Boost dosage to the excision site following conservative surgery for breast cancer: it's easy to miss!

Surgical haemoclips have been left in situ in 27 consecutive patients conservatively operated on for early breast cancer by two surgeons in Newcastle, New South Wales, to demarcate the limits of the excision cavity for accurate postoperative irradiation. As anticipated, the position of these clips varied widely in relation to the patient's recollection of the position of the original lump, the surgical notes, and the surgical scar. In addition the dimensions of the clipped area also varied considerably. So great was the variation in position of the clips that incomplete coverage of the excision cavity in the 'coronal' (en face) plane using an electron field could have occurred in an estimated 10/24 (42%) evaluable cases had surgical clips not been left in situ. Depth of the surgical clips below the skin surface also varied markedly between patients. In 19/26 (73%) evaluable cases the clips were observed to be sited 3 cm or more below the skin surface, while in only 5/26 (19.2%) were the clips found to be 2 cm or less deep to the surface. Had a 9 MeV beam from our Clinac 1800 been used to treat all the cases, a major underdose of the excision cavity would have been likely in 21/26 (81%) evaluable cases. This figure would be improved to 11/26 (42%) had a 12 MeV beam been used--still a very high figure. Neither of these points have received much attention in the literature. This small study sounds a distinct warning and needs to be repeated on a larger scale.

Factors related to the presentation of patients with thick primary melanomas

OBJECTIVE

To identify any characteristics of patients that are associated with presentation with thick primary melanoma.

DESIGN

This was a retrospective survey of the clinical records of 1300 patients attending the Newcastle Melanoma Unit. Characteristics of 131 patients with thick melanomas (defined as 3 mm or greater in thickness) were compared with those of 543 patients with thin melanomas (defined as 0.75 mm or less in thickness). Comparisons were made using contingency table analysis, Wilcoxon rank sum tests, log rank analysis and logistic regression.

SETTING

The Newcastle Melanoma Unit is a tertiary referral centre for the treatment of primary melanoma.

PATIENTS

We surveyed all 1300 patients attending the Newcastle Melanoma Unit over the years 1981-1990. They represented approximately 90% of the patients in the Hunter region of New South Wales who developed melanoma during this period. Excluded from analysis were 39 patients with occult primary melanomas, 79 with multiple primary melanomas, 51 with primary melanomas of unknown thickness and seven with incomplete records, leaving 1124 patients in the study.

MAIN OUTCOME MEASURES

These were selected before the results were known. The hypothesis was generated following analysis of the data.

RESULTS

Patients with thick primary melanoma were more likely to be men (68% men and 32% women in the thick melanoma group, compared with 45% and 55% respectively in the thin melanoma group, P less than 0.005) over 60 (75% were over 50 years of age in the thick group versus 33% in the thin melanoma group, P less than 0.001) with nodular melanoma (62%, versus 2% in the thin melanoma group, P less than 0.001) and with melanoma on the head and neck (27%, versus 12% in patients with thin melanoma, P less than 0.005). The time from detection of a change in skin to diagnosis was not longer for those with thick compared to those with thin melanomas.

CONCLUSION

The greatest problem of those with thin melanomas.

CONCLUSION

The greatest problem of detecting melanoma at an early (surgically curable) stage appears to be in patients over the age of 50 who have nodular melanoma, particularly in the head and neck.