Development and Validation of Prognostic Nomogram for Primary Peritoneal Serous Carcinoma Compared With FIGO Staging System: A Population-Based Study

Background

Primary peritoneal serous carcinoma (PPSC) is a rare tumor that lacks a prognostic prediction model. Our study aims to develop a nomogram to predict overall survival (OS) of PPSC patients.

Methods

Patients confirmed to have PPSC between 2004 and 2012 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. LASSO and multivariate Cox regression analyses were used to screen for meaningful independent prognostic factors to construct a nomogram model for 3-, 5-, and 10-year OS among patients with PPSC. The nomogram compared the discrimination, calibration, and net benefits with the International Federation of Gynecology and Obstetrics (FIGO) staging system of PPSC patients.

Results

Eight variables were selected to establish the nomogram for PPSC. The established nomogram performed significantly better than the FIGO staging system (p < 0.05). The 3-, 5-, and 10-year OS of PPSC was 0.498, 0.306, and 0.152, respectively. Patients of old age, widowed marital status, grade high, FIGO IIIB, IIIC, or IV, lymph node metastasis, no lymphadenectomy, no surgery, and no chemotherapy got higher score which corresponds with higher risk and lower OS. In the multivariate Cox regression analysis, age, histological grade, FIGO staging, lymph node metastasis, and lymphadenectomy (four or more) were identified as independent prognostic factors for PPSC.

Conclusions

PPSC patients have distinct characteristics with respect to their presentation and survival outcomes. A prognostic nomogram constructed by various clinical indicators can provide better and more accurate predictions for patients with PPSC.

Narrative review on serous primary peritoneal carcinoma of unknown primary site: four questions to be answered

Serous peritoneal papillary carcinoma (SPPC) represents a particular cancer of unknown primary (CUP) entity that arises in the peritoneal surface lining the abdomen and pelvis without a discriminative primary tumor site. In this review, we discuss the validity of SPPC as a distinct entity. Clinically, patients with SPPC are older, have higher parity and later menarche, are more often obese and probably have poorer survival compared to those with primary ovarian cancer. Pathologically, SPPC is more anaplastic and multifocal, unlike primary ovarian cancer which is commonly unifocal. Biologically, it presents a higher expression of proliferative signals and similar cell cycle and DNA repair protein expression. These differences hint towards SPPC and primary ovarian cancer being as a spectrum of disease. Patients with SPPC are traditionally managed similarly to stage III–IV ovarian cancer. The recommended approach integrates aggressive cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, and systemic chemotherapy to remove the macroscopic tumor, eradicate the microscopic residual disease, and control the microscopic metastasis. However, the available evidence lacks proper randomized or prospective studies on SPPC and is limited to retrospective series. The diligent identification of SPPC is warranted to design specific clinical trials that eventually evaluate the impact of the new therapeutics on this distinct entity.

Primary peritoneal serous papillary carcinoma: a case series

PURPOSE

To present the clinical and laboratory characteristics, as well as the management, of patients with primary peritoneal serous papillary carcinoma (PPSPC).

METHODS

This is a retrospective study of 19 patients with PPSPC who underwent debulking surgery followed by first line chemotherapy and were managed in Metaxa Memorial Cancer Hospital between January 2002 and December 2017.

RESULTS

The median age of the patients was found to be 66 years (range 44-76 years). Clinical presentation of PPSPC included abdominal distention and pain, constipation, as well as loss of appetite and weight gain. Two of the patients did not mention any symptomatology and the disease was suspected by an abnormal cervical smear and elevated CA125 levels respectively. Biomarkers measurement during the initial management of the patients revealed abnormal values of CA125 for all the participants (median value 565 U/ml). Human epididymis secretory protein 4 (HE4) and ratios of blood count were also measured. Perioperative Peritoneal Cancer Index ranged from 6 to 20. Optimal debulking was achieved in 5 cases. All patients were staged as IIIC and IVA PPSPC and received standard chemotherapy with paclitaxel and carboplatin, whereas bevacizumab was added in the 5 most recent cases. Median overall survival was 29 months.

CONCLUSION

PPSPC is a rare malignancy, the management of which should take place in tertiary oncology centers.

Inguinal Lymph Node Metastasis of a Primary Serous Papillary Carcinoma of the Peritoneum One Year after CRS and HIPEC

Background

Primary peritoneal serous papillary carcinoma is a rare malignant epithelial tumor which was first described in 1959. Peritoneal serous papillary carcinoma arises from the peritoneal epithelium and originates from a single or multicentric focus of the peritoneum involving the peritoneum of the abdomen and pelvis. The involvement of retroperitoneal lymph nodes occurs in 64% of the patients diagnosed with this malignancy. So far, there is no report about inguinal lymph node metastasis in this disease.

Case Report

We present a rare case of a 63-year-old female patient who developed singular inguinal lymph node metastasis 1 year after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy due to peritoneal serous papillary carcinoma. The lymph node metastasis was found by computed tomography (CT) scan and was resected and histologically confirmed. The postoperative course was uneventful, and the patient was discharged on postoperative day 1. The last CT scan 24 months after initial cytoreduction and 12 months after lymph node resection showed no further tumor recurrence.

Conclusion

This case report should raise the awareness of potentially unexpected presentation of extraperitoneal metastasis and highlights the importance of patient follow-up including clinical examination and CT scans of thorax/abdomen/pelvis following a systematic schedule.

Primary peritoneal serous carcinoma, an extremely rare malignancy: A case report and review of the literature

Primary peritoneal serous carcinoma (PPSC) is an extremely rare malignancy that was first described in 1959. This type of cancer arises from the peritoneal epithelium and is similar to serous ovarian carcinoma. A diagnosis of PPSC is typically made based on the Gynecology Oncology Group criteria; however, a correct differential diagnosis of PPSC is difficult preoperatively. The current study describes the case of a 66 year-old female patient presenting with abdomen distension. A computed tomography (CT) scan revealed abundant ascites in the abdominal cavity and omental infiltration. The results of positron emission tomography/CT showed hot uptake in the greater omentum. Furthermore, preoperative serum cancer antigen-125 levels were 1,032 U/ml. Upon surgical exploration, a whitish mass and nodule were found in the greater omentum. Therefore, omentectomy was performed. Pathological examination of the resected specimen revealed a diagnosis of PPSC. PPSC is extremely rare with few cases cited in the current literature. The present study describes a rare case of PPSC with a review of the literature.

When is it safe to omit surgery in primary peritoneal cancer with small volume disease?

Primary peritoneal cancer (PPC) is considered a very rare condition, with mesotheliomas deemed the only true PPC when considering the cellular content and embryological derivation of the peritoneum. However, in women, PPC are seen in much greater abundance than that in men and the type of cancer detected is often that of a serous epithelial carcinoma, histologically similar to serous ovarian carcinomas. The management is also similar, i.e. surgery and platin-based chemotherapy. The definition clinically of PPC is that of widespread carcinomatosis with normal-sized ovaries. The carcinomatosis is often extensive, and the only bulk disease may be within the omentum and achieving complete clearance of all disease at primary surgery unlikely. Thus, the concept of using chemotherapy as the main strategy is a reasonable approach and may well be the best single therapeutic option in some patients. This paper reviews the data on PPC and how this approach could be assessed.