Unknown primary adenocarcinoma: incidence of overinvestigation and natural history

Positive factors on survival of head and neck cancer of unknown primary: what the clinician can do

BACKGROUND

Management of patients with head and neck cancer of unknown primary (HNCUP) is challenging.

AIMS/OBJECTIVES

To provide a long-term analysis focusing on protective survival factors for clinical decision-making. Furthermore, the prognostic value of the current N classification system was evaluated.

MATERIAL AND METHODS

We retrospectively analyzed patients with HNCUP between 2003 and 2016. Univariate and multivariate analyses were used to investigate predictors of overall survival (OS).

RESULTS

A primary tumor was found in 67 of 290 patients with suspected HNCUP, leaving after exclusion 141 HNCUP cases for analysis, who received multi-step therapy (MST) (n = 108) or single therapy (n = 28). Chemotherapy (CT) (n = 101), curative MST, ≤3 positive lymph nodes (LN) (n = 33), squamous cell carcinoma (SCC) (n = 123), HPV+ (n = 21), M0 (n = 70) increased OS by 21.8%, 24.4%, 12.7%, 6.8%, 18.7%, 29.6%, respectively. 5- and 10-year OS was 78.1%/66.6%. The number of metastatic LNs predicted OS is better than N classification.

CONCLUSION AND SIGNIFICANCE

Aspects for clinical decision-making: Curative MST and SCC histology were the most significant predictors for improved OS. Categorizing LN into 1, 2-3, and >3 LNs was more significant than the traditional N classification. The addition of CT to curative MST has a stronger impact on survival than HPV and N classifications.

Cancer of Unknown Primary: Challenges and Progress in Clinical Management

Simple Summary

Patients with cancer of unknown primary site suffer the burden of an uncertain disease, which is characterized by the impossibility to identify the tissue where the tumor has originated. The identification of the primary site of a tumor is of great importance for the patient to have access to site-specific treatments and be enrolled in clinical trials. Therefore, patients with cancer of unknown primary have reduced therapeutic opportunities and poor prognosis. Advancements have been made in the molecular characterization of this tumor, which could be used to infer the tumor site-of-origin and thus broaden the diagnostic outcome. Moreover, we describe here the novel therapeutic opportunities that are based on the genetic and immunophenotypic characterization of the tumor, and thus independent from the tumor type, which could provide most benefit to patients with cancer of unknown primary.

Abstract

Distant metastases are the main cause of cancer-related deaths in patients with advanced tumors. A standard diagnostic workup usually contains the identification of the tissue-of-origin of metastatic tumors, although under certain circumstances, it remains elusive. This disease setting is defined as cancer of unknown primary (CUP). Accounting for approximately 3–5% of all cancer diagnoses, CUPs are characterized by an aggressive clinical behavior and represent a real therapeutic challenge. The lack of determination of a tissue of origin precludes CUP patients from specific evidence-based therapeutic options or access to clinical trial, which significantly impacts their life expectancy. In the era of precision medicine, it is essential to characterize CUP molecular features, including the expression profile of non-coding RNAs, to improve our understanding of CUP biology and identify novel therapeutic strategies. This review article sheds light on this enigmatic disease by summarizing the current knowledge on CUPs focusing on recent discoveries and emerging diagnostic strategies.

Does Cancer of Unknown Primary (CUP) Truly Exist as a Distinct Cancer Entity?

Cancer of unknown primary (CUP) designates an enigmatic cancer entity with histologic confirmation of malignancy from a metastasis but no identifiable primary tumor in spite of a thorough diagnostic work-up. In this review, we discuss the validity of CUP as a distinct cancer entity as well as diagnostic pitfalls. As arguments against a distinct entity, the diagnosis of CUP is erroneous in some cases. Diagnostic pitfalls include incomplete diagnostics, uncertainty in classifying a lesion as either primary or metastasis and mistaking a relapse of an antecedent malignancy as CUP due to histologic and immunohistologic disparities. Given the high frequency of prior malignancies in CUP patients, relapse of an antecedent cancer should always be carefully excluded. Gene expression profiling-based classifier assays aim at aligning the molecular profile of CUP patients with established primary cancer patterns for highest congruency in order to identify the putative primary and treat accordingly. However, the spectrum of predicted putative primaries by molecular techniques is somewhat at odds with the primaries identified in autopsy series. Also, a first randomized clinical trial did not show superiority of primary-tailored therapy over unspecific platinum-based chemotherapy. CUP cases share an aggressive clinical course, atypical metastasis pattern, rapid progression of metastases, a generally poor response to chemotherapy and dismal outcome as distinct clinical features. Metastatic spread appears to take place in the early stages of tumor evolution, with CUP metastases subsequently undergoing genetic evolution toward a chromosomally highly complex and instable karyotype independent from the primary tumor. In clinical practice, the diagnosis of CUP is valid when no primary tumor is detectable. Treatment should ideally offer broad spectrum coverage across numerous malignancies and be well-established in CUP as is the case for carboplatin/paclitaxel and cisplatin / gemcitabine in particular, but it should also cover the most likely putative primary. The diligent diagnosis of CUP is warranted for clinical trials, making the eligibility process particularly laborious. In conclusion, we deem CUP a distinct cancer entity and the diagnosis accurate in most patient cases.

Adenocarcinoma of Unknown Primary Site with Bone Marrow and Orbital Metastases Suggestive of a Prostatic Origin

Prostate cancer may occasionally present as an adenocarcinoma with an undetermined primary site. We report a case in which bone marrow invasion and orbital metastasis were the first evidence of malignancy. Recognition of metastatic prostate cancer is important since it can be managed safely and effectively with hormonal therapy.

Diagnostic Interest of the Monoclonal Antibody Ca1 in Malignant Pleural Effusion

The Ca1 antibody was used in an immunohistochemical procedure on smears of cells from 40 patients with malignant pleural effusion. The control group consisted of 25 benign pleural effusions with a high percentage of reactive mesothelial cells. The Ca1 Me Ab was positive in 19 (79%) of the 24 pleural effusions with positive malignant cytology. In all the benign cases the Ca1 Mc Ab was negative (100% specificity). The Ca1 Mc Ab detected malignant mesothelial cells in two cases and was negative with reactive mesothelial cells and other nucleated cells present in the pleural effusion. We conclude that the Ca1 antibody offers a useful diagnostic method for malignant pleural effusions, when the morphological interpretation is doubtful.

Perceptions of cancer of unknown primary site: a national survey of Australian medical oncologists

BACKGROUND

Despite being the sixth most common cause of cancer death in Australia, cancer of unknown primary (CUP) site remains poorly understood.

AIMS

To describe practices relating to the diagnosis, investigation, classification, communication and management of CUP among medical oncologists.

METHODS

We invited all members of the Medical Oncology Group of Australia to participate in a national, anonymous online survey about CUP. The survey collected data regarding diagnosis acceptance, diagnostic tests, treatment protocols and communication practices around the diagnosis of CUP.

RESULTS

Three hundred and two oncologists were invited and 86 (28%) completed the survey. Eighty (93%) respondents were directly involved in the assessment of patients with CUP. Eighty-five (99%) respondents were prepared to make a diagnosis of CUP if, after appropriate diagnostic tests, the primary location could not be ascertained. Eighty-three percent would assign a primary site to obtain Pharmaceutical Benefits Schedule funding of medical therapy. Sixty-two percent did not have a specific treatment protocol designed for CUP. The majority of oncologists used serum tumour markers and computed tomography scans in the initial work-up, while 43% indicated they would use a positron emission tomography scan in the majority of cases. The majority would arrange mammography in female patients. Thematic analysis of responses to open-ended questions about how CUP is described identified little consistency in the language being used.

CONCLUSION

The approach to diagnosis, investigation and management of CUP by medical oncologists in Australia is variable. Many preferred to estimate the primary site and treat accordingly. Pharmaceutical Benefits Schedule restrictions may encourage the practice of 'best guessing'.

Precision medicine based on epigenomics: the paradigm of carcinoma of unknown primary

Epigenetic alterations are a common hallmark of human cancer. Single epigenetic markers are starting to be incorporated into clinical practice; however, the translational use of these biomarkers has not been validated at the 'omics' level. The identification of the tissue of origin in patients with cancer of unknown primary (CUP) is an example of how epigenomics can be incorporated in clinical settings, addressing an unmet need in the diagnostic and clinical management of these patients. Despite the great diagnostic advances made in the past decade, the use of traditional diagnostic procedures only enables the tissue of origin to be determined in ∼30% of patients with CUP. Thus, development of molecularly guided diagnostic strategies has emerged to complement traditional procedures, thereby improving the clinical management of patients with CUP. In this Review, we present the latest data on strategies using epigenetics and other molecular biomarkers to guide therapeutic decisions involving patients with CUP, and we highlight areas warranting further research to engage the medical community in this unmet need.

Unknown primary adenocarcinomas: a single-center experience

This study aimed to elucidate the clinical and prognostic characteristics of a homogeneous group of patients with cancer of unknown primary (CUP). Between 1999 and 2014, CUP was diagnosed in 159 (1.3%) of 11,742 cancer patients at Trakya University Hospital (Edirne, Turkey). Ninety-seven (61%) of the 159 patients were retrospectively reviewed. Among these, 61 (62.8%) patients with adenocarcinoma were included in this study. The most frequently predicted primary tumor site was the lung (37.7%), and 59% of the patients were smokers. There was a significant relationship between smoking and the lung as a potential primary cancer site (p = 0.042). The most frequent site of metastasis was the liver (60.7%). The median number of metastases per patient was two, but patients with liver metastases had a median of five metastases. The overall median survival time was 7 months. Median survival was significantly longer in patients with a predicted primary site than in patients without the predicted site (7 vs. 6 months, respectively; p = 0.038). When the patients with predicted ovarian and peritoneal tumors were excluded from the comparison, the statistical p value was still close to significant (p = 0.07). Multivariate analysis revealed that smoking, liver metastasis, serum alkaline phosphatase ≥92 U/L, and progression in response to chemotherapy were independent predictors of a poor prognosis. The present study identified several independent prognostic factors in patients with unknown primary adenocarcinomas who received chemotherapy. Smoking, the presence of liver metastasis, and response to chemotherapy were independent risk factors for both progression-free and overall survival.

Squamous cell carcinoma causing dorsal atlantoaxial spinal cord compression in a dog

A 12-year-old Chihuahua dog was presented for cervical pain and progressive tetraparesis. Magnetic resonance imaging revealed spinal cord compression due to a mass in the dorsal atlantoaxial region. Surgical treatment was performed. The mass was histopathologically diagnosed as a squamous cell carcinoma. The dog recovered to normal neurologic status after surgery.

Skeletal Metastasis of Unknown Primary Origin at the Initial Visit: A Retrospective Analysis of 286 Cases

Background

Skeletal metastasis is a common metastatic event for several carcinomas, and the treatment for skeletal metastasis of unknown primary (SMUP) are a critical issue in cancer therapy. Making a diagnosis of the primary site is the most crucial step in the treatment of SMUP; however, the procedures are sometimes difficult and time-consuming, and the primary site often remains unknown. Therefore, to establish optimal diagnostic strategies and elucidate the overall survival rates of SMUP, we conducted this retrospective study.

Methods

We retrospectively analyzed the clinical data for 286 SMUP cases from a total of 2,641 patients with skeletal metastases who were treated between 2002 and 2014 at our initiations.

Results

The primary sites were identified in 254/286 patients (88.8%), while 32 (11.2%) primary sites were not detected by our diagnostic strategies. Lung cancer was identified in 72 (25.2%) cases, and was the most frequently observed primary lesion. The median survival time of the SMUP patients was 20.0 months, while the median survival times of solitary bone metastasis cases and multi-bone metastasis cases were 39.0 months and 16.0 months, respectively. The median survival times of prostate cancer cases was over 120 months, that of patients with primary lung cancers was 9.0 months and the median survival time of cases who were finally diagnosed with an unknown primary was 11.0 months.

Conclusions

We believe that our study would contribute to establishing an optimal strategy for diagnosing the primary site in SMUP patients, and our data provide definite indications for the survival times for different SMUP situations.

RNA-Seq accurately identifies cancer biomarker signatures to distinguish tissue of origin

Metastatic cancer of unknown primary (CUP) accounts for up to 5% of all new cancer cases, with a 5-year survival rate of only 10%. Accurate identification of tissue of origin would allow for directed, personalized therapies to improve clinical outcomes. Our objective was to use transcriptome sequencing (RNA-Seq) to identify lineage-specific biomarker signatures for the cancer types that most commonly metastasize as CUP (colorectum, kidney, liver, lung, ovary, pancreas, prostate, and stomach). RNA-Seq data of 17,471 transcripts from a total of 3,244 cancer samples across 26 different tissue types were compiled from in-house sequencing data and publically available International Cancer Genome Consortium and The Cancer Genome Atlas datasets. Robust cancer biomarker signatures were extracted using a 10-fold cross-validation method of log transformation, quantile normalization, transcript ranking by area under the receiver operating characteristic curve, and stepwise logistic regression. The entire algorithm was then repeated with a new set of randomly generated training and test sets, yielding highly concordant biomarker signatures. External validation of the cancer-specific signatures yielded high sensitivity (92.0% ± 3.15%; mean ± standard deviation) and specificity (97.7% ± 2.99%) for each cancer biomarker signature. The overall performance of this RNA-Seq biomarker-generating algorithm yielded an accuracy of 90.5%. In conclusion, we demonstrate a computational model for producing highly sensitive and specific cancer biomarker signatures from RNA-Seq data, generating signatures for the top eight cancer types responsible for CUP to accurately identify tumor origin.

Multimodal treatment for multistation mediastinal lymph node adenocarcinoma: a case report

We report on a 68-year-old male with a multistation mediastinal lymph node adenocarcinoma, who had no primary lesions occurring within 48 months. After diagnosis by lymph node biopsy via right-sided thoracoscopy, the bilateral mediastinal lymphadenopathy responded to platinum-based chemotherapy. At 30 months after completion of chemotherapy, left mediastinal lymphadenopathy recurred. Left anterior mediastinal dissection via left-sided thoracoscopy was successful. After surgery, the patient did well with no primary lesions for more than a year. The etiology of mediastinal lymph node carcinoma of unknown origin is discussed.

Surgical management of unknown primary tumors metastatic to the spine

OBJECT

Patients presenting with spinal metastases from unknown primary tumors (UPTs) are rare. The authors reviewed their surgical experience to evaluate outcomes and identify predictors of survival in these patients.

METHODS

This study is a retrospective analysis of patients undergoing surgery for metastatic spine disease from UPTs between June 1993 and February 2007 at The University of Texas M. D. Anderson Cancer Center.

RESULTS

Fifty-one patients undergoing 52 surgical procedures were identified. The median age at spine surgery was 60 years. The median survival from time of diagnosis was 15.8 months (95% CI 8.1-23.6) and it was 8.1 months (95% CI 1.6-14.7) from time of spine surgery. Postoperative neurological function (Frankel score) was the same or improved in 94% of patients. At presentation, 77% had extraspinal disease, which was associated with poorer survival (6.4 vs 18.1 months; p = 0.041). Multiple sites (vs a single site) of spine disease did not impact survival (12.7 vs 8.7 months; p = 0.50). Patients with noncervical spinal disease survived longer than those with cervical disease (11.8 vs 6.4 months, respectively; p = 0.029). Complete versus incomplete resection at index surgery had no impact on survival duration (p > 0.5) or local recurrence (p = 1.0). Identification of a primary cancer was achieved in 31% of patients.

CONCLUSIONS

This is the first reported surgical series of patients with an unknown source of spinal metastases. The authors found that multiple sites of spinal disease did not influence survival; however, the presence of extraspinal disease had a negative impact. The extent of resection had no effect on survival duration or local recurrence. With an overall median survival of 8.1 months following surgery, aggressive evaluation and treatment of patients with metastatic disease of the spine from an unknown primary source is warranted.

Radiculopathy due to malignant melanoma in the sacrum with unknown primary site

Melanoma is an interesting tumor, showing the appearance of metastasis without any trace of its primary lesion. To report a very rare case of malignant melanoma in the sacrum with unknown primary origin. The authors present a case of a 52-year-old man who was admitted with increasing lower back, left buttock, and left lower extremity pain, and dysuria. Plain radiograph, computed tomography scan, and magnetic resonance imaging revealed a destructive lesion in the sacrum and left ilium, which infiltrated the spinal canal and sacroiliac joint. The tumor cells were immunoreactive for HMB-45. The pathological diagnosis was malignant melanoma. No obvious primary malignant melanoma was detected on the skin surface, on the oral or anal mucosa, or in the fundus oculi. Following radiotherapy and chemotherapy, the severe buttock pain disappeared and the patient was able to walk without impediment. However the patient died nine months after initial diagnosis. Malignant melanoma in the sacrum with an unknown primary site, showing S1 radiculopathy is reported for the first time. The melanoma could have been a metastatic tumor of the sacrum, although the primary site was not detected. The incidence of primary melanoma is increasing faster than any other cancer. Thus treatment of patients with spinal metastasis of melanoma is an important challenge for orthopedic surgeons.

Switching benchmarks in cancer of unknown primary: From autopsy to microarray

INTRODUCTION

Cancer of unknown primary (CUP) is associated with unknown biology and dismal prognosis. Information on the primary site of origin is scant and has never been analysed. We systematically reviewed all published evidence on the CUP primary site identified by two different approaches, either autopsy or microarray gene expression profiling.

METHODS

Published reports on identification of CUP primary site by autopsy or microarray-based multigene expression platforms were retrieved and analysed for year of publication, primary site, patient age, gender, histology, rate of primary identification, manifestations and metastatic deposits, microarray chip technology, training and validation sets, mathematical modelling, classification accuracy and number of classifying genes.

RESULTS

From 1944 to 2000, a total of 884 CUP patients (66% males) underwent autopsy in 12 studies after presenting with metastatic or systemic symptoms and succumbing to their disease. A primary was identified in 644 (73%) of them, mostly in the lung (27%), pancreas (24%), hepatobiliary tree (8%), kidneys (8%), bowel, genital system and stomach, as a small focus of adenocarcinoma or poorly differentiated carcinoma. An unpredictable systemic dissemination was evident with high frequency of lung (46%), nodal (35%), bone (17%), brain (16%) and uncommon (18%) deposits. Between the 1944-1980 and the 1980-2000 series, female representation increased, 'undetermined neoplasm' diagnosis became rarer, pancreatic primaries were found less often while colonic ones were identified more frequently. Four studies using microarray technology profiled more than 500 CUP cases using classifier set of genes (ranging from 10 to 495) and reported strikingly dissimilar frequencies of assigned primary sites (lung 11.5%, pancreas 12.5%, bowel 12%, breast 15%, hepatobiliary tree 8%, kidneys 6%, genital system 9%, bladder 5%) in 75-90% of the cases.

CONCLUSIONS

Evolution in medical imaging technology, diet and lifestyle habits probably account for changing epidemiology of CUP primaries in autopsies. Discrepant assignment of primary sites by microarrays may be due to the presence of 'sanctuary sites' in autopsies, molecular misclassification and the postulated presence of a pro-metastatic genetic signature. In view of the absence of patient therapeutic or prognostic benefit with primary identification, gene expression profiling should be re-orientated towards unraveling the complex pathophysiology of metastases.

Long-term survival after incomplete resection of immunohistochemically diagnosed T0N1 lung cancer: report of a case

A 63-year-old man who had undergone resection of colon cancer 15 years previously was found to have a right hilar mass on chest X-ray, and an elevated serum carcinoembryonic antigen level. The hilar lymph nodes were resected with the right upper lobe, and the initial diagnosis was colon cancer metastasis to the right hilar lymph nodes. Although the resection was incomplete, and no additional treatment was given, the patient remained free of recurrence for 10 years. This prompted us to reconsider our diagnosis using immunohistochemistry. The resected lymph nodes were found to be positive for thyroid transcription factor 1 (TTF-1) and cytokeratin 7, and negative for surfactant apoprotein (SAP), cytokeratin 20, and napsin A. The neuroendocrine markers and thyroglobulin were also negative. These findings led us to diagnose T0N1 lung cancer. There are reports of patients with clinical T0N1,2 lung cancer having exceptionally good prognoses despite noncurative treatment; however, to our knowledge, this is the first case of a patient with T0N1 lung cancer diagnosed by immunohistochemistry, with a good prognosis despite incomplete resection. In this case, TTF-1 and cytokeratin staining was particularly helpful in the differential diagnosis.

Serum tumor markers in skeletal metastasis

BACKGROUND

There have been no well-documented reports detailing the relationship between skeletal metastasis and tumor markers in a large series of patients. The purpose of our study was to assess the relationship between the clinical features of skeletal metastasis and serum tumor markers and to determine whether tumor markers are a useful modality in the differential diagnosis of skeletal metastasis.

METHODS

We retrospectively reviewed consecutive 458 patients with skeletal metastasis and divided the patients into two groups according to six clinical presenting factors. We assessed whether these groups influenced the level of the tumor markers in univariate and multivariate analysis.

RESULTS

Patients with skeletal metastasis of carcinoma had a higher level of markers CEA (P < 0.0001) and CA19-9 (P = 0.0008) than patients with primary bone tumors and hematological malignancies. Univariate analysis of clinical variables revealed that metastasis on axial skeleton, multiple skeletal metastases and visceral metastasis were associated with the serum CEA and CA19-9 levels. By multivariate analysis, metastasis on axial skeleton, multiple skeletal metastases and visceral metastasis were found to be associated with the serum CEA and CA19-9 levels. At least one of the tumor markers was elevated in 73% of all patients.

CONCLUSIONS

The higher tumor marker level (CEA, CA19-9) is predictive of metastasis on the axial skeleton, multiple skeletal metastases and visceral metastasis. Tumor markers are useful as a screening test to distinguish skeletal metastases of carcinoma from primary bone tumors or hematological malignancy from primary bone tumor and hematological malignancy.

Chemotherapy for patients with two favourable subsets of unknown primary carcinoma: active, but how effective?

Carcinoma of unknown primary (CUP) is characterized by dismal patient survival. The outcome of patients with two favourable risk CUP subsets was studied. Eighty patients diagnosed with either midline lymph node metastases (n=33) or peritoneal carcinomatosis (n=47) were analysed retrospectively. The majority had poorly differentiated adenocarcinoma or undifferentiated carcinoma, treated with platinum-taxane based chemotherapy from 1996 till 2002. Females with peritoneal carcinomatosis also underwent surgical debulking. Objective tumour regression was present in 44% of patients (nodal group 30% versus peritoneal group 53%, p=0.066). Complete responses were seen more often in peritoneal carcinomatosis patients (nodal group 9%, peritoneal group 36%, p=0.008). At a median follow up of 60 months, median progression-free and overall survival were 5 and 10 months respectively in the nodal group, 7 and 15 months in the peritoneal group. Five-year survival was 7% (nodal group 0% vs. peritoneal group 10%, p=0.05). Complete responders fared better than non-CR patients. Fewer than four metastatic sites, elevated CA 125, and normal CA 19-9 levels were favourable prognostic factors for survival. Modern combination chemotherapy has satisfactory activity, with a minority of CUP patients enjoying long-term responses. Research efforts towards complete remission consolidation and molecular profiling are imperative.

Cancer of unknown primary: changing approaches. A multidisciplinary case presentation from the Joan Karnell cancer center of pennsylvania hospital

Cancer of unknown primary is a common clinical syndrome, accounting for 2%-5% of cancer patients. A representative case is presented. This heterogenous group of disorders includes entities such as poorly differentiated carcinoma of unknown primary, adenocarcinoma of unknown primary, neuroendocrine carcinoma of unknown primary, squamous cell carcinoma of unknown primary, poorly differentiated (not otherwise specified) cancer of unknown primary, and melanoma of unknown primary. It is crucial to identify those treatment-responsive presentations of unknown primary with the greatest potential for long-term survival. This discussion emphasizes newer approaches to the diagnosis and treatment of unknown primary cancer, including advances in pathology with immunoperoxidase and molecular genetic techniques, positron emission tomography, and published chemotherapeutic trials. With the increased sophistication of pathologic and radiologic techniques, the frequency of unknown primary cancers will likely continue to decline. Further, as newer and more targeted therapies for specific types of cancer are identified, the previously held nihilism regarding the search for and identification of the primary may become less supportable.

Surgical and Ablative Treatment for Metastatic Adenocarcinoma to the Liver from Unknown Primary Tumor

Metastatic adenocarcinoma to the liver from an unknown primary tumor (UPT) carries a poor prognosis, with a median survival of 5 months. Chemotherapy has not significantly improved outcome, and effective treatment is yet to be established in these patients. We examined our experience with surgical resection and ablation of this disease to determine clinico-pathologic characteristics and treatment outcomes. We undertook a retrospective chart review of 157 patients who were treated for metastatic disease to the liver with resection or radiofrequency ablation (RFA) between 1999 and 2003. Seven patients were identified with unknown primary malignancy. Evaluation of the seven patients included complete history and physical examination, complete blood count, routine chemistries, stool Hemoccult test, chest radiograph, and computed tomography (CT) of the abdomen and pelvis. In addition, the three female patients had breast examinations and mammography. Adenocarcinoma histology was determined via CT-guided liver biopsy in all patients. Other diagnostic tests, including whole-body positron emission tomography to the measurement of various serum tumor markers, were performed in the majority of the patients. There were nine total lesions treated; six with RFA and three with hepatic resection. Median diameter of the lesions was 5.4 cm (range, 1.3–15). Two patients were treated with adjuvant and three patients with neoadjuvant and adjuvant chemotherapy. Extrahepatic sites of metastases, adrenal and skeletal, were discovered in 1 patient prior to treatment. With a median follow-up of 9 months, 1 patient is currently alive with no evidence of disease, 4 patients are alive with disease, and 2 patients died of disease. Median disease-free-interval following treatment was 6.5 months. To date, optimal treatment for metastatic adenocarcinoma to the liver UPT remains unclear. Localized treatment involving RFA or hepatic resection may be a promising addition to chemotherapy in the management of this disease.

Evaluation of the patient with carcinoma of unknown origin metastatic to bone

Metastatic carcinoma to bone of uncertain primary origin is a common clinical diagnostic scenario. I present a simple and effective staging system to identify primary malignancies. The role of clinical history, physical examination, laboratory studies, and limited radiographic studies are critical to the success of this diagnostic strategy. Needle or open biopsy frequently is needed yet usually is more effective as a confirmatory study for carcinoma or to rule out primary bone sarcomas. Patients who present with a displaced pathologic fracture require an urgent diagnostic and treatment plan that does not compromise future treatment options and provides durable skeletal reconstruction.

Diagnostic and therapeutic management of cancer of an unknown primary

Metastatic Cancer of Unknown Primary Site (CUP) accounts for approximately 3% of all malignant neoplasms and is therefore one of the 10 most frequent cancer diagnoses in man. Patients with CUP present with metastatic disease for which the site of origin cannot be identified at the time of diagnosis. It is now accepted that CUP represents a heterogeneous group of malignancies that share a unique clinical behaviour and, presumably, unique biology. The following clinicopathological entities have been recognised: (i) metastatic CUP primarily to the liver or to multiple sites, (ii) metastatic CUP to lymph nodes including the sub-sets involving primarily the mediastinal-retroperitoneal, the axillary, the cervical or the inguinal nodes, (iii) metastatic CUP of peritoneal cavity including the peritoneal papillary serous carcinomatosis in females and the peritoneal non-papillary carcinomatosis in males or females, (iv) metastatic CUP to the lungs with parenchymal metastases or isolated malignant pleural effusion, (v) metastatic CUP to the bones, (vi) metastatic CUP to the brain, (vii) metastatic neuroendocrine carcinomas and (viii) metastatic melanoma of an unknown primary. Extensive work-up with specific pathology investigations (immunohistochemistry, electron microscopy, molecular diagnosis) and modern imaging technology (computed tomography (CT), mammography, Positron Emission Tomography (PET) scan) have resulted in some improvements in diagnosis; however, the primary site remains unknown in most patients, even on autopsy. The most frequently detected primaries are carcinomas hidden in the lung or pancreas. Several favourable sub-sets of CUP have been identified, which are responsive to systemic chemotherapy and/or locoregional treatment. Identification and treatment of these patients is of paramount importance. The considered responsive sub-sets to platinum-based chemotherapy are the poorly differentiated carcinomas involving the mediastinal-retroperitoneal nodes, the peritoneal papillary serous adenocarcinomatosis in females and the poorly differentiated neuroendocrine carcinomas. Other tumours successfully managed by locoregional treatment with surgery and/or irradiation are the metastatic adenocarcinoma of isolated axillary nodes, metastatic squamous cell carcinoma of cervical nodes, or any other single metastatic site. Empirical chemotherapy benefits some of the patients who do not fit into any favourable sub-set, and should be considered in patients with a good performance status.

Cancer from an unknown primary site

Cancer from an unknown primary site (CUP) is frequently encountered in clinical practice. This review is designed to help physicians identify those patients with CUP that benefit from specific therapeutic approaches. The utility of pathologic and diagnostic tests in patients with CUP will also be discussed, as will the prognosis and appropriate treatment of these patients.

The unknown biology of the unknown primary tumour: a literature review

The unknown primary tumour (UPT) is an intriguing clinical phenomenon found in approximately 5% of all newly diagnosed patients with cancer. It is unclear whether UPT forms a distinct biological entity with specific genetic and phenotypic characteristics, or whether it is merely a clinical presentation of metastases in patients in whom the primary tumour cannot be detected and does not result in any visible clinical signs. Understanding the basic biology of UPT may shed light on this issue and, moreover, may have a direct impact on clinical care. A review of the literature revealed only a limited number of publications describing the genetic and phenotypic features of UPT, most of which focus only on the potential of these markers to predict prognosis. The question as to whether the biology of UPT is different from tumours of known primaries therefore remains unanswered. Further insight into the molecular mechanisms underlying the oncogenesis of UPT, e.g. by applying newly available DNA and gene profiling microarray techniques, will be necessary to understand its specific biology and to develop more effective treatments.

[Metastatic cáncer presentation. Validation of a diagnostic algorithm with 221 consecutive patients]

BACKGROUND

The use of a diagnostic algorithm for metastatic cancer presentation (MCP) might enhance the diagnosis of primary tumors amenable to treatment with considerable savings both in time and diagnostic examinations.

MATERIALS AND METHODS

From January 1992 to April 1997, all patients admitted with the diagnosis of MCP were prospectively studied. From each patient, a basic study consisting in a clinical interview, complete physical examination, standard blood testing with tumoral markers and chest X-ray were obtained. Patients with a negative basic study were classified as having a metastatic cancer of unknown origin (MUO); in these patients, a protocolized study (abdominal CT scan and mammography among women) were performed. Patients who after the application of the basic and protocolized studies had no primary tumor detected underwent an exhaustive investigation in order to validate the efficiency of the diagnostic algorithm.

RESULTS

Two hundred twenty-one patients were included in the study. The mean age of patients was 63 years (range: 23-82). The main symptom was of bone (30%), neurological (24%), thoracic (16%) and abdominal (16%) origin. The basic study was positive for 138 patients (62.4%), with chest X-ray and physical examination yielding the highest number of diagnoses among these patients. The histology of metastases contributed to the definite diagnosis in 31 patients. Only PSA had a high sensitivity and specificity. Eighty-three patients were classified as MUO. The protocolized study diagnosed the primary tumor in 24 patients (30%), 20 by abdominal CT scan and four by mammography; eight of these patients were deemed to be amenable to treatment. The remaining 59 patients underwent an exhaustive study, and a diagnosis was made in 13; nevertheless, none of them was considered candidate for a specific treatment. Finally, 47 patients (21%) remained undiagnosed. The predominant primary tumors included sites at the lung (42%), prostate (6%) and breast (6%). The most common metastatic locations included bone (42%), central nervous system and liver (24%), and the most common histological types were adenocarcinoma (61%) and undifferentiated carcinoma (15%).

CONCLUSIONS

Lung cancer and MUO represented 62% of MCP. The basic study oriented in two thirds of cases, and the physical examination and chest X-ray showed the highest diagnostic yield. The histology of metastases and PSA had a key, diagnostic relevance. A protocolized study based on abdominal CT scan and mammography (females) can identify the remaining treatable tumors.

A phase II study of mitomycin C, cisplatin and continuous infusion 5-fluorouracil (MCF) in the treatment of patients with carcinoma of unknown primary site

Carcinoma of unknown primary site remains a common clinical diagnosis, accounting for between 5 and 10% of all cancer patients. Numerous combination chemotherapy regimens have been used in the management of carcinoma of unknown primary site, resulting in response rates of 0-48%. We present the results of a single centre phase II study of the use of the combination of mitomycin C (7 mg m(-2) on day 1 of cycles 1, 3 and 5) cisplatin (60 mg m(-2) on day 1) and continuous infusion 5-fluorouracil (300 mg m(-2) daily), MCF, delivered as a 21-day cycle, in patients with carcinoma of unknown primary site. Thirty-one patients with a diagnosis of carcinoma of unknown primary site were treated in Aberdeen Royal Infirmary between 1997 and 2001 with MCF. In total, 136 cycles of MCF were delivered (median of 5 cycles per patient). Toxicity was acceptable, with 19% grade 3 or 4 neutropenia, 16% grade 3 or 4 thrombocytopenia and 13% grade 3 or 4 nausea and vomiting. No cases of neutropenic sepsis were seen and there were no treatment-related deaths, however, six patients developed thrombotic complications. The overall response rate was 27% (CR 3%; PR 23%). Median time to progression was 3.4 months (95% CI 1.1-5.6 months) and median overall survival was 7.7 months (95% CI 5.7-9.8 months). Survival at 1 year was 28%, and at 2 years, 10%. MCF is a tolerable regimen with comparable toxicity, response rates and survival data to most platinum-based combination chemotherapy regimens in use for this devastating disease.

Epirubicin, cisplatin, and prolonged or brief infusional 5-fluorouracil in the treatment of carcinoma of unknown primary site

The cytotoxic regimen of epirubicin, cisplatin, and continuous infusional 5-fluorouracil (ECF) has demonstrated activity in a range of malignancies, including gastroesophageal, breast, and pancreatic cancers. Prolonged infusional central venous catheter (CVC) mediated therapy is not always feasible and modifications of the 5-fluorouracil (5FU) schedule have been reported. We reviewed our experience of both the standard and a modified ECF regimen in patients diagnosed with carcinoma of unknown primary site (CUPS). A retrospective analysis of all patients diagnosed with CUPS (31 adenocarcinoma and 5 poorly differentiated carcinoma) and treated with ECF between June 1994 and June 1998 was undertaken. Thirty-six patients, median age 56 (range: 24-74), were treated thrice-weekly with 50 mg/m2 epirubicin, 60 mg/m2 cisplatin, and 5-FU administered either by continuous infusion 200 mg/m2/d via a CVC (standard ECF) or as a 6-h infusion 600 mg/m2 through a peripheral venous catheter (modified ECF). Thirteen patients were treated with standard ECF and 23 received modified ECF. The median number of cycles administered was 4 (range: 1-10). Thirty-two patients had evaluable disease, seven (22%; 95% confidence interval: 8-36%) demonstrated a partial response, including three patients that received standard ECF and four treated with modified ECF. There were no complete responses. The median survival for all 36 patients was 9.0 mo. Median survival for patients treated with standard ECF was 11.7 mo as compared to 5.1 mo for the modified ECF schedule (p = 0.052). Liver involvement and elevation of serum CA19.9 were identified as possible adverse prognostic factors. Both regimens were well tolerated, with the only grade 3/4 toxicity recorded being leukopenia (four patients), nausea/vomiting (seven patients), and diarrhea (one patient). CVC complications in the standard ECF group were thrombosis (one patient) and infection (three patients). There were no treatment-related deaths. We conclude that ECF, whether modified or standard, has modest activity in the setting of CUPS. Patient survival is comparable to survival documented in previous reports of CUPS treatment. The apparent survival difference between the two ECF schedules may be the result of patient selection factors. The optimal treatment of CUPS remains unknown and can only be determined through randomized controlled trials.

Unknown primary tumours

Unknown primary tumours (UPTs) are defined by the absence of a primary tumour in biopsy proved metastatic cancer. These tumours have a specific biology with clinical characteristics of rapid progression and random atypical metastases. Cytogenetic abnormalities have been demonstrated, particularly deletion of chromosome 1p. Diagnostic evaluation that includes pathology review, physical examination, chest radiography, computed tomography of the abdomen, and mammography is directed at the identification of treatable subsets. Based on clinicopathological criteria, therapy responsive subsets of patients with UPTs can be defined. These subsets have a better prognosis than the average median survival time of four months in patients with UPTs.

Management of adenocarcinoma of unknown primary with a 5-fluorouracil-cisplatin chemotherapy regimen (CFTam)

BACKGROUND

Adenocarcinoma of unknown primary comprises up to 10% of metastatic malignant disease. With few exceptions this diagnosis carries a very poor prognosis of a few months with minimal survival advantage to chemotherapy. However there is the possibility that chemotherapy can improve symptom control and quality of life.

PATIENTS AND METHODS

Forty-four patients with adenocarcinoma of unknown primary received CFTam chemotherapy regimen (5-FU 750 mg/m2/day by protracted infusion for five days, cisplatin 60 mg/m2 once and tamoxifen 20 mg daily on a 21-day cycle). Disease response and toxicity were collected and survival compared to patients who were not treated or who received different chemotherapy regimens.

RESULTS

Overall response to CFTam was 27% with a median duration of 10 months (range 4-26 months). The chemotherapy was well tolerated with no grade 4 non-haematological toxicity and only three patients (7%) grade 4 neutropaenia with only two (5%) patients developing sepsis. There were no toxic deaths. Performance status was maintained or improved in responders.

CONCLUSIONS

CFTam is a well tolerated chemotherapy regimen with similar efficacy to other regimens described in the treatment of adenocarcinoma of unknown primary. In the absence of a significant survival advantage there is a need to conduct randomised trials of chemotherapy versus best supportive care to quantify any improvement in quality of life or symptom control.

Determining the site of the primary cancer in patients with skeletal metastasis of unknown origin: a retrospective study

BACKGROUND

When skeletal metastasis is the presenting problem and the primary site is occult, there is a need to identify the primary site as soon as possible. However, the search for the primary tumor is often time-consuming and difficult. The purpose of this study was to analyze the efficacy of particular diagnostic approaches and to devise an efficient and optimal diagnostic strategy.

METHODS

Among 213 patients with skeletal metastasis treated between 1990 and 1996 were 64 in whom skeletal lesions were the first manifestation of malignancy. The authors retrospectively analyzed both the final diagnosis and the process by which it was made in these 64 cases.

RESULTS

The primary cancer was identified antemortem in 56 (88%) of the 64 patients by examination and in 3 patients at autopsy. Lung carcinoma, the most frequently observed primary lesion, was identified in 23 patients. Other primary lesions were prostate carcinoma in 11 patients, breast carcinoma in 5, and hepatocellular carcinoma in 5. The primary malignancy was not determined in 5 patients. Thoracic and abdominal computed tomography (CT) scans were useful, especially in the diagnosis of patients with lung, hepatocellular, renal cell, and pancreatic carcinomas. Tumor markers were abnormally elevated in 73% of patients with carcinomas.

CONCLUSIONS

Although thoracic and abdominal CT scans were useful, examination of the gastrointestinal tract and pelvic CT scan seldom revealed the primary lesion and therefore should not be performed as an initial routine study in the absence of abdominal symptoms. Tumor markers are useful in differentiating carcinoma from hematologic malignancy and primary bone tumor.

Metastatic adenocarcinoma of unknown primary origin

Adenocarcinomas account for up to 60% of all metastatic neoplasms of unknown primary origin. In general, adenocarcinomas are the most difficult metastatic tumor to accurately identify the primary site. Some metastatic adenocarcinomas have distinctive histological features that allow for their site determination (eg, colonic adenocarcinoma, bronchioloalveolar cell carcinoma), although the majority of metastatic adenocarcinomas have histological features that are not distinctive enough to allow for a specific diagnosis of their origin. For this reason, electron microscopy and immunohistochemistry have been used to help identify the exact type (origin) of metastatic adenocarcinomas. Relatively specific ultrastructural features used to diagnose metastatic adenocarcinomas of unknown primary origin include tubular myelin, intranuclear surfactant apoprotein tubular inclusions, Clara cell granules, uniform short microvilli with filamentous cores and core rootlets, Langerhans cells associated with neoplastic cells, cytoplasmic hyaline globules, lipid droplets, glycogen, and cytoplasmic crystals. Only a few of these ultrastructural features are absolutely specific. Relatively specific immunohistochemical tests used to diagnose metastatic adenocarcinomas of unknown primary origin include prostate-specific antigen, thyroglobulin, estrogen and progesterone receptor proteins, thyroid transcription factor-I, and surfactant apoproteins. Of these, prostate-specific antigen and thyroglobulin are the most specific. The purpose of this article is to discuss the use of electron microscopy and immunohistochemistry in the site-specific diagnosis of metastatic adenocarcinomas of unknown primary origin.

[Carcinoma of unknown primary site. Apropos of 100 patients treated at the Montpellier regional center of cancer prevention]

PURPOSE

Carcinomas of unknown primary site are frequent neoplasms which raise diagnostic and therapeutic problems in clinical practice.

METHODS

Clinical records of 100 patients with carcinoma of unknown primary site whose clinical management took place at the Centre Regional de Lutte Contre le Cancer de Montpellier were retrospectively reviewed. Initial clinical and biological characteristics, pre-treatment evaluation, therapies and outcome were recorded.

RESULTS

Three main histological types were observed: adenocarcinoma (66 patients), poorly differentiated carcinoma (19 patients), epidermoid carcinoma (11 patients). Bone, lung, lymph nodes and liver were the most frequently involved metastatic sites. Analysis of the investigations aimed at identifying the primary site (none of which being positive) showed 68 different combinations in 100 patients. Anemia (< 100 g/L) was observed in 10 patients, while serum alkaline phosphatase was increased in 42 patients. Seven patients died before any therapy. Chemotherapy or radiotherapy was advocated in 70 and 59 patients, respectively. Thirty-six patients had concomitant chemoradiotherapy. Chemotherapy included a platinum derivative in 53 patients. The median number of cycles was four. Nine objective responses were observed, six of which occurred in patients who were receiving platinum-based chemotherapy. Ninety-six deaths were encountered, 95 due to the disease progress and one due to an intercurrent cause. The median survival was 9 months. Univariate analysis identified two prognostic factors: the number of metastatic sites and the serum alkaline phosphatase.

CONCLUSIONS

This retrospective study confirms the difficulties in the management of patients with carcinomas of unknown primary site. A literature review suggests limited diagnostic investigations in clinical practice with the aim of identifying tumors of potential prognostic (breast and ovary) or therapeutic (prostate) value. Apart from specific subgroups of patients for whom specific therapy is recommended, there is no current standard chemotherapy.

Skeletal metastasis as the initial clinical manifestation of metastatic carcinoma in 19 dogs

Although the skeleton represents a potentially important target for the metastatic spread of carcinoma, the clinicopathologic features of skeletal metastases in dogs have not been documented extensively. In particular, no reports have focused on dogs in which skeletal metastasis was the initial clinical manifestation of their malignancy. Medical records were reviewed for dogs with skeletal carcinoma and cases were subdivided into 2 groups based upon the temporal relationship between the diagnosis of carcinoma and recognition of skeletal metastases. In 19 of 24 (79%) dogs, skeletal metastasis was the initial clinical manifestation of malignancy, and these dogs were studied in detail. Most affected dogs were elderly and weighted less than 25 kg. Thirty-six skeletal lesions were identified in 19 dogs. Skeletal metastases occurred most frequently in the axial skeleton and proximal long bones. Only 4 of 36 (11%) skeletal carcinomas occurred distal to the elbow or stifle. Mammary gland, prostate, and urinary bladder were the most common primary sites. In 11 of 19 (58%), dogs, the primary tumor could not be determined, and in 6 of these dogs, the primary tumor could not be identified despite complete postmortem evaluation. Physical examination and abdominal ultrasonography were most valuable in detecting the primary tumor. Although biopsy or fine-needle aspirate of skeletal lesions was essential in the diagnosis of skeletal carcinoma, these procedures did not yield definitive information on the primary tumor site. This report documents that the majority of skeletal metastases are diagnosed in dogs without a previous diagnosis of carcinoma. Detection of the primary tumor in these cases may be challenging, and skeletal metastases are frequently attributable to carcinoma of unknown origin.

Continuous infusion cisplatin and etoposide chemotherapy for cancer of unknown primary site (CUPS) in Taiwan, a region with a high prevalence of endemic viral infections

BACKGROUND

To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections.

METHOD

Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating.

RESULTS

The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population.

CONCLUSION

Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.

Detection of unknown occult primary tumors using positron emission tomography

BACKGROUND

The potential of positron emission tomography (PET) with 18F-fluoro-2-deoxy-D-glucose (FDG) to detect primary tumors after unsuccessful conventional diagnostic workup was assessed in patients with metastatic disease from an unknown primary tumor.

METHODS

Twenty-nine patients with various histologic types of metastases from an unknown primary site were studied after unsuccessful conventional diagnostic workup. The patients received 370 megabecquerels (MBq) (10 millicuries) FDG intravenously and whole body scans were made after 30 minutes after injection onward.

RESULTS

All but one known metastatic tumor sites were visualized. Additional metastases were discovered in five patients. With FDG-PET the primary tumor was identified in 7 patients (24%): in 2 patients with carcinoma of the nasopharynx, in 1 patient with plasmacytoma of the base of the tongue, in 1 patient with carcinoma of the lung, in 1 patient with carcinoma of the colon, and in 2 patients with breast carcinoma. FDG-PET did not identify a primary tumor in the remaining 22 patients (76%). Despite a negative PET study, the primary lesion was identified in a later phase in 3 of these patients (14%). Survival was not altered by discovery of the primary tumor.

CONCLUSIONS

A previously unknown primary tumor was able to be identified with FDG-PET in 7 of 29 patients after an unsuccessful conventional diagnostic workup. However, the clinical relevance of PET information in this setting is limited.

A phase I/II study of leucovorin, carboplatin and 5-fluorouracil (LCF) in patients with carcinoma of unknown primary site or advanced oesophagogastric/pancreatic adenocarcinomas

Carcinoma of unknown primary site (CUPS) accounts for 5-10% of all malignancies. Forty patients with metastatic CUPS or advanced oesophagogastric/pancreatic adenocarcinomas were recruited. Eligibility included ECOG performance status 0-2, minimum life expectancy of 3 months and measurable disease. The regimen consisted of bolus intravenous 5 fluorouracil (5-FU) and leucovorin (20 mg m-2) days 1-5 and carboplatin (AUC5) on day 3. The leucovorin/carboplatin/5-FU (LCF) was repeated every 4 weeks. The starting dose of 5-FU was 350 mg m-2 day-1 with escalation to 370 and then 400 mg m-2 day -1 after the toxicity at the previous level had been assessed. The maximum tolerated dose (MTD) was defined as the dosage of 5-FU that achieved 60% grade 3/4 toxicity. In addition, objective and symptomatic responses, quality of life and survival were assessed. The MTD of 5-FU in the LCF regimen was 370 mg m-2. The predominant toxicity was asymptomatic marrow toxicity. The 350 mg m-2 level was then expanded. There were two toxic deaths due to neutropenic sepsis, one at 370 mg m-2 after one course and one at 350 mg m-2 after four courses. The objective response rate was 25% with one complete response (CR) and nine partial responses (PRs). The median duration of response was 3.4 months (range 1-10). The CR and eight of the nine PRs were in CUPS patients. Twelve patients developed progressive disease on LCF. Median survival for all 40 patients was 7.8 months (10 months median survival for those treated at 350 mg m-2). The majority of patients described a symptomatic improvement with LCF chemotherapy. The recommended dose of 5-FU for future studies is 350 mg m-2 combined with leucovorin 20 mg m-2 and carboplatin (AUC5).

Unknown primary carcinoma: randomised studies are needed to identify optimal treatments and their benefits

This is a retrospective review of 101 patients with unknown primary carcinoma (UPC) treated between 1989 and 1994, on whom data were collected prospectively. 92 patients received platinum-based chemotherapy and 9 had single agent 5-fluorouracil (5-FU). In the platinum group, an objective response rate of 37.2% was seen, with a median duration of 4.5 months (range 1.9-17.5). There were no responses with 5-FU alone, while median survival was 6.4 months and was not different from the platinum group (P = 0.09). Considerable symptomatic resolution was noted, although the contribution of chemotherapy alone to this is difficult to define. The impact of tumour response on quality of life and survival in UPC requires further elucidation in prospective studies with a "best supportive care' arm. The superiority of platinum-based treatments reported in selected subgroups cannot be applied to the whole spectrum of UPC.

Survival rates of patients with metastatic spinal cancer after scintigraphic detection of abnormal radioactive accumulation

STUDY DESIGN

This retrospective study analyzes the timing of spinal metastases and the survivability of patients with cancer after the detection of spinal metastases.

OBJECTIVE

To evaluate the timing of spinal metastases in primary lesions and the survivability of patients with metastatic spinal tumors.

SUMMARY OF BACKGROUND DATA

Few studies have analyzed the influence of primary lesions on survival rates of patients with metastatic spinal tumors.

METHODS

This is a review of bone scintigraphy that was performed serially in patients with pulmonary cancer, breast cancer, prostatic cancer, cervical cancer, renal cancer, and gastric cancer from 1980 to 1991. To exclude false positive cases, the spinal areas showing abnormal accumulation on bone scintigrams were further examined by other methods of diagnostic imaging. The timing of scintigraphic detection of spinal metastases and the survivability were studied in 425 patients with spinal metastases. The survivability after spinal accumulation was determined by the Kaplan-Meier survival curve.

RESULTS

The mean period, from the diagnosis of the primary lesion to the detection of abnormal accumulation in the spine, was shortest in pulmonary cancer (3.6 +/- 6.1 months), and it was longest in breast cancer (29.4 +/- 33.5 months). The 1-year survival rate was high in breast cancer (78%) and prostatic cancer (83%), and it was low in pulmonary cancer (22%) and gastric cancer (0%), respectively. The 6-month survival rate of gastric cancer was 15%.

CONCLUSIONS

When managing metastatic spinal tumors, it is essential to select therapeutic methods based on adequate consideration of the features of primary lesions and the expected prognosis.

How should cancer presenting as a malignant pleural effusion be managed?

The objective of the study was to review the natural history of patients with a malignant pleural effusion but without obvious evidence of a primary, to assess the value of investigations used to look for a primary and to assess the response to palliative chemotherapy. This was done by a retrospective study of patients' notes at the Lung Unit, Royal Marsden Hospital, Sutton, Surrey. Improvement in tumour-related symptoms (and duration) on chemotherapy was assessed by the patient before the first course of chemotherapy and following each course using simple descriptive criteria as follows: (1) complete disappearance of symptoms (CR); (2) good improvement in symptoms (PR); (3) minor or no change in symptoms (NC); (4) worse symptoms (PD). Pleural effusion objective response (and duration) according to Hamed definition: success defined as a continued absence of reaccumulation of pleural fluid on all follow-up radiographs; any reaccumulation was regarded as a treatment failure. Overall survival was measured from the date of histological/cytological diagnosis to death. The study included 42 patients, 27 males and 15 females with a median age of 55 years. A primary was found in 15 patients (36%), and considered to be lung cancer. A total of 11/32 (34%) had a thoracic computed tomography (CT) scan with abnormalities compatible with a diagnosis of lung primary. When thoracic CT scan was negative, fibre optic bronchoscopy was always negative (0/13). Abdominal and pelvic CT scan, abdominal ultrasound, pelvic ultrasound and mammograms failed to reveal the primary. Twenty-three patients underwent local treatment and 37 received systemic chemotherapy. A total of 29/37 (78%) patients achieved symptomatic improvement (median duration, 6 months) and 32/37 (86%) an objective response of their pleural effusion on chemotherapy (median duration, 6 months). The median survival of the whole group was 12 months (3-60+ months). In this series the thoracic CT led to a diagnosis of lung primary in 34% of the cases. Other radiological examinations and bronchoscopy were unhelpful. Chemotherapy achieved symptom relief in 78% of patients.

Primary peritoneal carcinoma: a treatable subset of patients with adenocarcinoma of unknown primary

The syndrome of adenocarcinoma of unknown primary (ACUP) is a frequent problem in both medical and surgical practice. The prognosis is poor, the median lifespan being 4 months. In general, multiple invasive procedures aimed at determining the primary tumour are not warranted due to the low frequency of detecting a tumour for which adequate treatment exists. In this paper we wish to highlight a subset of female patients presenting with malignant ascites and no evidence of a pelvic mass, who on laparotomy were found to have primary peritoneal papillary serous adenocarcinoma. These tumours must be regarded as a potentially treatable subset of patients with ACUP in view of their frequent response to chemotherapy and relatively good prognosis.