Impact of Dermoscopy and Reflectance Confocal Microscopy on the Histopathologic Diagnosis of Lentigo Maligna/Lentigo Maligna Melanoma

BACKGROUND

Equivocal pigmented lesions of the head are usually biopsied to avoid inappropriate treatment. Clinical approach has evolved from simple visual examination to sophisticated techniques for selecting the biopsy sites.

OBJECTIVE

This study aimed to retrospectively evaluate the efficiency of dermoscopy (DE) and reflectance confocal microscopy (RCM) in sampling a histopathologically representative focus of lentigo maligna/lentigo maligna melanoma.

METHODS

Punch biopsies and surgical excisions of 72 patients, 37 men and 35 women (median age 70.6 years, range 39-90 years), affected by lentigo maligna/lentigo maligna melanoma of the head, sent from a single dermatology clinic, were reviewed for the presence of 5 histopathologic criteria: atypical junctional melanocytes, increased junctional melanocytes, follicular colonization, pagetoid spread and melanocytic junctional nests, plus other minor features. Forty-two patients were biopsied under DE and 30 under RCM guidance.

RESULTS

Accuracy of the 2 techniques in sampling a representative tissue overlapped in most cases, although RCM selected sites to biopsy with more histopathologic criteria, in particular pagetoid spread and melanocytic nests. Interestingly, with RCM, inflammation and melanophages were observed more in biopsy than in excision. False positive cases were not registered.

CONCLUSION

Compared with the sampling at naked eye, our results show that DE and RCM help selecting the most appropriate areas for biopsies, thus allowing not only more robust histopathologic diagnoses, but also a more accurate microstaging of tumor.

Vanishing tumors of thyroid: histological variations after fine needle aspiration

BACKGROUND

Fine needle aspiration (FNA) can lead to changes that extensively replace cytological confirmed thyroid lesions. These lesions, so called "vanishing tumors" can be diagnostically challenging to pathologists and therapeutically challenging for endocrinologists and surgeons. We performed a retrospective analysis to identify these tumors.

METHODS

Data of 656 patients referred for thyroid surgery was reviewed. Patients with suspicious lesions on neck ultrasound (US) underwent FNA. We compared FNA cytological and surgical pathological findings to identify vanishing tumors. FNA-induced changes such as cystic degeneration, hemorrhage, calcification, cholesterol crystals, fibrosis and granulation tissue were identified.

RESULTS

Seventeen patients (2.5%) were identified with vanishing tumors. FNA cytology was indeterminate in seven (41.1%) and benign in ten (58.8%) patients. Surgical pathology in all nodules showed regressive changes partially or entirely replacing the tumor. The mean size of vanishing tumors was 2.4±1.5 cm in greatest dimension. Seven nodules (41.1%) were entirely replaced while remaining ten nodules showed partial replacement of tumors. Three (17.6%) nodules had focal areas of optically clear nuclei suspicious of papillary thyroid carcinoma (PTC); one showed an additional focus of follicular neoplasm (FN) of uncertain malignant potential.

CONCLUSIONS

FNA-induced changes can lead to obliteration of nodules rendering pathological diagnosis with no evidence of confirmed lesions. Pathologists and surgeons should be aware of this challenging scenario.

Trends in prostatic adenocarcinoma tumor volume by visual estimation in prostatectomy specimens

We retrospectively reviewed 1792 consecutive radical prostatectomies (RP) from 2003 to 2006 at a single institution to establish tumor volume reference values, to determine current trends in visually estimated prostate adenocarcinoma tumor volume, and to characterize cases with no residual cancer on RP. Tumor volumes were recorded and subsequently stratified as very low, 0-1%; low, 1.1-10%; intermediate, 10.1-20%; high, 20.1-50%; and very high, >50%, with incidences of 11.7%, 52.1%, 21.5%, 13.2%, and 1.5%, respectively. The incidence of very low volume tumors increased within the time period (p=0.04). Seminal vesicle involvement was detected in 5.0% of cases and lymph node metastasis occurred in 1.4%. Volume categories statistically correlated with seminal vesicle invasion (p=0) and lymph nodes metastases (p=0). Eleven cases of no residual cancer (0.6%) were identified with a non-statically significant increase during the study (p=0.07). The rising incidence of very low volume tumors should be considered by clinicians when discussing treatment options with patients. A discrete tumor volume should be provided for RP specimens as it may be an important prognostic factor.