Adequacy of histopathology reports for breast cancer in New South Wales

Pathology reporting of breast cancer: trends in 1989-1999, following the introduction of mammographic screening in Western Australia

BACKGROUND

A survey of pathology reporting of breast cancer in Western Australia in 1989 highlighted the need for improvement. The current study documents (1) changes in pathology reporting from 1989 to 1999 and (2) changes in patterns of histopathological prognostic indicators for breast cancer following introduction of mammographic screening in 1989.

METHODS

Data concerning all breast cancer cases reported in Western Australia in 1989, 1994 and 1999 were retrieved using the State Cancer Registry, Hospital Morbidity data system, and pathology laboratory records.

RESULTS

Pathology reports improved in quality during the decade surveyed. For invasive carcinoma, tumour size was not recorded in 1.2% of pathology reports in 1999 compared with 16.1% in 1989 (p<0.001). Corresponding figures for other prognostic factors were: tumour grade 3.3% and 51.6% (p<0.001), tumour type 0.2% and 4.1% (p<0.001), vascular invasion 3.7% and 70.9% (p<0.001), and lymph node status 1.9% and 4.5% (p = 0.023). In 1999, 5.9% of reports were not in a synoptic/checklist format, whereas all reports were descriptive in 1989 (p<0.001). For the population as a whole, the proportion of invasive carcinomas <1 cm was 20.9% in 1999 compared with 14.5% in 1989 (p<0.001); for tumours <2 cm the corresponding figures were 65.4% and 59.7% (p = 0.013). In 1999, 30.5% of tumours were histologically well-differentiated compared with 10.6% in 1989 (p<0.001), and 61.7% were lymph node negative in 1999 compared with 57.1% in 1989 (p = 0.006). Pure ductal carcinoma in situ (DCIS) constituted 10.9% and 7.9% of total cases of breast carcinoma in 1999 and 1989, respectively (p = 0.01).

CONCLUSIONS

Quality of pathology reporting improved markedly over the period, in parallel with adoption of standardised synoptic pathology reports. By 1999, recording of important prognostic information was almost complete. Frequency of favourable prognostic factors generally increased over time, reflecting expected effects of mammographic screening.

Is centralized histopathology review necessary for screen-detected breast lesions?

To address quality requirements for breast pathology in the Australian screening programme, one breast cancer Screening and Assessment Service initiated a process of central pathologic review of all lesions detected through the service. The aim of this study was to measure concordance between the initial and review pathology, and to assess the merit of routine review. Concordance was measured by observed agreement and the kappa statistic for 267 women with 273 lesions. Concordance was excellent for the four classification schemes examined, good for the identification of benign lesions and hyperplasia, and excellent for the identification of DCIS or invasive carcinoma. For the sub-categorization of hyperplasias and invasive carcinomas concordance was good, but was poor for the sub-typing of DCIS. Initial and review concordance was acceptable, suggesting that disagreement among pathologists may not present a major impediment to the provision of dependable diagnoses. Full case review is unnecessary for benign lesions or invasive carcinoma, but should be maintained for DCIS and hyperplasias.

An audit of breast cancer pathology reporting in Australia in 1995

To measure the quality of pathology reporting of breast cancer and establish a baseline against which future changes can be measured, we audited item completeness in breast cancer reports in Australia in 1995 before the release of specific recommendations from the Australian Cancer Network. Tumour type and size were given in reports of invasive breast cancer for 93% of women, 70% had, in addition, grade and clearance of the margins while only 28% had all recommended information. The most complete items in reports were histological type of breast cancer (99.6% of cases), tumour size (94%, 95% confidence interval (CI) 92-95) and margins of excision (87%, 95% CI 85-89). Histological grade (84%, 95% CI 82-86 of cases) and presence or absence of ductal carcinoma in situ (DCIS) (79%, 95% CI 77-81) were less complete and vessel invasion (61%, 95% CI 58-63) and changes in non-neoplastic breast tissue adjacent to the breast cancer (68%, 95% CI 66-71) the least complete. Less than half the reports of DCIS reported on tumour size (49%, 95% CI 42-57), presence or absence of necrosis (41%, 95% CI 34-49) or nuclear grade (39%, 95% CI 31-46). Around 1500 reports were identified as issued by 147 laboratories and 392 pathologists; 69% of pathologists issued fewer than two reports a month in the audit. We concluded that infrequency of reporting may have contributed to incompleteness of reporting. In addition, we found significant variation across Australian states with some indication that reporting was consistently poor in one state. The audit highlighted areas for improvement for breast cancer reporting in Australia. Research evidence suggests that multifaceted strategies are needed to assist practitioners with implementing more uniform reporting standards.

Ductal carcinoma in situ. Part I: Definition and diagnosis

The frequency of diagnosis of ductal carcinoma in situ (DCIS) has increased in Australia, largely because of the national screening programme. Ductal carcinoma in situ presents a dilemma because of problems with its diagnosis and variations in reporting pathological and radiological findings, making it difficult to define optimal treatment and communicate information in a way that helps the patient understand the problems and make decisions. There is considerable inter-observer variation, particularly in differentiating low-grade DCIS from ductal hyperplasia, with or without atypia, but pathologists who participate in regular pathological review sessions vary less in their opinions. Mammography remains the main investigative tool for DCIS and the American College of Radiology has recommended standardized reports. A team approach is required for the removal and diagnosis of possible DCIS. Although the team may be best co-located in the one facility, this is not practical in many community hospital settings which lack on-site radiology and pathology services. The decision about how much breast tissue to remove will need to be made for each patient and depends on the size of the microcalcification and how suspicious the mammogram is for DCIS. We recommend the use of synoptic reports for DCIS, and we document the minimum factors that should be reported by pathologists. The evaluation and management of DCIS by a multidisciplinary team will allow the patient access to information required to make often difficult treatment decisions. In this paper, we review the literature about the natural history, pathology, cytology and radiology of DCIS and document the 20 critical steps required for the diagnosis of impalpable, mammographic microcalcifications suspected to be DCIS.