Lung cancer patient

The following two distinctly different issues should be taken into account when planning patient care following curative-intent therapy for lung cancer: adequate follow-up to manage complications related to the curative-intent therapy; and surveillance to detect recurrences of the primary lung cancer and/or development of a new primary lung cancer early enough to allow potentially curative retreatment. Follow-up for complications should be performed by the specialist responsible for the curative-intent therapy and should last 3 to 6 months. Recurrences of the original lung cancer will be more likely during the first 2 years after curative-intent therapy, but there will be an increased lifelong risk of approximately 1 to 2% per year of developing a metachronous, or new primary, lung cancer. A standard surveillance program for these patients is recommended based on periodic visits, with chest-imaging studies and counseling patients on symptom recognition. Whether subgroups of patients with a higher risk of developing a metachronous lung cancer (eg, those patients whose primary lung cancer was radiographically occult or central and those patients surviving for > 2 years after treatment for small cell lung cancer) should have a more intensive surveillance program is presently unclear. The surveillance program should be coordinated by a multidisciplinary tumor board and overseen by the physician who diagnosed and initiated therapy for the original lung cancer. Smoking cessation is recommended for all patients following curative-intent therapy for lung cancer.

Key words: lung cancer; metachronous tumors; recurrence; surveillance

Abbreviations: NSCLC = non-small cell lung cancer; PET = positron emission tomography

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Approximately 170,000 new cases of lung cancer are diagnosed annually in the United States. (1) Unfortunately, only about 50 to 55% of patients with newly diagnosed lung cancer will have localized disease and will be candidates for potentially curative treatment. (2) Furthermore, some patients with localized non-small cell lung cancer (NSCLC) either may refuse potentially curative surgical therapy or may be unable to tolerate surgery because of limiting comorbid cardiopulmonary disease or other diseases. Consequently, it has been estimated that only 35,000 patients underwent curative-intent surgical resection for NSCLC in 1998. (3) Smaller numbers of patients will receive curative-intent radiation therapy for localized NSCLC and some combination of curative-intent chemotherapy and radiation therapy for the treatment of localized small cell carcinoma.

Two distinctly different issues should be taken into account when planning patient care following curative-intent therapy for lung cancer. First, adequate follow-up should be ensured to manage complications related to the curative-intent therapy itself. This should be a specialist-directed process. The thoracic surgeon should be responsible for managing complications related to any surgical procedures that have been performed, as should the radiation oncologist and the oncologist be responsible for managing complications related to radiation therapy and chemotherapy, respectively. In most cases, this specialist-directed follow-up should be transient.

Second, a surveillance program should be considered to detect recurrences of the primary lung cancer and/or the development of a new primary lung cancer early enough to allow potentially curative retreatment. Numerous guidelines have been published regarding the management of lung cancer. Several of these guidelines include recommendations for a posttreatment surveillance program. These recommendations will be summarized and compared. Available data on rates, patterns, and diagnostic tools for identifying a recurrence of the primary lung cancer and/or the development of a second primary lung cancer will be reviewed as the basis for recommendations on an ongoing surveillance program following curative-intent therapy for lung cancer. Issues related to follow-up for palliative therapy of lung cancer will not be discussed (see article on palliative treatment in this supplement).

METHODS AND DEFINITIONS

Methods

Published guidelines on lung cancer diagnosis and management were identified by a systematic review of the literature and were evaluated (see article on methods and grading in this supplement). Those guidelines, including recommendations that are specific to the follow-up and surveillance of patients with lung cancer after receiving curative-intent therapy, were identified for inclusion in this section. Supplemental material appropriate to this topic was obtained by a literature search of a computerized database (MEDLINE) and a review of the reference lists of relevant articles. Recommendations were developed by the section editor and writing committee, were graded by a standardized method (see article on methods and grading in this supplement) and then reviewed by all section editors, the Chair of the lung cancer panel, and the Co-Chair of the lung cancer panel.

Definitions

A difficult issue in the surveillance of the lung cancer patient following curative-intent therapy is distinguishing between a recurrence of the original lung cancer and the identification of a new primary, or metachronous, lung cancer. Martini and Melamed (4) proposed criteria for making this distinction in 1975. One confusing aspect of these criteria was the inclusion of synchronous lung cancers, which were described as physically distinct and separate from the primary tumor. In the original series by Martini and Melamed, (4) 15 of the 18 patients with synchronous lung cancers were identified at the time of the initial treatment. In current lung cancer staging terminology, these cancers would have been described either as satellite tumor nodules, if they were within the same lobe as the primary tumor, or as intrapulmonary metastases, if they were not within the same lobe. (2) With current imaging capability, synchronous lung cancer usually would be discovered prior to the performance of curative-intent surgical resection of the primary lung cancer. Hence, synchronous lung cancers should not be considered an issue in the surveillance of the lung cancer patient following curative-intent therapy.

There are also difficulties with the criteria that Martini and Melamed (4) used for diagnosing metachronous tumors (Table 1). If the primary lung cancer had a mixed histology, the histologic pattern of a second cancer might not adequately distinguish a recurrence from a metachronous tumor. After curative-intent surgical resection, it would not be possible for a newly recognized cancer to have intrapulmonary lymphatics in common with the original lung cancer. Because systematic mediastinal lymph node sampling is included in the procedure for curative-intent lung cancer surgery, identifying mediastinal nodes in common between the new and old lung cancer also would be problematic. The choice of a tumor-free interval of 2 years for distinguishing a metachronous lung cancer from a recurrence of lung cancer with similar histology was arbitrary. Although the most appropriate tumor-free interval for making this distinction has not been defined (nor has it even been determined whether such an interval is possible to define), Detterbeck and colleagues have suggested (see article on special treatment issues in this supplement) that a 4-year interval might be more appropriate. Based on these considerations, it might be appropriate to revise the criteria of Martini and Melamed (4) for identifying metachronous tumors (Table 1). Whichever criteria are used, Martini and Melamed remind us that the distinction between a new primary lung cancer and a recurrence of the original lung cancer is not as important as determining whether the tumor can be treated with curative intent. (4)

CURRENT GUIDELINES

Four guidelines (5-8) were identified that included specific recommendations for surveillance methods in patients with NSCLC following curative-intent therapy. Two guidelines (8,9) provided specific recommendations for patients with small cell lung cancer. These guidelines were developed by a consensus of expert panels. In addition, published information is available on surveillance methods for patients following curative-intent therapy for NSCLC that have been used by two leading cancer institutes in the United States and one in Japan. (10-12) The specific recommendations from the guidelines and institutional practices are summarized in Tables 2 and 3. One other guideline (13) provided only the general recommendation that respiratory physicians should develop with their colleagues an explicit follow-up policy that would be appropriate to the needs and resources of the patient and health-care providers.