ANNALS OF IBADAN POSTGRADUATE MEDICINE
M.A. Ajani, O. Iyapo, A. Salami, and C.A. Okolo
Background: The ovary is a common site of involvement for metastases constituting 5-30% of all malignant ovarian neoplasms. Over half of these tumours are bilateral. The commonest sources are stomach, large bowel, appendix, breast, uterus (corpus and cervix) and lung.
Aim: The aim of this study was to determine the histopathological pattern of metastases to the ovary at the University College Hospital, Ibadan, South- western Nigeria.
Material and Methods: This was a retrospective study. All histologically confirmed cases of metastases to the ovary from the records and files of the Department of Pathology, University College Hospital (UCH), Ibadan between January 1991 and June 2013 were used for the study. These were cases diagnosed following total abdominal hysterectomy, total abdominal hystero-salpingo-oophorectomy, bilateral salpingo-oophorectomy, omentectomy, and multiple peritoneal biopsies and post-mortems at the University College Hospital between January 1991 and June 2013. Cases with inadequate clinical data and whose blocks and or slides could not be retrieved were excluded from the study. The data obtained were analysed using the Statistical Package for Social Sciences version 20
Results: There were 46 cases of metastases to the ovary constituting 5.3% of total ovarian neoplasms. Thirty (63.9%) cases were metastatic carcinomas with the affected patients’ age range of 20-79 years, and peak incidence within the age group of 30-39 years. Nineteen out of 30 cases of metastatic carcinomas were from adenocarcinoma of colon, 6 cases were from the gastric carcinoma while the remaining five cases were from the squamous cell carcinoma of the uterine cervix. Fifteen (31.9%) cases of Burkitt Lymphoma were found with patients with age range of 0-39 years, and the peak age of occurrence at the 2nd decade. The only case of metastatic Malignant Mixed Mullerian Tumour and metastatic Leiomyosarcoma were found in the 3rd and 4th decades of life respectively
Conclusion: This study has shown that metastases to the ovary occur in younger age groups in our environment. Therefore this study emphasizes that in young females with ovarian masses, the likelihood of metastatic tumours should not be discarded because, correct and precise diagnosis of secondary ovarian malignancy is critical as it has significant implication on the patients’ choice of management and prognosis.
Keyword: Histopathological, Ovarian neoplasms, Metastases, Ibadan
Dr. M.A. Ajani
Department of Pathology,
University College Hospital,
The ovary is a frequent metastatic site for primary gastrointestinal malignancies (colon and gastric carcinomas); primary cancers of breast, uterus and cervix; and haematologic malignancies (lymphomas and leukaemias).1-3 Secondary ovarian malignancies are relatively common ovarian cancers with prevalence range of 5% to 30%. This appears to be related to the frequency and patterns of dissemination of the primary cancers.2,4 In addition, secondary ovarian cancers also infrequently arises from metastasis of malignancies of the appendix, biliary tract, pancreas and the lungs.1 Metastatic ovarian cancers arises through spread from the primary malignancies via lymphatic or haematoge-nous or through transperitoneal or direct spreads.2-3
Krukenberg tumour had been inappropriately used to typify secondary ovarian neoplasm of gastrointestinal tract primary or all secondary ovarian cancers by some authors.1 Krukenberg tumour in the strict sense refers to metastatic ovarian cancers morphologically characterised by moderate multinodular growth and histopathological feature of diffusely infiltrating signet ring cells.2 Krukenberg tumours comprise of carcinoma arising from the stomach, colon, breast and other sites and are often bilateral.2,3,5
The works by Yakushiji et al and Fukuda et al suggested the likelihood of secondary ovarian cancer occurring in younger individuals in comparison to primary ovarian malignancy as the average age of the affected patients was about a decade less than that of patients with primary ovarian malignancy5,.6-7 Studies by Odone et al from the USA also reported increased frequency (18-27%) of metastasis of colorectal carcinomas to the ovaries in younger women (i.e. below 40 years) than in older patients.8 This is probably because gastric carcinomas have a typical propensity to metastasize to the ovary during pregnancy, with concomitant aggressive growth post-delivery.2-3 This could partly have accounted for the increased incidence of secondary malignancy in pre-menopausal women unlike in primary ovarian cancers.
Metastatic ovarian cancer may be suspected based on detailed clinical history, however, symptoms related to ovarian metastasis may sometimes be the first clinical manifestation of the primary malignancy, especially for gastrointestinal malignancies.3 Morphologic features that suggest secondary ovarian neoplasm include, bilaterality, small tumour size (i.e. <10cm), ovarian surface and superficial cortex involvement and histological features inconsistent with a primary ovarian malignancy.9-10 However, it must be noted that some primary ovarian malignancy such as serous papillary and endomerioid carcinoma can involve both ovaries.11 Ovarian endometrioid carcinoma and primary ovarian mucinous adenocarcinomas may share close histological features with a metastatic colorectal carcinoma.3,12-13 Tumour marker such as CA-125 and immunohisto-chemistry especially cytokeratin 7 and cytokeratin 20 may help in differential diagnosis of some secondary ovarian tumours. However, the interpretation of such results requires circumspection and due cognizance of the clinical details and total morphological pictures.14 Therefore, correct and precise diagnosis of secondary ovarian malignancy is critical because it has significant implication on the patients’ choice of management and prognosis since metastatic ovarian cancer signifies an advanced disease.14
Secondary ovarian neoplasm has a typically poor prognosis with median survival ranging from 1-3 years depending on the primary malignancy.15 Hence, the purpose of this study is to review the histopathological pattern of secondary ovarian neoplasm at the University College Hospital, Ibadan, South- western Nigeria over a twenty-two and half year period.
To the best of our knowledge, there has been no published local study in the available literature on this subject in our environment. Therefore, this study may serve to provide the first documented baseline data on the histopathological pattern of secondary ovarian neoplasm at the University College Hospital, Ibadan, and South- western Nigeria.
MATERIALS AND METHOD
This was a retrospective study. All histologically confirmed cases of metastatic neoplasms of the ovary in the records and files of the Department of Pathology, University College Hospital (UCH), Ibadan between January 1991 and June 2013 were used for the study. These were cases diagnosed following total abdominal hysterectomy, total abdominal hystero-salpingo-oophorectomy, bilateral salpingo-oophorectomy, omentectomy, and multiple peritoneal biopsies and post-mortems at the University College Hospital between January 1991 and June 2013. Cases with inadequate clinical data and those with missing slides and tissue blocks were excluded from this study. The haematoxylin and eosin stained histopathology slides of the available cases were reviewed and where necessary, new haematoxylin and eosin stained sections were obtained from archival paraffin blocks. Cases were re-classified to determine the histological subtypes according to the 2014 WHO histological classification of tumours of the ovary. The cases were all reviewed independently by two Histopathologists. The data obtained were analysed using the Statistical Package for Social Sciences version 20. Ethical clearance for the study was obtained from the Joint University of Ibadan/University College Hospital Ethical Review Committee. (Ethical approval number: UI/EC/12/0380)