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D L Morton

Publications and source records attributed to D L Morton.

At least 19 recordsLinked to original sources
PubMed1992

Variations in the ganglioside profile of uveal melanoma correlate with cytologic heterogeneity.

Gangliosides may play an important role in the proliferation and spread of human malignant melanoma. Because the frequency of metastases in uveal and cutaneous melanoma differs, it is possible that they may express different gangliosides. We analyzed the ganglioside profiles of primary uveal melanoma in 14 cases and of cutaneous melanoma metastasis in 19 cases. In cutaneous melanoma, GM3 ranged from 4.2% to 74.6% and GD3 from 22.1% to 91.8% of total lipid-bound sialic acid. GM2 (found in 13 of 19 cases, ranging from 0.5% to 11.7%), GD2 (11/19, 0.5%-22.0%) and 9-O-acetyl-GD3 (13/19, 0.5%-12.6%) were also frequently observed. By contrast, in 11 cases of uveal melanoma, GM3 was > 90%, GD3 was < 10%, GM2 was < 1.1%; neither GD2 nor 9-O-acetyl-GD3 were detected. The ganglioside profiles of these uveal melanomas were virtually identical to those of normal melanocytes obtained from foreskins. Histological examination of these 11 biopsies showed a monomorphous cell composition, but neither infiltration of lymphocytes or melanophages nor cell necrosis was observed. In 3 other cases, GD3 was increased to 19.5%-46.0%. Histological examination of these 3 biopsy specimens showed at least 2 populations of tumor cells that were separable based on morphological grounds, and mononuclear inflammatory cells interspersed among the tumor cells. An increase in GD3 appears to be related to tumor polyclonality and infiltration of the tumor by lymphocytes and macrophages. These results suggest that ganglioside expression of uveal melanoma is associated with host immune responses to the tumor. Furthermore, the low metastatic capacity of uveal melanoma, in contrast to the high metastatic rate of cutaneous melanoma, may be a result of its differentiated ganglioside expression, which is strikingly similar to that of normal melanocytes.

Gangliosides↗
PubMed1992

Interleukin 4 receptor expression and growth inhibition of gastric carcinoma cells by interleukin 4.

The expression of the interleukin 4 (IL-4) receptor (IL-4R) and effects of human recombinant IL-4 on human gastric carcinoma cell lines were studied. We demonstrated that IL-4 inhibited the growth of gastric carcinoma cells in a dose dependent manner (0.1-100 units/ml) in a [3H]thymidine incorporation proliferation assay. The gastric carcinoma cells varied in sensitivity to treatment with low dose IL-4. Treatment of cells with IL-4 altered the morphology of the cells to a "flattened" morphological shape resembling differentiation. The IL-4-mediated growth inhibition was significantly abrogated by neutralization of IL-4 with specific anti-IL-4 antibody. IL-4R expression on the cell surface was determined by assessing biotin-labeled IL-4 binding to cells using flow cytometry. IL-4R expression ranged from 5 to 85% of total cell population in the gastric carcinoma cell lines assessed. There was a positive correlation between the sensitivity to IL-4-mediated growth inhibition and IL-4R expression. By Northern blot analysis, we demonstrated that mRNA of IL-4R was expressed in the gastric carcinoma cells. Using in situ hybridization, we confirmed that IL-4R mRNA was expressed in the gastric carcinoma cell at the single cell level. By using a sensitive polymerase chain reaction technique, we demonstrated that gastric carcinoma cells expressed IL-4 mRNA, suggesting a possible autocrine loop. These studies indicate that IL-4 can significantly modulate gastric carcinoma cells that possess IL-4R. IL-4R on gastric carcinoma cells may be a potential therapeutic target site for IL-4-directed therapy.

Base Sequence↗
PubMed1992

Technical details of intraoperative lymphatic mapping for early stage melanoma.

The initial route of metastases in most patients with melanoma is via the lymphatics to the regional nodes. However, routine lymphadenectomy for patients with clinical stage I melanoma remains controversial because most of these patients do not have nodal metastases, are unlikely to benefit from the operation, and may suffer troublesome postoperative edema of the limbs. A new procedure was developed using vital dyes that permits intraoperative identification of the sentinel lymph node, the lymph node nearest the site of the primary melanoma, on the direct drainage pathway. The most likely site of early metastases, the sentinel node can be removed for immediate intraoperative study to identify clinically occult melanoma cells. We successfully identified the sentinel node(s) in 194 of 237 lymphatic basins and detected metastases in 40 specimens (21%) on examination of routine hematoxylin-eosin-stained slides (12%) or exclusively in immunohistochemically stained preparations (9%). Metastases were present in 47 (18%) of 259 sentinel nodes, while nonsentinel nodes were the sole site of metastasis in only two of 3079 nodes from 194 lymphadenectomy specimens that had an identifiable sentinel node, a false-negative rate of less than 1%. Thus, this technique identifies, with a high degree of accuracy, patients with early stage melanoma who have nodal metastases and are likely to benefit from radical lymphadenectomy.

Adolescent↗
PubMed1992

Monoclonal antibody-based ELISA to detect glycoprotein tumor-associated-antigen-specific immune complexes in cancer patients.

This report describes the development and applicability of a tumor-associated-antigen-specific immune complex (IC) detection assay to denote the presence of tumor cells in a cancer host. This assay utilizes a murine monoclonal antibody, AD1-40F4, which was produced to a glycoprotein tumor-associated antigen (TAA). In Western blot, the murine monoclonal antibody recognized a 90-100 kD subunit of the antigen. This antigen is immunogenic in cancer patients and induces formation of endogenous antigen-antibody complexes. Analysis of 250 sera from normal individuals and 419 sera from cancer patients revealed that a significantly (P less than .0005) greater proportion (234/419; 55.9%) of cancer sera was positive for the marker than the normal sera (8/250; 3.2%). The incidence of the 90 kD-TAA-specific-IC was consistently and significantly higher in melanoma (58.5%; 38/65), sarcoma (52.9%; 83/157), and carcinoma of breast (50.9%; 58/114), lung (68.2%; 30/44), and colon (64.1%, 25/39) than in the normal group. The age of serum donors did not affect the incidence of the reactivity. Also, at least in the cancer group the gender of the serum donor did not affect the incidence of the 90 kD-TAA-specific-IC positivity. In a retrospective study where sequential serum samples obtained postoperatively from 105 patients with melanoma were analyzed, the 90 kD-TAA-specific-IC could be detected in 72 (69%) of patients several years before the appearance of clinically detectable disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Complement-dependent lysis of tumor cells by a baboon IgM antibody to a tumor-associated antigen.

We developed a high-titer polyclonal antiserum to a glycoprotein tumor-associated antigen (TAA) by immunization of a baboon with the purified glycoprotein antigen. The baboon serum was fractionated into IgG and IgM components by DEAE Affi-Gel blue chromatography. The ability of the baboon IgM anti-TAA antibody to effect tumor cell lysis in the presence of complement was tested using a chromium-release assay. The baboon antibody was able to lyse melanoma target cells (20.8%-71.4% cytolysis), breast carcinoma cells (36.5%-38.9% cytolysis), and a neuroblastoma cell line (35.5% cytolysis) in the presence of complement but did not effect significant lysis of autologous lymphoblastoid cell lines (4.9% cytolysis) or peripheral blood lymphocytes from healthy volunteers (12.6% cytolysis). Cytolysis of melanoma target cells was completely inhibited by preabsorption of the IgM anti-TAA antibody with UCLA-SO-M14 (M14) cells and partially inhibited by preabsorption with several other melanoma cell lines. There was no significant inhibition of tumor cell lysis after preabsorption of the antibody with lymphoblastoid cell lines. Complement-dependent lysis of M14 targets could be blocked by addition of the purified antigen to the antibody prior to incubation with the tumor cells. Our results suggest that the glycoprotein TAA resides on the tumor cell surface and that the baboon IgM anti-TAA antibody recognizes the antigen on the cell surface and is able to fix complement and effect the lysis of the tumor cells.

Animals↗
PubMed1992

Cytotoxic T cell lines recognize autologous and allogeneic melanomas with shared or cross-reactive HLA-A.

Cytotoxic T lymphocytes (CTL), CD3+, alpha/beta T-cell-receptor-positive, are important effector cells with specific immunity in melanoma patients. The establishment and expansion in vitro of CTL of a specific phenotype to tumor cells strongly depends on the method of activation and sensitization with tumor cells. We generated CD3+ CTL lines to melanoma by co-culturing peripheral blood lymphocytes with autologous irradiated melanoma cells and repetitive stimulation with high-dose interleukin-4 in a "cocktail" culture medium. CTL lines were investigated for their specificity to kill autologous and allogeneic melanoma. Histocompatibility locus antigen (HLA) class I (A, B) molecules are important restrictive recognition antigens for CTL. Although these antigens are highly polymorphic, they can share a similar immunogenic molecular epitope(s) and can be immunologically cross-reactive. The CTL lines generated were found to kill not only autologous melanoma, but also allogeneic melanomas having class I HLA-A antigens shared or "cross-reactive" with autologous HLA-A. These CTL lines were poor killers of melanomas bearing non-shared or non-cross-reactive HLA-A. Cold-target inhibition assays demonstrated this CTL cross-reactivity to allogeneic melanoma specificity. Epstein-Barr-virus-transformed autologous and allogeneic B lymphoblastoid cell lines failed to block autologous melanoma killing, indicating that CTL were not recognizing major histocompatibility complex antigens, serum proteins or culture medium products as the primary target antigen. HLA-A2 was the major shared HLA-A antigen recognized by CTL lines on the melanoma lines studied. CTL lines also recognized shared HLA-A11 and A24 on allogeneic melanoma. There were no CTL lines showing restriction to HLA-B. These results suggest that common tumor-associated antigens are present on melanomas and are recognized in association with distinct HLA-A epitopes by CTL.

Antigens, Neoplasm↗
PubMed1992

Induction of CD4+ cytotoxic T cells by sensitization with allogeneic melanomas bearing shared or cross-reactive HLA-A.

Human melanoma is an immunogenic neoplasm whereby enhancement of specific cell-mediated immunity can alter tumor progression. HLA-A2-restricted CTL have been demonstrated to kill allogeneic HLA-A2-matched melanoma. We investigated the ability of allogeneic melanoma cells sharing HLA-A antigens to sensitize melanoma patients' lymphocytes to induce HLA-A-restricted CTL to autologous melanoma. PBL from melanoma patients were cocultured with autologous melanoma cells in defined "cocktail medium" to generate melanoma-specific HLA-A-restricted CTL lines. CTL generated by sensitization with allogeneic melanoma bearing shared HLA-A2, A11, A24, or "cross-reactive" HLA-A antigens could kill almost as many autologous melanoma cells as CTL sensitized with autologous melanoma. There are HLA-A antigens that are immunogenically cross-reactive because they share determinant epitopes. CTL were not activated NK or LAK cells. The HLA restriction and melanoma cell specificity of the CTL were demonstrated by cold target inhibition with autologous and allogeneic melanoma and B lymphoblasts. Anti-CD3 and anti-HLA AB inhibited CTL killing of melanoma. The CTL were predominantly CD3+CD4+ TCR alpha/beta+. These studies demonstrate that melanomas being shared or cross-reactive HLA-A can be used for in vitro generation of HLA-restricted CTL that recognize melanoma-associated antigens. The findings have very important implications in human tumor immunotherapy.

CD4 Antigens↗
PubMed1992

Prolongation of survival in metastatic melanoma after active specific immunotherapy with a new polyvalent melanoma vaccine.

A new polyvalent melanoma cell vaccine (MCV) was administered to 136 stage IIIA and IV (American Joint Committee on Cancer) melanoma patients. Induction of cell-mediated and humoral immune responses to common melanoma-associated antigens present on autologous melanoma cells was observed in patients receiving the new MCV. This was accompanied by increased activation of tumor-infiltrating lymphocytes. Survival correlated significantly with delayed cutaneous hypersensitivity (p = 0.0066) and antibody responses to MCV (p = 0.0117). Of 40 patients with evaluable disease, nine (23%) had regressions (three complete). From our historical database of 126 stage IIIA and 1275 stage IV melanoma patients, there were no significant changes in the natural history of metastatic melanoma during the past 20 years. Univariate and multivariate analyses demonstrated prognostic significance for site of metastases (p = 0.0001) and immunotherapy with the new MCV (p = 0.0001). Overall our new MCV increased the median and 5-year survival of stage IIIA melanoma patients with regional soft tissue metastases twofold (p = 0.00024), and stage IV patients threefold (p = 0.0001) compared with previous immunotherapy and other treatments.

Adult↗
PubMed1992

Ganglioside GM2 levels in human melanoma cells: inverse correlation with lysosomal beta-hexosaminidase A activity.

GM2 is usually significantly elevated in human melanoma cells. The lysosomal hydrolase beta-hexosaminidase A (Hex A), is an isoenzyme required for terminal GalNAc hydrolysis from intact GM2 to GM3. The objective of the present studies is to determine if the elevated levels of gangliosides, particularly GM2, correlate with the activity of Hex A in cultured melanoma cells. The Hex A activity in 13 melanoma cell lines ranged from 26%-88.3% There was a inverse correlation between GM2 nmole/g and Hex A activity (r = -0.48; p less than 0.003). An inverse correlation (p less than 0.03) occurred between GD2 nmole/g and Hex A activity. There was an inverse correlation (r = -0.53; p less than 0.05 and r = -0.51; p less than 0.05, respectively) between the ratio of substrate/product (GM2/GM3) and (GD2/GD3) and Hex A activity. These results indicate that the level of GM2 in melanoma is inversely correlated with the level of activity of Hex A.

Analysis of Variance↗
PubMed1992

Interleukin-6 production by human melanoma cell lines.

We examined the expression of interleukin-6 (IL-6) by 12 established human melanoma cell lines. Two constitutively produced low levels of IL-6 protein, as measured by enzyme-linked immunosorbent assay. Cells from these two lines, as well as those from two non-IL-6-producing cell lines, contained IL-6-specific mRNA as demonstrated by Northern hybridization. Treatment of the two IL-6-producing melanoma cell lines with interleukin-1 beta, tumor necrosis factor-alpha, or phorbol myristate acetate caused a marked increase in IL-6 production. These induction signals failed to stimulate IL-6 production in the nonproducing cells, even those that expressed IL-6 mRNA. IL-6 did not appear to act as an autocrine growth factor since the addition of exogenous human recombinant IL-6 or polyclonal anti-IL-6 antibody did not alter cellular proliferation. The production of this multifunctional cytokine by tumors may play a role in tumor-host interactions and this should be recognized in the design of biologic therapy trials.

Blotting, Northern↗
PubMed1991

Interleukin 4 alone and with gamma-interferon or alpha-tumor necrosis factor inhibits cell growth and modulates cell surface antigens on human renal cell carcinomas.

Immune cytokines have been shown to play important roles in regulating immune cell functions as well as neoplastic cells. Interleukin-4 (IL4), primarily known as a B-cell growth factor, can also activate and differentiate other immune cells. This cytokine has recently been shown to have immunotherapeutic benefit in tumor-bearing hosts. The present study assessed the effect on human renal cell carcinoma cell lines of recombinant IL4 alone and in combination with recombinant gamma-interferon (IFN) or recombinant alpha-tumor necrosis factor (TNF). IL4 inhibited cell growth of all lines at 250-500 units/ml in a differential manner. Expression of IL4 receptors was demonstrated on renal cell carcinomas. Overall, IFN (500 units/ml) alone inhibited cell growth; however, TNF (500 units/ml) was not as strong an inhibitor. When IL4 was combined with IFN or TNF there was a significant augmentation of cell growth inhibition and modulation of cell morphology of the cell lines. Tumor-associated ganglioside antigens (NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer, NeuAc alpha 2-8NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer, GalNAc beta 1-4 (NeuAc alpha 2-3)Gal beta 1-4Glc beta 1-1'Cer, and GalNAc beta 1-4(NeuAc alpha 2-8NeuAc alpha 2-3)Gal beta 1-4Glc beta 1-1'Cer) HLA class I, HLA-DR, and beta 2-microglobulin on the cell surface of renal cancer lines were assessed by flow cytometry and radiometric binding assay. IL4 alone or in combination with other cytokines modulated HLA class I and HLA-DR expression. IL4 and IFN consistently enhanced NeuAc alpha 2-8NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer and GalNAc beta 1-4(NeuAc alpha 2-8NeuAc alpha 2-3)Gal beta 1-4Glc beta 1-1'Cer expression on individual cell lines. The study demonstrated that IL4 alone or in combination with other cytokines can significantly inhibit growth, and modulate the expression of surface major histocompatibility and tumor-associated antigens of renal cell carcinomas.

Carcinoma, Renal Cell↗
PubMed1991

Ganglioside GM3:GD3 ratio as an index for the management of melanoma.

This report evaluates the relevance of the ratio of the melanoma-associated ganglioside, GD3, and its precursor, GM3, to prognosis and management of Stage II disease. Tumor biopsy specimens from 42 melanoma patients were examined for the ratio and found that GD3 and GM3 constitute 80% of the total lipid bound sialic acids (LBSA) of melanoma. Although the ratio of GM3:GD3 in melanocytes, the progenitors of melanoma, is 19:1 (based on %LBSA), it ranged from 15:1 to 1:5 in tumor biopsy specimens. Patients are categorized into three groups based on their GM3:GD3 ratio (%LBSA) of tumor tissues as Group I (ratio ranged from 15:1 to 1.5:1) (10 of 42), Group II (1.4:1 to 1:1.4) (13 of 42), and Group III (1:1.5 to 1:5) (19 of 42). When the overall survival of patients from the onset of Stage II disease was evaluated among different groups, patients belonging to Group I survived significantly longer than patients of Group II (P = 0.02) and Group III (P = 0.01). Interestingly, Group III expressed immunogenic gangliosides (GD2, GM2, and O-AcGD3) better than the other groups and may benefit more from therapies targeted against these gangliosides antigens. The results of this study indicate that GM3:GD3 ratio is an unusual but well-defined biochemical criteria that may be useful for prognosis and therapeutic management of the disease. Therefore, we propose a routine analysis of the GM3:GD3 ratio of tumors excised after surgery. Screening the ratio is feasible since melanoma expresses a simple profile of gangliosides unlike other forms of cancer.

Adolescent↗
PubMed1991

Modulation of human melanoma cells by interleukin-4 and in combination with gamma-interferon or alpha-tumor necrosis factor.

Immune cytokines have been shown to play important roles in regulating immune cell functions. Interleukin-4 (IL4), originally described as a B-cell growth factor, is known to activate and differentiate other immune cells. IL4 has been given as an immunotherapeutic to tumor-bearing hosts. In this report, we set out to determine whether IL4 can directly modulate growth and expression of surface antigens on human melanoma cells. The effect of recombinant IL4 alone and in combination with recombinant gamma-interferon (IFN) or recombinant alpha-tumor necrosis factor (TNF) on melanoma cell lines was examined. IL4 significantly inhibited cell growth of all cell lines examined at 100-500 units/ml; but a dose-dependent differential response to individual cell lines occurred. The effect of IL4 was augmented by combination with IFN or TNF. Melanoma-associated ganglioside antigens (GM3, GD3, GM2, GD2) and human leukocyte antigen class I and DR on the cell surface of melanoma cells were assessed by flow cytometry and/or a radiometric binding assay. IL4, IFN, or TNF alone enhanced human leukocyte antigen class I, DR, and beta 2-microglobulin antigen expression. IL4 alone and in combination with IFN or TNF increased the GM3/GD3 ratio expression. GD2 was enhanced significantly by IL4, IFN, and TNF. Pretreatment of melanoma with IL4 or with other cytokines prior to stimulation with peripheral blood lymphocytes significantly enhanced mixed lymphocyte tumor reaction activity as compared with non-treated melanoma used as stimulators. These studies demonstrate that IL4 alone or in combination with IFN and TNF can modulate melanoma growth activity and surface antigen expression to a more differentiated and immunogenic phenotype.

Antigens, Neoplasm↗
PubMed1991

The importance of anatomic site in prognosis in patients with cutaneous melanoma.

To determine the prognostic relevance of the anatomic site of origin of cutaneous melanoma to survival, we retrospectively analyzed a computerized database of 3428 patients with stage I and II cutaneous melanoma. Patients were stratified by the recognized prognostic variables of stage of disease, Clark's level of invasion of the primary lesion, and the nodal involvement at the time of lymphadenectomy. Melanoma arising in skin of the upper part of the back, back of the arms, neck, and scalp (BANS) region occurred more frequently in male than female patients. There were no statistically significant differences in the distribution of Clark's level of invasion of BANS and non-BANS region primary melanomas or in the extent of nodal involvement in patients with stage II disease. The 5-year actuarial survival of patients with stage I BANS region melanomas was 87%; stage I non-BANS, 89%; stage II BANS, 38%; and stage II non-BANS, 69%. The BANS region appears to have prognostic significance in cutaneous melanoma and, particularly, in patients with stage II melanoma.

Actuarial Analysis↗
PubMed1991

Prospective evaluation of the use of antigen-specific immune complexes in predicting the development of recurrent melanoma.

We previously demonstrated that the antigen-specific immune complexes captured by the monoclonal antibody MAb JSI in a sandwich enzyme-linked immunosorbent assay were associated with recurrent melanoma. To determine the potential use of antigen-specific immune complex analysis in predicting the development of recurrent melanoma, we prospectively analyzed serum obtained from patients with melanoma following surgical treatment. Two hundred fifty-three patients have been followed up for a median of 25 months (range, 17 to 29 months). Seventy-seven patients (30%) have developed recurrent melanoma. Antigen-specific immune complexes correlated with the stage of disease at time of entry into the study. The absence of antigen-specific immune complexes in postoperative serum samples is predictive of a disease-free status. Long-term follow-up will define the false-positive rate of antigen-specific immune complex analysis. Continued refinement of this approach should lead to clinically useful methodology to monitor human melanoma.

Antibodies, Monoclonal↗
PubMed1991

Production of tumor necrosis factor alpha and interferon gamma in interleukin-2-treated melanoma patients: correlation with clinical toxicity.

Interleukin-2 (IL-2)-based immunotherapy regimens are accompanied by dose-limiting toxicity consisting of fever, tachycardia, chills and capillary leak syndrome. We hypothesized that the toxicity was caused by the induction and release of endogenous cytokines such as tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma). We measured the serum levels of TNF alpha and IFN gamma in IL-2-treated melanoma patients and attempted a correlation with clinical toxicity. A total of 23 patients received either 6 x 10(6) IU or 12 x 10(6) IU Cetus IL-2/m2 by i.v. bolus daily for 5 consecutive days on weeks 1, 3 and 5. Serum TNF alpha and IFN gamma levels were measured by enzyme-linked immunosorbent assay. Clinical toxicity was scored each day by objective measurements of hypotension, tachycardia, fever and chills/rigors. Clinical toxicity and IFN gamma levels correlated nicely, peaking on the 5th day of each treatment cycle. The kinetics and magnitude of TNF alpha production, however, were not predictable and did not correlate with either IFN gamma or toxicity. Some patients had modest increases in TNF alpha production while others had markedly increased levels during the second and third treatment weeks. Remarkably, these high levels persisted during nontreatment weeks and after completion of therapy. This clinical study demonstrates novel kinetics for immunoreactive TNF alpha in IL-2 cancer patients, which do not correlate well with toxicity.

Humans↗
PubMed1991

Role of percutaneous fine-needle aspiration biopsy in suspected intrathoracic malignancy.

Percutaneous fine-needle aspiration (PFNA) biopsy is an accepted technique for the diagnosis of suspected intrathoracic malignancy, but the appropriate indications for its use have not been clearly defined. To help establish guidelines, we performed a retrospective analysis of 188 patients who underwent PFNA biopsy for suspected intrathoracic malignancy. Biopsy led to a diagnosis in 72% (135/188) of the patients, but in 27% (50/188) samples were inadequate for cytological diagnosis, and in 2% (3/188) samples were adequate but failed to yield a diagnosis. Fifty-three patients underwent surgical intervention, thus allowing histological confirmation of the cytological diagnosis. In patients with a diagnosis from PFNA biopsy, operation confirmed malignancy in 97% (37/38) and a specific cell type in 79% (30/38). In patients without a diagnosis after biopsy, a malignancy was found in 73% (11/15) at the time of operation. This suggests a high rate of accuracy when PFNA biopsy provides a diagnosis. However, it also illustrates that a substantial percentage of PFNA biopsy attempts fail to yield a diagnosis in patients ultimately found to have malignancies. This implies that PFNA biopsy might best be reserved for patients who are not surgical candidates.

Adenocarcinoma↗