Mucinous cystadenocarcinoma of the breast harbours TRPS1 expressions and PIK3CA alterations

AIMS

Breast mucinous cystadenocarcinoma (BMCA) is a rare tumour recently recognised as a distinct entity by the World Health Organisation Tumour Classification Series. BMCA is a triple-negative tumour that lacks specific immunohistochemical markers; therefore, distinguishing it from mimickers such as ovarian and pancreatic cystadenocarcinomas requires careful clinicopathological correlation. Due to its rarity, little is known about the molecular alterations that underlie BMCA.

METHODS AND RESULTS

In this study, we used immunohistochemical staining methods to investigate TRPS1 (trichorhinophalangeal syndrome type 1) expression in BMCA and compare it to expression in ovarian and pancreatic mucinous cystadenocarcinomas. We also collected tumour samples from three BMCA patients for molecular analysis by MALDI-TOF mass spectrometry, real-time polymerase chain reaction, whole exome sequencing and fluorescence in-situ hybridisation. TRPS1 immunoreactivity was found only in BMCA tumour cells and not in the ovarian and pancreatic counterparts. One of the three BMCA tumours also showed a PIK3CA hot-spot mutation, which was confirmed by whole genome next-generation sequencing (NGS). No KRAS, NRAS, BRAF or AKT mutations were found.

CONCLUSIONS

To our knowledge, this is the first demonstration of TRPS1 expression in BMCA patients and the first identification of a PIK3CA hotspot mutation in these tumours. These findings provide insights into the molecular mechanisms underlying BMCA tumorigenesis and suggest a potential drug target for this rare and poorly understood cancer.

Primary Mucinous Cystadenocarcinoma of the Breast: Clinicopathological Analysis of a Case and Difficulties Encountered in a Biopsy

Background. With <40 case reports published in the English literature, mucinous cystadenocarcinoma of the breast is quite rare compared to its counterparts in the ovary, pancreas, and appendix. The purpose of this case report is to enrich scientific data by sharing the clinicopathological features of this new and extremely rare entity and present possible difficulties encountered in the biopsy materials. Case Report. A 34-year-old female patient presented with the complaint of white discharge from her left nipple lasting 8 months. Physical and radiological examination of the patient revealed a mass in the lower quadrant of the left breast and tru-cut biopsy was performed. The diagnosis of invasive breast carcinoma of no special type was reported. After neoadjuvant chemotherapy, left subcutaneous mastectomy and left sentinel lymph node biopsy were performed. Microscopic evaluation of the mastectomy material revealed a tumor consisting of stratified columnar cells with basally located nuclei and intracytoplasmic mucin, showing papillary structures and tufting toward the lumen. Peripheral myoepithelial cells were not identified with p63 and calponin immunohistochemistry. The diagnosis of mucinous cystadenocarcinoma was given through histomorphological and immunohistochemical evaluations. Conclusion. Clarifying unknown points about this rare malignancy of the breast and understanding the tumor biology is possible through evaluation of case reports. For this purpose, our case of primary mucinous cystadenocarcinoma is presented and its clinicopathological features are briefly discussed.

Primary Retroperitoneal Serous Cyst Adenoma: A Case Report and Literature Review

Primary retroperitoneal serous cyst adenomas (PRSCs) are extremely rare thin-walled cystic lesions whose pathogenesis is not well understood. Clinical presentation varies depending on the lesion's size and location, i.e., larger lesions compress adjacent organs, giving the impression of malignancy. Although advances in imaging techniques enable to identify various characteristics of retroperitoneal cystic lesions, there are no pathognomonic signs to confirm the diagnosis. The exact diagnosis is based on the histology after complete surgical excision. An open surgical approach is considered the traditional method of complete resection; however, laparoscopic techniques have increasingly been employed. Diagnostic aspiration is discouraged due to the potential risk of seeding if the lesion is malignant. We present the case of a 51-year-old woman who underwent complete excision of a large right retroperitoneal cyst, histologically confirmed as PRSC with a review of the background and management options of this phenomenon.

Malignant Transformation in a Mature Cystic Teratoma of the Ovary: An Unusual Case Presentation

Mature cystic teratoma is the most common type of ovarian germ cell tumor. Malignant transformation is a rare complication in 1-3% of cases, especially in post-menopausal women. The most common type of malignant transformation by histology is squamous cell carcinoma, followed by adenocarcinoma, carcinoid tumor, melanoma, and sarcoma. Diagnostic difficulties exist due to non-specific findings. No clinical, radiological, or biological signs are specific to malignant transformation. Most patients are diagnosed in advanced stages and have poorer outcomes. Staging of the disease is an important prognostic factor, with early diagnosis and treatment being critical for improved survival. Here, we report a rare case of mature cystic teratoma presented as torsion, postoperatively diagnosed as mature cystic teratoma with borderline mucinous cystadenoma and focal intra-epithelial malignant transformation.

Dramatic Response to Carboplatin Plus Paclitaxel in Pancreatic Mucinous Cystadenocarcinoma with Liver Metastasis

Mucinous cystic neoplasm (MCN) of the pancreas is a rare cystic tumor occurring in the pancreatic body and tail in young to middle-aged women that is pathologically characterized by an ovarian-like stroma. Chemotherapy for recurrent/advanced pancreatic MCN has been based on chemotherapy regimens for pancreatic ductal adenocarcinoma, but the prognosis is poor. We herein report a 37-year-old woman with pancreatic mucinous cystadenocarcinoma with liver metastasis that responded dramatically to carboplatin plus paclitaxel therapy (CBDCA+PTX). CBDCA+PTX may be a treatment option for recurrent/advanced pancreatic MCN with an ovarian-like stroma.

Genetic profile of primary mucinous cystadenocarcinoma of the breast-A case report

Primary mucinous cystadenocarcinoma of the breast is a rare neoplasm with few reports in the literature. Here, we report for the first time a comprehensive genetic profile of a primary mucinous cystadenocarcinoma of the breast, using next-generation sequencing 580 cancer-associated gene panel. Mutations in TP53, RB1, and BAP1 were identified. The findings suggest that this tumor is driven mostly by abnormalities in tumor suppressor genes, primarily involved in cell cycle control and chromatin remodeling. Molecular characterization of additional primary mucinous cystadenocarcinomas of the breast is warranted and might provide information related to its biology and behavior.

Primary Mucinous Cystadenocarcinoma of the Breast: A Rare Case Report With Review of Literature

Primary mucinous cystadenocarcinoma (MCA) of the breast is a rare variant of breast carcinoma known to have a favorable prognosis despite showing a basal-like phenotype. We describe a case of MCA breast in a 45-year-old female with a palpable mass in the breast. On the basis of the histopathological and immunohistochemical evaluation of a lumpectomy specimen with the absence of mass anywhere else on whole-body imaging, a diagnosis of primary MCA was rendered. Mismatch repair protein evaluation showed this tumor to be microsatellite stable. Molecular testing revealed the absence of Kirsten rat sarcoma viral oncogene homolog (KRAS), neuroblastoma RAS viral oncogene homolog (NRAS), and v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations. To date only 27 cases of MCA breast have been reported. To the best of our knowledge, ours is the first case documenting diffuse Cytokeratin 20 (CK20) positivity, microsatellite stability, and the absence of KRAS, NRAS, and BRAF mutations in these tumors. The rarity of this tumor further evokes an interest in this case. A better understanding of the disease warrants a review of more cases with longer follow-ups.

Primary mucinous cystadenocarcinoma of the breast: a clinicopathologic analysis of one case and review of the literature

OBJECTIVE

To explore the clinicopathologic features and differential diagnosis of breast primary mucinous cystadenocarcinoma (MCA).

METHODS

Pathological characteristics and immunophenotype of one case of MCA were analyzed. Literature was reviewed.

RESULTS

Grossly, the area of the tumor cut surface was gelationous. Microscopcally, the tumor was composed of variably sized cystic spaces lined by mucus-rich tumor cells with single columnar, stratified appearance and papillary formation. The degree of cytologic atypia varied from region to region. The tumor cells were positive for CK7, GATA3, negative for CK20, ER, PR and HER2. Most peripheral myoepithelial cells were negative for P63 and SMMHC.

CONCLUSIONS

MCA is a rare primary breast cancer and strikingly similar to ovarian, pancreatic and gastrointestinal counterparts. The diagnosis cannot be made until the metastatic lesion is ruled out. On the other hand, the biologic behavior of MCA is reportedly favorable despite a high proliferation index and triple negative biomarker status. Therefore, the role of adjuvant chemotherapy or radiation is questionable.

Autophagy promotes malignant migration and invasion via miR-224-5p/BCL2 in pancreatic mucinous cystadenocarcinoma MCC1 cells

The prognosis of invasive pancreatic mucinous cystadenocarcinoma (MCC) is poor, and the molecular mechanism underlying its development remains unclear. The present study aimed to explore the potential role of autophagy in pancreatic MCC. The results demonstrated an increase in autophagy signaling in pancreatic MCC tissues and the MCC1 cell line compared with adjacent tissues and normal human pancreatic ductal epithelium (HPDE) cells. In addition, abnormal autophagy activation facilitated the migration and invasion of MCC1 cells. MicroRNA (miR)-224-5p expression levels were significantly higher in MCC1 cells compared with those in HPDE cells. Treatment with rapamycin further demonstrated that high levels of autophagy elevated miR-224-5p expression in MCC1 cells in a time-dependent manner. BCL2 was identified as a downstream target gene of miR-224-5p, which binds to the 3′-untranslated region of BCL2. In addition, the results of the present study demonstrated that BCL2 knockdown reversed the inhibition of autophagy mediated by the miR-224-5p inhibitor. To the best of our knowledge, this is the first study to evaluate the role of autophagy in pancreatic MCC. Thus, these results suggested that autophagy may be hyperactivated in pancreatic MCC. In addition, the present study identified a positive feedback loop between autophagy signaling and miR-224-5p, which may promote the aggressive migration and invasion of MCC1. These results may provide a new insight into the relationship between autophagy and tumor metastasis in pancreatic MCC.

Mammary synchronous mucinous cystadenocarcinoma and columnar cell mucinous carcinoma: a case report

Mucin-producing carcinomas are unusual primary malignancies of breast, and constitute about 1-4 percent of total breast cancer. The mammary mucin producing carcinomas are divided into 4 histologic subtypes according to WHO classification, including mucinous carcinoma, mucinous cystadenocarcinoma (MCA), columnar cell mucinous carcinoma (CCMC), and signet ring cell carcinoma. However, the synchronous primary MCA and CCMC of breast is a very rare case presentation. The case reported a 56-year-old female, who presented with right mammary lumps and nipple discharge about 1 year. Imaging examinations revealed multiple cystic and solid nodules in upper outer quadrant of right breast, associated with ectatic ducts. Serum levels of tumor markers were normal. Right mammary lumpectomy revealed mucinous carcinoma, modified radical mastectomy, and lymph node dissection were carried out. For neoplastic cells, ER and PR were positive, HER2 (1+) was negative, Ki67 was low expression (3-5%). There was no metastatic carcinoma in lymph nodes (0/8). Modified radical mastectomy and lymph node dissections were carried out. Tamoxifen was chosen for adjuvant therapy. After a 3 month follow up, the patient survived without recurrences and distant metastasis. We report the first synchronous primary MCA and CCMC of breast with molecular subtype of Luminal A.

Primary retroperitoneal mucinous cystadenocarcinoma with transition from the mesothelium

INTRODUCTION

Mucinous cystic neoplasms are uncommon among the tumors that develop in the retroperitoneum. We report a case of primary retroperitoneal mucinous cystadenocarcinoma with pathological considerations.

CASE PRESENTATION

A 47-year-old woman complaining of abdominal discomfort presented at our hospital. Abdominal computed tomography and magnetic resonance imaging showed a large cystic tumor with small solid nodules located in the right retroperitoneum. The tumor was completely removed and the microscopic findings were consistent with primary retroperitoneal mucinous cystadenocarcinoma. Two years after the surgery, the patient is alive without recurrence of the tumor.

CONCLUSION

The microscopic findings suggested that the primary retroperitoneal mucinous cystadenocarcinoma developed from the metaplasia of the remnant coelomic epithelium. A complete tumor resection that includes the adjacent peritoneum is important to prevent local recurrence.

Mucocele of the appendix presenting as an exacerbated chronic tubo-ovarian abscess: A case report and comprehensive review of the literature

RATIONALE

Appendiceal mucocele is a rare entity of mucinous cystic dilatation of the appendix. It has no typical clinical presentation and is considered a potentially premalignant condition.

PATIENT CONCERNS

We present a case of accidental intraoperative finding of an appendiceal mucocele in a 54-year old woman that clinically presented with an exacerbated chronic tubo-ovarian abscess.

DIAGNOSES

Trans-vaginal ultrasonography showed an encapsulated, oval, unilocular mass above the uterus with a heteroechogenic structure, homogeneous fluid content, and smooth regular walls without inner proliferation. The histopathologic diagnosis was consistent with an appendiceal cystadenoma.

INTERVENTIONS

The patient underwent a simple appendectomy.

OUTCOMES

There were no clinical, biochemical or imaging signs of the disease recurrence at 6 months follow up.

LESSONS

To our knowledge, this is the only well-documented case of appendiceal mucocele mimicking exacerbated chronic tubo-ovarian abscess reported in the literature. Awareness of a rare entity such as an appendiceal mucocele, which is frequently misdiagnosed as a potential cause of acute abdomen, is necessary for the appropriate management strategy in order to prevent complications.

Predicting Underlying Neoplasms in Appendiceal Mucoceles at CT: Focal Versus Diffuse Luminal Dilatation

OBJECTIVE. The purpose of this study was to determine whether a novel morphologic characteristic of appendiceal mucoceles at CT-focal distal appendiceal dilatation with a segment of morphologically normal appendix proximally-could predict an underlying neoplastic pathologic abnormality before surgery and histopathologic assessment. MATERIALS AND METHODS. A retrospective study was performed that assessed CT cases from 2012 through 2014. Cases showing morphologic features of a mucocele were identified and categorized into two subgroups: focal distal dilatation with a segment of normal appendix proximally and generalized appendiceal dilatation. The underlying histopathologic diagnosis for each case was assessed and categorized as neoplastic or nonneoplastic. Several additional morphologic findings were also assessed. RESULTS. Forty-nine cases with confirmed histopathologic diagnoses were identified. Of those, 20 of 23 (87.0%) cases with the finding of focal distal dilatation had an underlying neoplastic cause, whereas 14 of 26 (53.8%) cases with generalized dilatation had an underlying neoplastic cause (p = 0.012). The findings of periappendiceal fat stranding (p = 0.004), mural calcification (p = 0.006), and degree of luminal dilatation (p = 0.002) also reached statistical significance. When seen in combination with focal distal dilatation, the positive predictive value for underlying neoplasm approached or reached 100%. CONCLUSION. Our study shows that isolated focal distal appendiceal dilatation with a segment of morphologically normal appendix proximally is significantly associated with an underlying neoplastic histopathologic cause. When seen in combination with mural calcification, a diameter of more than 2 cm, and absence of periappendiceal stranding, an underlying neoplastic cause is strongly suggested.

Pseudomyxoma Peritonei as a First Manifestation of KRAS-Mutated Urachal Mucinous Cystadenocarcinoma of the Bladder: A Case Report

Only 28 cases of pseudomyxoma peritonei (PMP) arising from urachal neoplasms have been reported. We report one example of this extremely rare disease with KRAS mutational status in its spectrum of pathology. A 45-year-old woman presented with urachal frankly invasive mucinous cystadenocarcinoma confined to the dome of the bladder, which clinically manifested as PMP and was not detected at the first surgery. The primary tumour was revealed 6 months later because of its recurrence as PMP. Microscopic investigation revealed tubular adenoma and cystadenocarcinoma communicating with the bladder lumen and transitioning from the urachal urothelium to the mucinous epithelium. A urachal remnant was identified near the neoplasm. On immunohistochemistry, the tumour proved positive for CK7, CK20, CEA, and CDX2. Staining for β-catenin revealed expression in both the cytoplasm and cell membrane. Mismatch repair protein expression was normal. Somatic KRAS-mutation (G12V) was revealed in tubular adenoma, cystadenocarcinoma, and mucinous carcinoma peritonei and may play an oncogenic role in the malignant transformation of urachal mucosa and the development of PMP.

Pancreatic pseudocyst or mucinous cystadenocarcinoma of pancreas? A diagnostic dilemma

Pancreatic cystic neoplasm is difficult to distinguish from pseudocyst as clinical and radiological evidences may not be sufficient to make an accurate diagnosis. This may result in misdiagnosis with inappropriate management. Hence, every effort should be made for their distinction to avoid internal drainage procedures for neoplasms instead of extirpation.

A giant mucinous cystadenocarcinoma of the appendix: a case report and review of the literature

BACKGROUND

Mucinous cystadenocarcinoma is the second most common etiology of appendiceal mucocele. We report a relatively rare case of a giant appendiceal mucocele caused by mucinous cystadenocarcinoma, which occupied the entire abdomen of an adult woman.

CASE PRESENTATION

A 63-year-old woman presented with a chief complaint of abdominal distention. Imaging studies showed a giant cystic mass occupying her entire abdomen. Laparotomy confirmed a giant appendiceal mucocele, and the patient underwent ileocecal resection. A mucinous deposit was not found in her abdominal cavity, and the ovaries were grossly normal bilaterally. The pathological diagnosis was mucinous adenocarcinoma with a low-grade mucinous neoplasm that invaded the subserosa. Regional lymph node metastasis was not found. She has had recurrence-free survival for 5 years.

CONCLUSIONS

The present case is the largest appendiceal cystadenocarcinoma ever reported. The optimal treatment of an appendiceal neoplasm requires further research based on consensus terminology of an appendiceal mucocele.

Report of a case: Retroperitoneal mucinous cystadenocarcinoma with rapid progression

INTRODUCTION

Retroperitoneal mucinous cystic neoplasms are uncommon, and little is known about the etiology of the disease. Malignant forms of these are extremely rare. Here, we report a case of primary retroperitoneal mucinous cystadenocarcinoma (PRMC), which demonstrated unexpectedly aggressive progression despite finding only a limited area of adenocarcinoma.

PRESENTATION OF CASE

A 62-year-old woman with a complaint of abdominal discomfort was admitted to the hospital. Abdominal CT and MRI showed multiple large retroperitoneal cysts dislocating the right kidney nearly to the center of the abdomen. Transabdominal resection of the cysts was performed. Those cysts contained 1100ml of mucinous fluids in total. Cytological examination of those fluids revealed no malignant cells. The cyst wall was lined with mucinous epithelial cells, and contained some ovarian-type stroma. Also, there was a focal area of adenocarcinoma in the cyst wall, and the lesion was diagnosed as primary retroperitoneal mucinous cystadenocarcinoma. Eight months later, the patient developed lumbar bone metastasis. Chemotherapy with S-1, an oral fluoropyrimidine, and docetaxel had been begun immediately; however, the disease had rapidly spread in the retroperitoneum. Eventually, the patient died of the disease 15 months after surgery.

DISCUSSION

Retroperitoneal mucinous cystic neoplasms are considered to be metaplasia of embryonal coelomic epithelium. Complete excision without rupture is essential. However, variance of biological aggressiveness might exist in PRMCs.

CONCLUSION

Retroperitoneal mucinous cystadenocarcinoma is a rare tumor, and it is urgently necessary to elucidate the etiology of an effective therapy for the disease.

A rare pleural mucinous cystadenocarcinoma mimicking loculated empyema initially: A case report

We report a case of pleural mucinous cystadenocarcinoma which was mistaken to be a loculated empyema on chest CT. To the best of our knowledge, this entity has never been previously reported in literature.

A case of Krukenberg carcinoma metastasized from colon cancer resembling mucinous cystadenocarcinoma of the ovary

We report a case of a 44-year-old woman with bilateral ovarian carcinoma that had metastasized from the colon and mimicked primary mucinous cystadenocarcinoma. Macroscopically, both ovarian tumors were large, multiloculated cystic masses with abundant mucinous content. Histologically, they were lined with mucinous epithelium with mild to moderate nuclear atypia and showed stromal invasion and surface involvement. At first, the tumors were diagnosed as bilateral primary ovarian mucinous cystadenocarcinomas. However, three months after surgery, a large villous tumor was discovered in the ascending colon by colonoscopic examination and was surgically resected. Histologically, the colonic tumor was a villous adenomatous tumor with invasive components of mucinous adenocarcinoma composed of well-differentiated adenocarcinoma and exhibited abundant extracellular mucin production. As a villous adenomatous component was present in the mucosal area, the colonic tumor was considered a primary tumor. Therefore, the original diagnosis of bilateral ovarian tumors was revised for consistent with metastasis from the colon carcinoma, in line with the findings of immunohistochemistry and loss of heterozygosity analysis. This case highlights the importance of considering the possibility of metastatic tumors from the gastrointestinal tract in the diagnosis of mucinous ovarian tumors.

Primary retroperitoneal mucinous cystadenocarcinoma in a male patient: a rare case report

BACKGROUND AND AIM

Primary retroperitoneal mucinous cystadenocarcinoma (PRMC) is a very rare tumor. To date, less than 50 cases of PRMC have been described in the English literature. Description of the case: We report a case of PRMC in a male patient who presented with chronic lower back pain for 8 months. Computed tomography (CT) showed a retroperitoneal mass in the right abdominal cavity, measuring approximately 4cm × 3cm. At laparotomy, a predominantly cystic, well-encapsulated mass was observed in the right retroperitoneum. The mass was excised without rupture. The final diagnosis of PRMC was confirmed by pathology.

CONCLUSION

To our knowledge, this is the 5th published case report of a PRMC in a male patient. No other reported cases of PRMC in Chinese men are available in the literature. A literature review of PRMC in the English language literature is also provided.

Mucinous cystadenocarcinoma of the appendix in which contrast-enhanced ultrasonography was useful for assessing blood flow in a focal nodular lesion in the tumor cavity: A case report

A 63-year-old woman was admitted to hospital with pain in the right lower quadrant. Abdominal computed tomography (CT) revealed a 60-mm cystic mass at a site corresponding to the appendix. The mass wall on the appendicular ostium was thickened and enhanced by contrast, while calcification was observed in the mass wall on the appendicular tip. No projection was observed in the mass cavity. On abdominal ultrasonography (US), the mass wall on the appendicular ostium was thickened and projections were observed at two sites in the mass cavity. On contrast-enhanced US (CEUS), only one of these projections was enhanced. Based on the thickened and contrast-enhanced wall of the mass on the appendicular ostium on CT and US, as well as the contrast enhancement of a projection on US, the mass was diagnosed as mucinous cystadenocarcinoma of the appendix. Ileocecal resection was subsequently performed on day 10. A detailed examination of the surgical specimen revealed carcinoma cells in the mass wall on the appendicular ostium. The contrast-enhanced projection was identified as granulation tissue that had grown to come into contact with the tumor, while the non-contrast-enhanced projection was identified as solidified mucus. US enabled successful visualization of projections in the mass cavity that were not visible on abdominal CT. CEUS also proved useful for assessing blood flow in these projections.

International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma

INTRODUCTION

Adenocarcinoma is the most common histologic type of lung cancer. To address advances in oncology, molecular biology, pathology, radiology, and surgery of lung adenocarcinoma, an international multidisciplinary classification was sponsored by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society. This new adenocarcinoma classification is needed to provide uniform terminology and diagnostic criteria, especially for bronchioloalveolar carcinoma (BAC), the overall approach to small nonresection cancer specimens, and for multidisciplinary strategic management of tissue for molecular and immunohistochemical studies.

METHODS

An international core panel of experts representing all three societies was formed with oncologists/pulmonologists, pathologists, radiologists, molecular biologists, and thoracic surgeons. A systematic review was performed under the guidance of the American Thoracic Society Documents Development and Implementation Committee. The search strategy identified 11,368 citations of which 312 articles met specified eligibility criteria and were retrieved for full text review. A series of meetings were held to discuss the development of the new classification, to develop the recommendations, and to write the current document. Recommendations for key questions were graded by strength and quality of the evidence according to the Grades of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

The classification addresses both resection specimens, and small biopsies and cytology. The terms BAC and mixed subtype adenocarcinoma are no longer used. For resection specimens, new concepts are introduced such as adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure lepidic growth (AIS) or predominant lepidic growth with ≤ 5 mm invasion (MIA) to define patients who, if they undergo complete resection, will have 100% or near 100% disease-specific survival, respectively. AIS and MIA are usually nonmucinous but rarely may be mucinous. Invasive adenocarcinomas are classified by predominant pattern after using comprehensive histologic subtyping with lepidic (formerly most mixed subtype tumors with nonmucinous BAC), acinar, papillary, and solid patterns; micropapillary is added as a new histologic subtype. Variants include invasive mucinous adenocarcinoma (formerly mucinous BAC), colloid, fetal, and enteric adenocarcinoma. This classification provides guidance for small biopsies and cytology specimens, as approximately 70% of lung cancers are diagnosed in such samples. Non-small cell lung carcinomas (NSCLCs), in patients with advanced-stage disease, are to be classified into more specific types such as adenocarcinoma or squamous cell carcinoma, whenever possible for several reasons: (1) adenocarcinoma or NSCLC not otherwise specified should be tested for epidermal growth factor receptor (EGFR) mutations as the presence of these mutations is predictive of responsiveness to EGFR tyrosine kinase inhibitors, (2) adenocarcinoma histology is a strong predictor for improved outcome with pemetrexed therapy compared with squamous cell carcinoma, and (3) potential life-threatening hemorrhage may occur in patients with squamous cell carcinoma who receive bevacizumab. If the tumor cannot be classified based on light microscopy alone, special studies such as immunohistochemistry and/or mucin stains should be applied to classify the tumor further. Use of the term NSCLC not otherwise specified should be minimized.

CONCLUSIONS

This new classification strategy is based on a multidisciplinary approach to diagnosis of lung adenocarcinoma that incorporates clinical, molecular, radiologic, and surgical issues, but it is primarily based on histology. This classification is intended to support clinical practice, and research investigation and clinical trials. As EGFR mutation is a validated predictive marker for response and progression-free survival with EGFR tyrosine kinase inhibitors in advanced lung adenocarcinoma, we recommend that patients with advanced adenocarcinomas be tested for EGFR mutation. This has implications for strategic management of tissue, particularly for small biopsies and cytology samples, to maximize high-quality tissue available for molecular studies. Potential impact for tumor, node, and metastasis staging include adjustment of the size T factor according to only the invasive component (1) pathologically in invasive tumors with lepidic areas or (2) radiologically by measuring the solid component of part-solid nodules.

Mucinous cystadenocarcinoma of the pancreas - outcome following different modes of treatment

BACKGROUND

Mucinous cystadenocarcinomas (MCAC) of the pancreas are rare tumors. When localized to the pancreas alone, surgical resection is mostly associated with a favorable prognosis. The potential value of palliative treatment with chemotherapy for irresectable disease is scarcely described though. The aim of this study was to describe a single-center series of patients with MCAC of the pancreas focusing on the outcome following different treatment strategies.

METHODS

15 patients, 10 females and 5 males, with histologically or cytologically verified MCAC, were divided into three groups: surgical resection (n=7), chemotherapy (n=5) and no treatment (n=3).

RESULTS

There was no obvious difference in gender distribution between the subgroups. A tendency towards higher age was seen in the group without treatment, as was a larger tumor size as compared to the chemotherapy group. Patients were administered chemotherapy and the group without treatment seemed to present with the same prevalence of metastatic disease (3/5 and 2/3, respectively). All patients in the group without treatment died after in median 1 month following pathological diagnosis. One patient in the chemotherapy group was alive at 9-month follow up, and the others survived a median of 11 months. In the surgically treated group, 4/7 were alive at follow-up of a median of 154 months. Of the three deceased patients who had survived 44, 53 and 151 months, respectively, two had microscopically non-radical resection.

CONCLUSIONS

MCAC of the pancreas is, when locally confined and without metastases, associated with fairly good prognosis after surgical resection. In inoperable patients and for metastatic disease, outcome is poor.