title: Spectrum of morphologic alterations of regression in cutaneous melanoma--potential for improving disease prognosis.
abstract: BACKGROUND
  Regression occurs as a complex interaction between tumor cells and host's immune response; neither biologic mechanisms, nor regression prognostic significance are deciphered to date but promising anti-cancer vaccine strategies were thus developed.
  
  
  METHODS
  We analyzed 127 superficial spreading melanomas identifying melanoma with regression (segmentary (SR), partial (PR) and segmentary & partial (SR-PR)) or without regression (AR). Several histopathologic parameters were registered; statistical analysis was performed (level of significance P < 0.05).
  
  
  RESULTS
  Regression was present in 52% cases, less frequently in pT4 melanomas. Ulceration and vascular invasion were similarly present in pT2-pT4 melanomas with regression and significantly less in pT1 ones; their incidence increased with stage in AR (P < 0.001). SR and SR-PR melanomas showed significantly more tumor infiltrating lymphocytes within the non-regressed tumor than AR melanomas (P < 0.05). SR melanomas presented significantly less frequent mitoses than PR (P = 0.04), SR-PR (P = 0.04) or AR ones (P = 0.03). Marked inflammation and more numerous melanophages were present regressed areas advanced stage melanomas. More numerous plasma cells were identified in advanced stages; in SR and SR-PR melanomas less numerous plasma cells were present in pT1 than in advanced stages. Vascular hyperplasia was significantly higher in SR than SR-PR cases.
  
  
  CONCLUSIONS
  Differences in perception of regression might be the result of labeling with similar name of various processes comprising inflammation and tumor cells destruction; at least in thin melanomas, PR and SR seem to belong to different spectrum of alteration, SR bearing a more favorable potential. Further studies will be performed in order to further elucidate the mechanisms involved in regression in melanoma.
authors: "Colentina" University Hospital, Dept. of Pathology, Bucharest, Romania. sabina_zurac@yahoo.com
authors: Sabina
authors: S
authors: Zurac
authors: Gabriela
authors: G
authors: Negroiu
authors: Stefana
authors: S
authors: Petrescu
authors: R
authors: R
authors: Andrei
authors: T
authors: T
authors: Tebeica
authors: Cristiana
authors: C
authors: Popp
authors: Roxana
authors: R
authors: Musţată
authors: Monica
authors: M
authors: Neagu
authors: Carolina
authors: C
authors: Constantin
authors: C
authors: C
authors: Solovan
authors: Virginia
authors: V
authors: Chiţu
authors: A
authors: A
authors: Reboşapcă
authors: B
authors: B
authors: Andreescu
authors: I
authors: I
authors: Marinescu
authors: Florica
authors: F
authors: Stăniceanu
mesh_terms: D006801:Humans; D008545:Melanoma / Q000473:pathology*; D008940:Mitotic Index; D009361:Neoplasm Invasiveness; D009365:Neoplasm Regression, Spontaneous / Q000473:pathology* / Q000503:physiopathology; D011379:Prognosis; D012871:Skin Diseases / Q000473:pathology*