Fat/water ratios measured with diffuse reflectance spectroscopy to detect breast tumor boundaries.

Recognition of the tumor during breast-conserving surgery (BCS) can be very difficult and currently a robust method of margin assessment for the surgical setting is not available. As a result, tumor-positive margins, which require additional treatment, are not found until histopathologic evaluation. With diffuse reflectance spectroscopy (DRS), tissue can be characterized during surgery based on optical parameters that are related to the tissue morphology and composition. Here we investigate which optical parameters are able to detect tumor in an area with a mixture of benign and tumor tissue and hence which parameters are most suitable for intra-operative margin assessment. DRS spectra (400-1600 nm) were obtained from 16 ex vivo lumpectomy specimens from benign, tumor border, and tumor tissue. One mastectomy specimen was used with a custom-made grid for validation purposes. The optical parameter related to the absorption of fat and water (F/W-ratio) in the extended near-infrared wavelength region (~1000-1600 nm) provided the best discrimination between benign and tumor sites resulting in a sensitivity and specificity of 100 % (excluding the border sites). Per patient, the scaled F/W-ratio gradually decreased from grossly benign tissue towards the tumor in 87.5 % of the specimens. In one test case, based on a predefined F/W-ratio for boundary tissue of 0.58, DRS produced a surgical resection plane that nearly overlapped with a 2-mm rim of benign tissue, 2 mm being the most widely accepted definition of a negative margin. The F/W-ratio provided excellent discrimination between sites clearly inside or outside the tumor and was able to detect the border of the tumor in one test case. This work shows the potential for DRS to guide the surgeon during BCS.

[Low prognostic importance of non-radical melanoma excision and the presence of melanoma cells in the re-excision specimen to overall and disease-free survival of melanoma patients]. / Weinig prognostische betekenis van niet-radicale melanoomexcisie en van melanoomcellen in het re-excisiepreparaat voor totale en ziektevrije overleving van melanoompatiënten.

OBJECTIVE: To determine in patients with skin melanoma whether disease-free and overall survival are associated with the tumour excision type and the presence of residual tumour cells in the re-excision specimen. DESIGN: Prospective and descriptive. METHOD: In the period August 1993-August 2004, 471 patients were diagnosed with stage I/II skin melanoma after partial or non-partial removal of a pigmented skin lesion, followed by re-excision and a sentinel node biopsy at Amsterdam Free University Medical Centre, the Netherlands. All patients were followed prospectively with a mean follow-up of > 5 years. Patients were divided into two groups according to (a) the type of primary excision (radical excision, narrow/radical excision, non-radical excision biopsy and incisional biopsy) and (b) the presence or absence of residual tumour cells in their re-excision specimen. Survival analysis was done using Cox proportional hazard model adjusted for the 8 known most important determinants of melanoma. RESULTS: Of the 471 patients, the primary excision was radical in 279 patients and narrow/radical in 109 patients; 52 patients underwent a nonradical excision and 31 patients an incisional biopsy. Re-excision was carried out in 441 patients and in 41 of them residual tumour cells were present in the re-excision specimen. Neither the diagnostic biopsy type nor the presence oftumour cells in the re-excision specimen were connected with disease-free or overall survival in the melanoma patients. CONCLUSION: Non-radical diagnostic biopsies were not negatively associated with overall and disease-free survival in melanoma patients.

[Three patients with a Spitz naevus that later turned out to be a melanoma]. / Drie patiënten met op Spitz-naevus gelijkende afwijkingen die later een melanoom bleken te zijn.

A melanocytic lesion was removed from each of three patients: 2 men aged 37 and 65 and 1 woman aged 45. The preferred diagnosis was 'Spitz naevus'. Subsequently, all three developed regional (sub)cutaneous and/or lymph node metastases, indicating that the lesions were melanomas. The histopathological distinction between Spitz naevus and melanoma is often very difficult. Classical Spitz naevi can be diagnosed correctly only if the entire lesion is available for histological examination. Incompletely removed lesions should be re-excised for further examination. Some melanomas resemble Spitz naevi, but can be recognised on the basis of well-defined histological indicators of malignancy. Some melanocytic lesions, however, cannot be categorised with confidence as being either benign (Spitz naevus) or malignant (spitzoid melanoma). Thus, a group of lesions with inconclusive histology remains and has been designated as 'atypical Spitz tumour' or 'Spitz tumour of uncertain malignant potential'. Generally, such lesions are best treated as melanomas.

Sentinel lymph node investigation in melanoma: detailed analysis of the yield from step sectioning and immunohistochemistry.

AIMS: To evaluate in detail the extent to which step sectioning and immunohistochemical examination of sentinel lymph nodes (SLNs) in patients with melanoma reveal additional node positive patients, to arrive at a sensitive yet workable protocol for histopathological SLN examination. METHODS: The study comprised 29 patients with one or more positive SLN after a successful SLN procedure for clinical stage I/II melanoma. SLNs were lamellated into pieces of approximately 0.5 cm in size. One initial haematoxylin and eosin (H&E) stained central cross section was made for each block. When negative, four step ribbons were cut at intervals of 250 microm. One section from each ribbon was stained with H&E, and one was used for immunohistochemistry (IHC). RESULTS: When taking the cumulative total of detected metastases at level 5 as 100%, the percentage of SLN positive patients increased from 79%, 83%, 83%, 90% to 93% in the H&E sections through levels 1-5, and with IHC these values were 83%, 86%, 90%, 97%, and 100%, respectively. One of six patients in whom metastases were detected at levels 2-5 only had metastases in the subsequent additional lymph node dissection. CONCLUSIONS: Multiple level sectioning of SLNs (five levels at 250 microm intervals) and the use of IHC detects additional metastases up to the last level in melanoma SLNs. Although more levels of sectioning might increase the yield even further, this protocol ensures a reasonable workload for the pathologist with an acceptable sensitivity when compared with the published literature.