterally. The general manifestations were tubal edema, crispness and purulent secretion in the lumen. Morphologically, the fallopian tube mucosa exhibited a significant infiltration of neutrophils, lymphocytes and plasma cells. The epithelial cells of the fallopian tube displayed evident proliferation, stratification and disorganized arrangement leading to formation of small glandular cavity with back-to-back, fissure-like and sieve-like structures. Immunohistochemical analysis revealed positivity for CK7 and WT1, along with wild-type p53 expression, Ki-67 index ranged from 5% to 20%. During the follow-up period ranging from 1 to 156 months, all the patients remained free of disease.Conclusions:Pseudocarcinomatous hyperplasia of the fallopian tube is a rare non-neoplastic lesion, which can lead to epithelial hyperplasia and atypical hyperplasia. The most important significance of recognizing this lesion lies in avoiding misdiagnosis of fallopian tube cancer during intraoperative and postoperative pathological examination. This ensures that clinicians can administer correct clinical interventions.

Objective:To investigate the clinical and pathological characteristics of primary mucinous gland lesions of the fallopian tubes.Methods:The clinical data, pathomorphological characteristics and immunophenotype of 14 cases of primary mucinous gland lesions of the fallopian tube diagnosed at Obstetrics and Gynecology Hospital of Fudan University from 2015 to 2023 were analyzed retrospectively. In addition, a comprehensive review of relevant literature was conducted.Results:The age of 14 patients ranged from 53 to 83 years, with an average of 65 years. Among them, 13 cases exhibited unilateral involvement while one case showed bilateral presentation. Nine cases were mucinous metaplasia of the fallopian tube, four cases were invasive mucinous adenocarcinoma and one case was mucinous carcinoma in situ. Morphologically, mucinous metaplasia of the fallopian tube was focal, with or without inflammation. The cells of mucinous adenocarcinoma or mucinous carcinoma in situ exhibited characteristics indicative of gastrointestinal differentiation. Immunohistochemical analysis revealed diffuse positive expression of CK7, and negative expression of SATB2. CDX2 demonstrated positive staining in two cases. One case exhibited diffuse and strongly positive mutant expression of p53, whereas the remaining cases displayed wild-type expression. MUC6 showed diffuse or focally positive staining in mucinous gland lesions characterized by gastric differentiation. Some cases of mucinous adenocarcinoma of fallopian tube were subject to AB-PAS staining, resulting in red to purple cytoplasmic staining.Conclusions:Primary mucinous lesions of the fallopian tube are exceedingly uncommon. All cases of mucinous adenocarcinoma of fallopian tubes in this study exhibit the morphology and immunohistochemical characteristics of gastrointestinal differentiation. Mucinous metaplasia of the fallopian tube is a benign lesion of incidental finding, which is closely related to inflammation or gastric differentiation. Mucinous lesions of cervix, ovary and digestive tract are excluded in all patients, confirming the independent existence of mucinous lesions within fallopian tubes.