Frequency and histogenesis of pelvic retroperitoneal lymph node inclusions of the female genital tract. An immunohistochemical study of 34 cases

Intraoperative Appearance of Endosalpingiosis: A Single-Center Experience of Laparoscopic Findings and Systematic Review of Literature

Background: Endosalpingiosis is assumed to be the second most common benign peritoneal pathology after endometriosis in women. Although recent studies indicate a significant association with gynecologic malignancies, many underlying principles remain unclear. This work aimed to systematically describe the intraoperative appearance of endosalpingiosis. Methods: Data and intraoperative videos of patients with histologically verified endosalpingiosis were retrospectively reviewed. The main outcome measures were macroscopic phenotype and anatomical distribution. Additionally, a systematic review searching PubMed (Medline) and Embase was conducted. Results: In the study population (n = 77, mean age 40.2 years (SD 16.4)), the mean size of lesions was 3.6 mm and the main visual pattern was vesicular (62%). The most frequent localization was the sacrouterine ligaments (24.7%). In the systematic review population (n = 1174 (210 included studies overall), mean age 45.7 years (SD 14.4)), there were 99 patients in 90 different studies with adequate data to assess the appearance of the lesions. The mean size of the lesions was 48.5 mm, mainly with a cystic visual pattern (49.5%). The majority of the lesions affected the ovaries (23.2%), fallopian tubes (20.4%), or lymph nodes (18.5%). Comparing this study to the literature population, the main differences concerned the size (p < 0.001) and main visual patterns (p < 0.001) of lesions. Conclusions: The usual intraoperative findings of endosalpingiosis appeared less impressive than described in the literature. In our study population, lesions of a few millimeters in size with a vesicular appearance were mostly seen, most frequently in the sacrouterine ligament area. Intraoperative recognition by the gynecologic surgeon and histologic diagnosis should play an important role in further understanding this entity, scientifically and clinically.

The Diagnostic Accuracy of an Intraoperative Frozen Section Analysis and Imprint Cytology of Sentinel Node Biopsy Specimens from Patients with Uterine Cervical and Endometrial Cancer: a Retrospective Observational Study

Sentinel node biopsy (SNB) may be a decision-making tool for function preservation surgery, including radical trachelectomy and ovary preservation in the treatment of cervical and endometrial cancer. The intraoperative diagnosis is important for guiding treatment decisions for patients with these conditions. Three hundred seventy-one patients with cervical and endometrial cancer received SNB with an intraoperative frozen section analysis and imprint cytology. The sentinel node was cut in half, parallel to the longest axis, to obtain the maximum section area. After performing imprint cytology, one half was used to create a frozen section. The specimen was cut at 2-mm intervals into 5-μm-thick sections, which were subjected to hematoxylin and eosin staining. The diagnostic accuracy of intraoperative frozen section analyses and imprint cytology was compared to the final pathological diagnosis. Among 951 detected sentinel nodes, 51 nodes were found to be positive in the final pathological diagnosis. The sensitivity of a frozen section analysis, imprint cytology and the combination of the two modalities was 76.5%, 72.6%, and 92.2%, respectively. The specificity of a frozen section analysis and imprint cytology was 100%. The negative predictive value of a frozen section analysis and imprint cytology was 98.7% and 98.5%, respectively. In these settings, the accuracy of the frozen section analysis and imprint cytology in the evaluation of SNB specimens was considered acceptable; however, the sensitivity of the combined approach was higher in comparison to when a frozen section analysis or imprint cytology was performed alone.

Role of one-step nucleic acid amplification (OSNA) to detect sentinel lymph node low-volume metastasis in early-stage cervical cancer

INTRODUCTION

Growing evidence in the literature supports the accuracy of sentinel lymph node (SLN) biopsy in early-stage cervical cancer. One-step nucleic acid amplification (OSNA) is a rapid assay able to detect cytokeratin 19-mRNA in SLNs, and it can be used for intra-operative detection of low-volume metastases. The aim of this study was to evaluate the rate of low-volume metastasis in SLNs detected by OSNA in patients with early-stage cervical cancer. Secondary aims were to define the sensitivity and the negative predictive value of SLN biopsy assessed with OSNA.

METHODS

After IRB approval, consecutive patients who underwent surgery for International Federation of Gynecology and Obstetrics stage IA1 with lymph-vascular space involvement to IB1 between November 2017 and July 2019 and had SLN biopsy and pelvic lymphadenectomy were included. SLNs were detected with indocyanine-green cervical injection and sent intra-operatively for OSNA.

RESULTS

Eighteen patients underwent SLN assessment with OSNA and systematic pelvic lymphadenectomy in the study period. Four (22.2%) patients had unilateral and 14 (77.8%) had bilateral mapping. OSNA detected micro-metastasis in 6/18 (33.3%) patients. All micro-metastases were detected in patients with bilateral SLN mapping. The sensitivity and negative predictive value of SLN in detecting lymph node metastasis with OSNA calculated per pelvic sidewall were 85.7% and 96.1%, respectively. The false negative rate in mapped sidewalls was 14.3%.

DISCUSSION

This is the first series entirely processing SLNs for OSNA in early-stage cervical cancer. OSNA is able to intra-operatively detect low-volume metastases in SLNs. Further studies are necessary to confirm the accuracy of this technique and to assess survival implications of low-volume metastases detected by OSNA.

One-Step Nucleic Acid Amplification (OSNA): A fast molecular test based on CK19 mRNA concentration for assessment of lymph-nodes metastases in early stage endometrial cancer

INTRODUCTION

The aim of the current study is to evaluate the detection rate of micro- and macro-metastases of the One-Step Nucleic Acid Amplification (OSNA) compared to frozen section examination and subsequent ultra-staging examination in early stage endometrial cancer (EC).

MATERIAL AND METHODS

From March 2016 to June 2016, data of 40 consecutive FIGO stage I EC patients were prospectively collected in an electronic database. The sentinel lymph node mapping was performed in all patients. All mapped nodes were removed and processed. Sentinel lymph nodes were sectioned and alternate sections were respectively examined by OSNA and by frozen section analysis. After frozen section, the residual tissue from each block was processed with step-level sections (each step at 200 micron) including H&E and IHC slides.

RESULTS

Sentinel lymph nodes mapping was successful in 29 patients (72.5%). In the remaining 11 patients (27.5%), a systematic pelvic lymphadenectomy was performed. OSNA assay sensitivity and specificity were 87.5% and 100% respectively. Positive and negative predictive values were 100% and 99% respectively, with a diagnostic accuracy of 99%. As far as frozen section examination and subsequent ultra-staging analysis was concerned, we reported sensitivity and specificity of 50% and 94.4% respectively; positive and negative predictive values were 14.3% and 99%, respectively, with an accuracy of 93.6%. In one patient, despite negative OSNA and frozen section analysis of the sentinel node, a macro-metastasis in 1 non-sentinel node was found.

CONCLUSIONS

The combination of OSNA procedure with the sentinel lymph node mapping could represent an efficient intra-operative tool for the selection of early-stage EC patients to be submitted to systematic lymphadenectomy.

Ductal Carcinoma In Situ Simultaneously Involving the Breast and Epithelial Inclusions in an Ipsilateral Axillary Lymph Node

Benign cystic epithelial inclusions with squamous, glandular, or Müllerian phenotypes are known to occur in the axillary lymph nodes of patients with benign and malignant breast disease. Careful evaluation of hematoxylin and eosin-stained slides and correlation with the histologic findings in the ipsilateral breast are paramount in evaluation of suspected benign inclusions. In this case of ductal carcinoma in situ (DCIS) of the breast in a 73-year-old woman, DCIS also involved epithelial inclusions in an ipsilateral axillary lymph node. The recognition of these benign epithelial elements, and awareness that they can be involved by DCIS, is crucial to avoid the overdiagnosis of metastatic carcinoma.

Endometriosis with an aberrant immunophenotype: Challenging differential diagnosis of glandular lesions in the pelvic lymph nodes

CASE REPORT

We describe an unusual case of pelvic lymph node endometriosis with an aberrant immunophenotype mimicking metastasis of adenocarcinoma. A 37-year-old patient with a history of invasive cervical adenocarcinoma stage pT1a2 is presented. Due to insufficient loop electrosurgical excision procedure (LEEP) conization, total laparoscopic hysterectomy with pelvic lymphadenectomy was indicated. Intraoperatively, the diagnosis of deep infiltrating endometriosis of parametrial ligament and vesicouterine pouch, endometrioma of the left ovary and Allen Master's syndrome was suspected; the patient had no history or clinical symptoms of endometriosis. A PubMed search of similar cases was followed by a comparison to this case and discussion of the differential diagnosis of glandular lesions in the pelvic lymph nodes is reported.

RESULTS

Histological investigation showed no residual neoplasia; the diagnosis of endometriosis was confirmed. An interesting microscopic finding was represented by a solitary glandular lesion in one pelvic lymph node. Using immunohistochemistry, it was demonstrated that there was a complete loss of oestrogen and progesterone receptor expression (unlike parametrial ligament endometriosis). The diagnosis of endometriosis was based on the presence of endometrial stroma; malignancy was excluded by bland cytomorphologic features and results of immunohistochemical examination.

CONCLUSIONS

This type of aberrant of the endometriotic gland immunophenotype has never been presented in the scientific literature before. This finding plays a significant role from the pathology standpoint and, perhaps more importantly, from the clinical standpoint. An asymptomatic patient with a correct diagnosis of lymph node endometriosis did not undergo excessive treatment for false positive diagnosis of metastatic cervical adenocarcinoma.

Endosalpingiosis of Axillary Lymph Nodes: A Rare Histopathologic Pitfall with Clinical Relevance for Breast Cancer Staging

Establishment of accurate axillary lymph node status is of essential importance in determining both prognosis and the potential need for adjuvant therapy in patients with invasive breast cancer. Axillary lymph node heterotopias can in some cases result in overdiagnosis of metastatic disease. Nodal endosalpingiosis is perhaps the least commonly reported type of axially lymph node heterotopia. We herein illustrate a case in which second opinion pathologic interpretation combined with ancillary immunohistochemical studies allowed for a specific diagnosis of axillary nodal müllerian-type inclusions, confirming ypN0 staging and resulting in appropriate disease management and prognostication.

Endocervicosis involving axillary lymph nodes: first case report

The occurence of Mullerian epithelial inclusions, especially endosalpingiosis, in pelvic and other subdiaphragmatic lymph nodes is well known. In contrast, Mullerian inclusions involving lymph nodes above the diaphragm is uncommon, although occasional cases of endosalpingiosis have been reported. We report a case of benign Mullerian inclusions of mucinous endocervical type (endocervicosis) coexistent with metastatic breast-infiltrating ductal carcinoma in 2 axillary lymph nodes. The inclusions exhibited diffuse positive staining with CK7, PAX8, CA125, and estrogen receptor and were WT1 negative. To our knowledge, this is the first report of endocervicosis involving supradiaphragmatic lymph nodes. Close morphologic examination and immunohistochemistry assists in distinguishing Mullerian inclusions from metastatic adenocarcinoma.

Epithelial and pancreatic choristoma in bovine lymph nodes

Lymph nodes from 186 cows were evaluated as part of a bovine tuberculosis eradication programme. The mediastinal lymph nodes of 13 animals contained atypical structures. In 12 cases (6.45%) these consisted of multiple epithelial structures and, in one case, of pancreatic-like tissue. Immunohistochemistry (IHC) revealed that the epithelial structures were consistent with respiratory epithelium and with ectopic pancreatic tissue, respectively. To the best of our knowledge these are the first histological and immunohistochemical descriptions of epithelial and pancreatic choristomas in bovine lymph nodes.

Epithelioid cells in mediastinal lymph nodes of cattle without cancer

Epithelioid cells are found in lymph nodes in cases of metastatic carcinoma; however, epithelioid cells with benign features have also been discovered incidentally in lymph nodes. Epithelioid cells were observed in mediastinal lymph nodes of cattle without cancer during routine diagnostic necropsy. To explain this finding, the authors evaluated the prevalence and histopathologic, immunohistochemical, and ultrastructural features retrospectively using mediastinal lymph nodes from 110 cattle and found that 66 of the lymph nodes contained epithelioid cells. In all 66 nodes, most of the epithelioid cells were individual or aggregated in nodal sinuses; in 21 nodes, some epithelioid cells formed tubular structures. The individual and aggregated epithelioid cells were mostly considered to be mesothelial in origin by immunohistochemical and ultrastructural examination; presumably, they entered the lymph nodes via lymphatic vessels, because they were found in afferent lymphatic vessels and nodal sinuses. Although the presence of epithelioid cells in lymph nodes prompts suspicion of metastatic carcinoma, the epithelioid cells in these bovine lymph nodes did not disrupt nodal architecture, lacked atypia or mitotic figures, and did not invade nodal parenchyma.

Recent Developments on the Significance and Pathogenesis of Lymph Node Involvement in Ovarian Serous Tumors of Low Malignant Potential (Borderline Tumors)

In approximately 27% of patients that were surgically staged for ovarian serous borderline tumors (ovarian serous tumors of low malignant potential), regional lymph nodes, most commonly the pelvic and paraaortic groups, display morphologically similar epithelial clusters. Lymph nodes above the diaphragm may also be involved. Lymph node involvement does not adversely impact the overall survival of patients with ovarian serous borderline tumors, but there is controversy as to whether this finding is associated with a decrease in recurrence-free survival. Nodular aggregates of epithelium greater than 1 mm in maximum dimension, as compared with all other patterns of nodal involvement, have been associated with reduced recurrence-free survival. The lymph nodes may also be the site of recurrence and/or progression to carcinoma of an ovarian serous borderline tumor. Recent molecular and morphologic data suggest that although most nodal implants are indeed metastatic from their synchronous ovarian neoplasms, a small subset arise de novo from nodal endosalpingiosis. The precise mechanistic basis for how these noninvasive neoplasms achieve nodal metastases is unclear. However, because most patients with nodal metastases also have peritoneal implants, tumors that are ovary-confined and without ovarian surface involvement are rarely associated with nodal involvement, microinvasive borderline tumors frequently display lymphatic vessel involvement yet show a remarkably low frequency of nodal involvement, in conjunction with the recent finding that node-positive and node-negative tumors display no significant differences in lymphatic vessel density, suggest that the route of spread to lymph nodes in most cases is via the peritoneal and not tumoral lymphatics.

Lymph node involvement and lymphovascular invasion in deep infiltrating rectosigmoid endometriosis

OBJECTIVE

To analyze the lymph node involvement by endometriotic foci in rectosigmoid endometriosis and to correlate it with clinical and histological parameters including the presence of lymphovascular invasions, which could explain this lymph node involvement.

DESIGN

A prospective study of 26 consecutive cases of rectosigmoid endometriosis between January 2005 and January 2007.

SETTING

A multidisciplinary study including clinical and pathological data.

PATIENT(S)

Twenty-six patients with symptomatic rectosigmoid endometriosis.

INTERVENTION(S)

Laparoscopic surgery with pathological analysis of each specimen.

MAIN OUTCOME MEASURE(S)

Involvement of lymph nodes by endometriotic foci was correlated with the size and the wall layers affected by endometriotic lesions, the number of lymph nodes retrieved, and the presence of lymphovascular invasions demonstrated by D2-40, a specific antibody to lymphatic vessels.

RESULT(S)

Lymph node involvement by endometriosis was observed in 11 of the 26 patients (42.3%) and correlated with the size of the lesions, the number of lymph nodes retrieved, and the presence of lymphovascular invasions, which were observed in 36.3% of cases.

CONCLUSION(S)

Our data confirm that lymph node involvement by endometriotic foci is a frequent event in rectosigmoid endometriosis and may result at least partially from a lymphatic spread of the disease.

Benign pulmonary epithelial inclusions within the pleura: a case report

Background

The normal visceral and parietal pleura are composed of a mesothelium-lined layer of fibrous connective tissue, consisting predominantly of collagen and elastin fibers, with interspersed nerves, lymphatics, and blood vessels. There is no normal epithelial component to the pleura, and the histologic finding of epithelial cells within pleural tissue typically indicates the presence of a malignant process. The one documented exception to this rule is the occasional occurrence of endometriotic implants, which can result in cyclic thoracic symptomatology and occasionally even hemothorax.

Case Presentation

We present a case of seemingly benign epithelial inclusions within the pleura of a sixty year-old male patient who underwent exploratory thoracotomy and subsequent resection of bullous emphysematous blebs. Examination of the surgical specimen revealed well-defined nests of benign-appearing epithelial cells in glandular configurations at multiple sites within the pleura. These cells were immunopositive for TTF-1 and CK7 and immunonegative for calretenin, CK20, and CEA, indicating pulmonary epithelial derivation. Six months after resection, the patient is in stable health, with no clinical or radiologic evidence of bronchogenic carcinoma.

Conclusion

To our knowledge, this is the first report of benign pulmonary epithelial inclusions within pleural tissue. It is important to be aware that benign pleural inclusions occur, so as to avoid confusion with more serious processes in a population of patients who may have oncologic risk factors.

Negative sentinel lymph node accurately predicts negative status of pelvic lymph nodes in uterine cervix carcinoma

OBJECTIVE

The significance of negative sentinel lymph nodes (SLN) is important in the staging and treatment of melanoma and a few other cancers, but is controversial in uterine cervix carcinoma. Our study was aimed at correlating the SLN status in cervical carcinoma with non-sentinel lymph nodes (non-SLN), in a uniform and well controlled population.

METHODS

This study includes 36 patients with stage I and IIA cervical carcinoma and bilaterally negative SLN on final pathology. SLN were identified using blue dye and radioisotopic techniques. Frozen section examination was performed for all SLN; the rest of the tissue was formalin fixed and paraffin embedded. The protocol used for SLN was also applied for non-SLN. For each block, six 4-micro m thick sections were cut at 40 micro m intervals and stained with H and E; an additional section taken between the 3rd and 4th levels was imunostained using AE1/AE3 cytokeratin.

RESULTS

The mean age for the study population was 39 years (range 25-76); the number of SLN ranged from 2 to 6 (mean 2.7) and the non-SLN from 8 to 49 (mean 23) per case. No metastasis was found in any SLN and non-SLN by step sections and IHC.

CONCLUSION

Our study demonstrates that bilaterally negative SLN on final pathology accurately predict the absence of metastases in non-SLN in cervical carcinoma. If confirmed by larger trials, these results may influence the clinical management of early cervical cancer.

Micrometastases detected by cytokeratin 19 expression in sentinel lymph nodes of patients with early-stage cervical cancer

The purpose of this study was to detect micrometastases in sentinel lymph nodes (SLNs) by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) analyses for cytokeratin 19 (CK19) expression in early-stage cervical cancer. One hundred twenty-five SLNs were collected from 46 patients with early-stage cervical cancer. Conventional histopathologic techniques revealed 14 metastatic SLNs from 11 out of 46 patients. CK19 expression was detected by RT-PCR and IHC in all the 125 SLNs. Cervical cancer tissues from nine patients and five pelvic lymph nodes from the patients without tumor were utilized as positive and negative controls, respectively. All the metastastic SLNs on conventional histopathologic techniques were positive by either RT-PCR or IHC analyses, while all the positive controls were positive and all the negative controls were negative as expected. Of 35 patients without metastatic SLNs on conventional histopathologic techniques, the detection rate of micrometastases was 42.85% by RT-PCR and 20% by IHC analyses. RT-PCR and IHC were more sensitive to identify micrometastases in SLNs of patients with early-stage cervical cancer than routine pathology. These findings demonstrated that micrometastasis could be identified by molecular technique such as RT-PCR and IHC analyses for CK19 expression. RT-PCR was more sensitive to detect micrometastases in SLNs than IHC in patients with early-stage cervical cancer. Therefore, molecular assessment of the SLNs may be a valuable tool to complement routine histologic examination of cervical cancer. The importance of micrometastases in SLNs is under close clinical observation to determine whether it can be used as a predicting factor to help us make decision whether to proceed with whole-pelvic lymph node dissection or as a prognostic factor for clinical outcome.

Sister Joseph umbilical nodule coexisting with endometriosis from endometrial carcinoma

A 58-year-old woman was diagnosed with endometrial carcinoma. Total hysterectomy, bilateral salpingo-oophorectomy and paraaortic and a pelvic lymph node dissection were performed. The cytology of peritoneal fluid was negative. There was no peritoneal dissemination except umbilical nodule. A peritoneal 2.0x1.5 cm umbilical nodule was also resected. The nodule was identified as a metastasis from endometrial cancer with endometriosis. The pelvic lymph nodes also showed metastatic lesion with endometriosis. Our case showed that endometriosis coexisted with umbilical and pelvic lymph nodal metastatic lesions from endometrial cancer. This fact suggests that the mode of metastasis to the umbilicus via lymph flow from endometrial cancer is the same as that for endometriosis.

Ectopic Decidua of Pelvic Lymph Nodes: A Potential Diagnostic Pitfall

Ectopic decidua is one of several benign lymph node inclusions that have been increasingly documented in the literature, most often in postmortem examinations of pregnant woman and recently in pregnant women with cervical squamous cell carcinoma. Although lacking clinical significance of its own, the major diagnostic implication would be misdiagnosis as metastatic carcinoma in the lymph node. Intraoperative frozen sections are often performed prior to radical hysterectomy, leading to a potential alteration of therapy if metastatic carcinoma is identified in the lymph nodes. We report such a case of a pregnant woman with cervical squamous cell carcinoma requiring lymphadenectomy and hysterectomy, in which the intraoperative frozen section of a pelvic lymph node with ectopic decidual change was mistakenly identified as metastatic carcinoma. Its histologic resemblance to carcinoma and location within subcapsular sinuses, compounded with the fact that ectopic lymph node decidua is not commonly seen in routine practice, can lead to this diagnostic pitfall. We review the literature regarding ectopic decidua, its presence in lymph nodes, and its pathogenesis, as well as review the literature on benign lymph node inclusions.

Ectopic mesothelial cell proliferation in cervical lymph nodes after severe ovarian hyperstimulation syndrome

OBJECTIVE

To report a case of ectopic mesothelial proliferation in cervical lymph nodes after severe ovarian hyperstimulation syndrome.

DESIGN

Case report.

SETTING

University-affiliated teaching hospital.

PATIENT(S)

A 42-year-old woman underwent a successful IVF attempt and developed severe ovarian hyperstimulation syndrome and pathologically enlarged cervical lymph nodes.

INTERVENTION(S)

Paracentesis, cervical lymph node biopsy followed by cytology, histology, and immunohistochemistry.

MAIN OUTCOME MEASURE(S)

Resolution of symptoms, pregnancy outcome, correct pathological diagnosis.

RESULT(S)

Paracentesis resulted in resolution of symptoms of ovarian hyperstimulation. The diagnosis of ectopic mesothelial proliferation in cervical lymph nodes was made after immunohistochemical examination of cervical lymph nodes. The pregnancy progressed normally, and at 40 weeks the patient spontaneously delivered a healthy son weighing 3,060 g.

CONCLUSION(S)

This case describes ectopic mesothelial cell proliferation localized in and around cervical lymph nodes occurring at 9 weeks' gestation in a patient who earlier developed severe ovarian hyperstimulation syndrome 10 days after ET. Ectopic mesothelial cell proliferation in lymph nodes is an extremely rare event, and this is the first case described after ovarian hyperstimulation. Familiarity with this event is important for the clinician as well as for the pathologist in preventing the misdiagnosis of malignancy.

Hyperplastic mesothelial cells in subpleural lymph nodes mimicking metastatic carcinoma

We describe a patient with a history of poorly differentiated adenocarcinoma of the stomach in whom hyperplastic mesothelial cell inclusions were present in subpleural lymph nodes. The involved lymph nodes were embedded in a lipoma in the parietal pleura. The role of histochemistry and immunohistochemistry in the differentiation of these inclusions from metastatic carcinoma is discussed.

Intraperitoneal serous adenocarcinoma: a critical appraisal of three hypotheses on its cause

OBJECTIVE

Serous ovarian, Fallopian tube, and peritoneal adenocarcinomas are remarkably similar, both in their morphology, as well as in their clinical behavior. Despite extensive clinical and fundamental research, controversy still exists on the origin of serous female adnexal tumors. Difficulties in identification of site of origin at late stage the of disease at detection, when ovary, Fallopian tube, and the abdominal cavity are usually all involved, in addition to their macroscopic and microscopic resemblance, are major causes of this debate. In 3 hypotheses, 3 possible tissues of origin are proposed: the ovarian surface epithelium, the Fallopian tube epithelium, and the secondary Mullerian system.

STUDY DESIGN

We searched for all peer-reviewed articles and reviews that examined "serous ovarian carcinoma," "Fallopian tube carcinoma," "Mullerian system," "ovarian surface epithelium," "tubal epithelium," and "peritoneal." We included only articles that could give information on the origin of serous carcinomas. Additional articles were added by examining references of overview articles in relevant fields.

RESULTS

Discussed are the experimental data underlying these hypotheses.

CONCLUSION

An attempt is made to integrate the 3 hypotheses into a comprehensive model of serous intraperitoneal adenocarcinogenesis. It can be concluded that the Fallopian tubes play a major role in the development of female serous cancer.

Immunohistochemical analysis of retroperitoneal Müllerian cyst

Retroperitoneal cysts are uncommon diseases, and benign nonneoplastic Müllerian cysts are extremely rare among the known cases. We report a case of a 35-year-old woman with a retroperitoneal Müllerian cyst with the tubal type of epithelium. The patient presented with a large (20 cm in diameter), palpable abdominal mass. This multilocular cystic mass was resected from the retroperitoneum between the descending colon and the left renal fascia. Histologically, it was lined by monolayered low-cuboidal to columnar cells without atypia that resembled tubal epithelium, including cilia. Loose fibrous tissue and incomplete smooth muscle bundles were identified beneath the epithelium of the lining. Immunohistochemical tests showed that the lining cells were strongly positive for cytokeratins (CKs) (polyclonal, 7, 18, CAM 5.2, AE1/AE3), epithelial membrane antigen, cancer antigen 125, progesterone receptor, and estrogen receptor. The lining cells were also occasionally weakly positive for CK5/6. They tested negative for CK20, carcinoembryonic antigen, calretinin, and CD 10.

Adenocarcinoma of the lower third of the rectum: metastases in lymph nodes smaller than 5 mm and occult micrometastases; preliminary results on early tumor recurrence

BACKGROUND

The number of examined lymph nodes and metastases in lymph nodes smaller than 5 mm (small lymph nodes) are a determining factor in the stage of rectal cancer although the clinical significance of occult micrometastases is controversial. We are reporting our preliminary results on the identification and prognostic utility of metastases in small lymph nodes and occult micrometastases.

METHODS

We searched small metastatic lymph nodes in 101 cases of adenocarcinoma of the lower third of the rectum. We used the manual technique to dissect mesorectal fat and occult micrometastases in the lymph nodes of 52 Dukes' A and B patients, using a pool of anticytokeratin antibodies.

RESULTS

Forty-five percent of the metastatic lymph nodes were smaller than 5 mm in diameter and determined the Dukes' stage in 15 (30.6%) of 49 Dukes' C patients. Occult micrometastases were found in 21 (40.4%) patients: five recurred but vascular invasion, positive distal margin of the rectum, and positive circumferential margin of the mesorectum were present.

CONCLUSIONS

Small metastatic lymph nodes, vascular invasion, positive distal margin of the rectum, and positive circumferential margin of the mesorectum were found to be more important than occult micrometastases in predicting early recurrence of rectal cancer.

Association of lymphangioleiomyomatosis (LAM) with endosalpingiosis in the retroperitoneal lymph nodes: report of two cases

We report 2 patients in whom pulmonary lymphangioleiomyomatosis (LAM) affected the retroperitoneal lymph nodes and was associated with endosalpingiosis. These lesions were large, encapsulated masses with multiple cysts containing chylous fluid. Both were characterized by proliferating LAM cells that formed fascicles separated by slit-like channels. Some cysts were lined by ciliated epithelium resembling that of Fallopian tubes. Other cysts were lined either by flattened endothelial cells or by a mixture of these cells and epithelial cells. Many LAM cells gave a positive reaction with HMB-45 antibody. Most LAM cells in fascicles were reactive for alpha-smooth muscle actin and desmin. In 1 patient, many of the epithelial cells and some of the subjacent LAM cells were positive for estrogen and progesterone receptors. In conclusion, immunostaining with HMB-45 antibody and markers for smooth muscle cells can be helpful in the evaluation of problems in the differential diagnosis of lesions of extrapulmonary LAM, particularly those involving the genital system.

K-ras mutations in Müllerian inclusion cysts associated with serous borderline tumors of the ovary

OBJECTIVE

Müllerian inclusion cysts (MIC) are small benign appearing glands that are occasionally noted in lymph nodes and peritoneal biopsies. They occur most frequently in women with serous ovarian tumors, with borderline tumors (SBOT) having a higher incidence than invasive cancers. The aim of this study was to examine whether MIC and SBOT have identical K-ras mutations, which would suggest that they are related. Methods. Six patients in whom adequate tissue was available from SBOT, MIC, and normal tissue were identified from a consecutive series of patients with SBOT who underwent lymph node sampling from 1992 to 1997 at Duke University Medical Center. DNA extraction was performed using laser capture microdissection. Exon 1 of the K-ras gene was amplified using PCR and subjected to single-strand conformation analysis to screen for mutations. Shifted bands were sequenced to confirm the presence of mutations.

RESULTS

Mutations in codon 12 of K-ras were found in three of six (50%) SBOT. In two of these three cases, the identical mutation was found in the SBOT and the MIC (gly to val in both cases), but not in the corresponding normal DNA. In one case, a mutation was seen in the ovarian tumor (gly to asp), but not in the corresponding MIC.

CONCLUSIONS

Mutations in codon 12 of the K-ras gene are a hallmark of serous borderline tumors. The presence of identical K-ras mutations in some SBOT and their associated MIC suggests that they are related processes. Both may arise due to a field effect, or alternatively some MIC may represent metastases from the primary ovarian tumor.

Some mullerian inclusion cysts in lymph nodes may sometimes be metastases from serous borderline tumors of the ovary

Glandular inclusions that appear morphologically benign are occasionally found in lymph nodes as well as in peritoneal and omental biopsies. In patients with gynecologic malignancies, the nature and significance of these mullerian inclusion cysts (MIC) present a diagnostic challenge with regard to whether they are benign and incidental or are related to the coincident tumor for which surgery is being performed. Sixty-two cases of MIC were prospectively identified during a 6-year period. The frequencies were calculated and stratified by lymph node chain distribution, primary tumor site, and primary tumor type. MIC appeared as small cysts lined by a serous (mullerian)-type, cytologically bland, cuboidal to columnar epithelium with a simple architecture. Among 62 women, MIC was found in lymph nodes (27 cases), pelvic peritoneum (19 cases), omentum (16 cases), bowel serosa (9 cases), uterine serosa (8 cases), and parametrial connective tissues (4 cases). Among a set of 417 consecutive cases in which lymphadenectomy was performed, 46 (11%) women had MIC. The MIC involved multiple sites (26 cases in the peritoneum/omentum and 27 in lymph nodes). The primary tumor was in the ovary in 32 of the 46 women with MIC (70%) and of these, 17 were borderline serous (53%). Sixty-two of 6,154 lymph nodes examined contained MIC (1.0%). 3.2% of nodes contained MIC in which the primary tumor arose in the ovary, but only 0.1% with either endometrial or cervical tumors (chi2, p <0.00001). The lymph nodes most often involved by MIC were from para-aortic sites (40%), which reflect the primary drainage route from the ovary. Not uncommonly, neighboring areas in the same lymph node group with MIC disclosed separate foci of obvious metastatic borderline tumor (4 of 10; 40%). In summary, the increased frequency of MIC in lymph nodes sampled for primary ovarian malignancies suggests that MIC in some cases, rather than being benign, incidental inclusions, are more likely bland-appearing forms of metastatic tumor. The preponderance of inclusions occurs with serous ovarian tumors of borderline malignancy, and the inclusions are overrepresented in the lymph nodes that primarily receive drainage from the ovary.

Florid cystic endosalpingiosis with tumor-like manifestations: a report of four cases including the first reported cases of transmural endosalpingiosis of the uterus

Four cases of endosalpingiosis presenting as masses that resembled neoplasms are described in women 20, 41, 43, and 74 years of age. Each case was referred in consultation because of difficulties in pathologic diagnosis. In two patients, multiple cysts that involved the serosal surfaces of the uterus and adnexa in one case, and the colon, rectosigmoid, pelvic sidewalls, and the cul-de-sac in the other, were excised. In the other two cases, hysterectomy was performed for an enlarged cystic cervix in one case and presumed uterine leiomyomas in the other. In both of these cases, the uterine cervix and lower part of the uterine corpus were extensively involved by multiple cysts on gross examination, and in one of them, a frozen section of the cervical lesion was initially interpreted as "suspicious for invasive minimal deviation adenocarcinoma." On microscopic examination, benign endosalpingiotic glands and cysts were found in all four cases, with striking transmural involvement of the uterine cervix and lower uterine segment and contiguous corpus in the two cases with uterine involvement. The latter two cases are the first examples, to our knowledge, of endosalpingiosis involving the wall of the uterus; the differential diagnosis in these cases includes minimal deviation adenocarcinoma and florid tubal metaplasia with cystification. The four cases in this report, and rare previously reported cases, indicate that although usually a microscopic finding, endosalpingiosis can rarely present as a clinically or grossly evident mass that can be confused with a neoplasm.