When BAC recurs after surgery, the recurrences are local in about three-quarters of cases, a rate higher than other forms of NSCLC, which tends to recur distantly.

The treatment of choice in any patient with BAC is complete surgical resection, typically via lobectomy or pneumonectomy, with concurrent ipsilateral lymphadenectomy.

Non-mucinous BACs are highly associated with classical EGFR mutations, and thus are often responsive to targeted chemotherapy with erlotinib and gefitinib. K-ras mutations are rare in nm-BAC.

Mucinous BAC, in contrast, is much more highly associated with K-ras mutations and wild-type EGFR, and are thus usually insensitive to the EGFR tyrosine kinase inhibitors. In fact, there is some evidence that suggests that the administration of EGFR-pathway inhibitors to patients with K-ras mutated BACs may even be harmful.

Complete radical surgical resection is the treatment of choice for EMECL, and in most cases, results in long-term survival or cure.

MCACL has a much more favorable prognosis than most other forms of adenocarcinoma and most other NSCLC's. Cases have been documented of continued growth of these lesions over a period of 10 years without symptoms or metastasis. The overall mortality rate appears to be somewhere in the vicinity of 18% to 27%, depending on the criteria that are used to define this entity.

For treatment purposes, MCACL has been traditionally considered a non-small cell lung carcinoma (NSCLC). Complete radical surgical resection is the treatment of choice.

There is virtually no data regarding new molecular targets or targeted therapy in the literature to date. Iwasaki and co-workers failed to find mutations of the epidermal growth factor receptor (EGFR) or the cellular Kirsten rat sarcoma virus oncogene "K-ras" in one reported case.

Because of its rarity, there have been no randomized clinical trials of treatment of GCCL, and all information available derives from small retrospective institutional series or multicenter metadata.

Because LCLC-RP is so rare, no clinical trials have ever been conducted that specifically address treatment of this lung cancer variant. Because LCLC-RP is considered a form of non-small cell lung carcinoma (NSCLC), most physicians adhere to published NSCLC treatment guidelines in rhabdoid carcinoma cases. When possible, radical surgical resection with curative intent is the primary treatment of choice in early stage NSCLC's, and can be administered with or without adjuvant, neoadjuvant, or palliative chemotherapy and/or radiotherapy, depending on the disease stage and performance status of the individual patient.

In numerous clinical trials conducted in NSCLC, several different platinum-based chemotherapy regimens have been shown to be more-or-less equally effective. LCLC's, as a subtype of NSCLC, have traditionally been included in many of these clinical trials, and have been treated like other NSCLC's. More recent trials, however, have shown that some newer agents may have particular effectiveness in prolonging survival of LCLC patients. Pemetrexed, in particular, has shown significant reduction in the hazard ratio for death when used in patients with LCLC. Taxane-based (paclitaxel, docetaxel) chemotherapy was shown to induce a complete and sustained response in a liver metastasis in a case of LCC-RP. A later-appearing metastasis within mediastinal lymph nodes in the same case also showed a durable response to a taxane alone.

There have also been reports of rhabdoid carcinomas expressing vascular endothelial growth factor (VEGF), suggesting that targeted molecular therapy with VEGF blocking monoclonal antibodies such as bevacizumab may be active in these variants. However, evidence suggests that caution must be used when treating a cavitated rhabdoid tumor, one that contains significant components of squamous cell differentiation, or large tumors with containing major blood vessels, due to the potential high risk of life-threatening pulmonary hemorrhage.

A recent study reported a case wherein 2 courses of adjuvant therapy with cisplatin and paclitaxel, followed by oral gefitinib, were used after complete resection. The patient had had no recurrence 34 months later.

As large-volume LCLC-RP may show significant central necrosis and cavitation, prudence dictates that oncologists use extreme caution if contemplating the therapeutic use of bevacizumab, other anti-VEGF compounds, or anti-angiogenesis agents in general, which have been associated with a greatly increased risk of severe hemorrhage and hemoptysis that may be quickly fatal in cavatated pulmonary squamous cell carcinomas. Similar elevated risks have also been noted in tumors located near, or containing, large blood vessels.,

The prognosis of EMECL is relatively good, and considerably better than most other forms of NSCLC. The skull and dura are possible sites for metastasis from pulmonary EMC. The MIB-1 index is a predictive marker of malignant potential.

The true incidence, prevalence, and mortality of GCCL is generally unknown due to a lack of accurate cancer data on a national level. It is known to be a very rare tumor variant in all populations examined, however. In an American study of a database of over 60,000 lung cancers, GCCL comprised between 0.3% and 0.4% of primary pulmonary malignancies, with an age-adjusted incidence rate of about 3 new cases per million persons per year. With approximately 220,000 total lung cancers diagnosed in the US each year, the proportion suggests that approximately 660 and 880 new cases are diagnosed in Americans annually.

However, in a more recent series of 4,212 consecutive lung cancer cases, only one (0.024%) lesion was determined to be a "pure" giant-cell carcinoma after complete sectioning of all available tumor tissue. While some evidence suggests GCCL may have been considerably more common several decades ago, with one series identifying 3.4% of all lung carcinomas as giant-cell malignancies, it is possible that this number reflect

Most published case series and reports on giant cell-containing lung cancers show that they are diagnosed much more frequently in men than they are in women, with some studies showing extremely high male-to-female ratios (12:1 or more). In a study of over 150,000 lung cancer victims in the US, however, the gender ratio was just over 2:1, with women actually having a higher relative proportion of giant-cell cancers (0.4%) than men (0.3%).

Giant-cell carcinomas have been reported to be diagnosed in a significantly younger population than all non-small-cell carcinomas considered as a group. Like nearly all lung carcinomas, however, GCCs are exceedingly rare in very young people: in the US SEER program, only 2 cases were recorded to occur in persons younger than 30 years of age between 1983 and 1987. The average age at diagnosis of these tumors has been estimated at 60 years.

The vast majority of individuals with GCCL are heavy smokers.

Although the definitions of "central" and "peripheral" can vary between studies, GCCL are consistently diagnosed much more frequently in the lung periphery. In a review of literature compiled by Kallenburg and co-workers, less than 30% of GCCLs arose in the hilum or other parts of the "central" pulmonary tree.

A significant predilection for genesis of GCCL in the upper lobes of victims has also been postulated.

In ES-SCLC, combination chemotherapy is the standard of care, with radiotherapy added only to palliate symptoms such as dyspnea, pain from liver or bone metastases, or for treatment of brain metastases, which, in small-cell lung carcinoma, typically have a rapid, if temporary, response to whole brain radiotherapy.

Combination chemotherapy consists of a wide variety of agents, including cisplatin, cyclophosphamide, vincristine and carboplatin. Response rates are high even in extensive disease, with between 15% and 30% of subjects having a complete response to combination chemotherapy, and the vast majority having at least some objective response. Responses in ES-SCLC are often of short duration, however.

If complete response to chemotherapy occurs in a subject with SCLC, then prophylactic cranial irradiation (PCI) is often used in an attempt to prevent the emergence of brain metastases. Although this treatment is often effective, it can cause hair loss and fatigue. Prospective randomized trials with almost two years follow-up have not shown neurocognitive ill-effects. Meta-analyses of randomized trials confirm that PCI provides significant survival benefits.

A very large number of clinical trials have been conducted in "pure" SCLC over the past several decades. As a result, evidence-based sets of guidelines for treating monophasic SCLC are available. While the current set of SCLC treatment guidelines recommend that c-SCLC be treated in the same manner as "pure" SCLC, they also note that the evidence supporting their recommendation is quite weak. It is likely, then, that the optimum treatment for patients with c-SCLC remains unknown.

The current generally accepted standard of care for all forms of SCLC is concurrent chemotherapy (CT) and thoracic radiation therapy (TRT) in LD, and CT only in ED. For complete responders (patients in whom all evidence of disease disappears), prophylactic cranial irradiation (PCI) is also given. TRT serves to increase the probability of total eradication of residual locoregional disease, while PCI aims to eliminate any micrometastases to the brain.

Surgery is not often considered as a treatment option in SCLC (including c-SCLC) due to the high probability of distant metastases at the time of diagnosis. This paradigm was driven by early studies showing that the administration of systemic therapies resulted in improved survival as compared to patients undergoing surgical resection. Recent studies, however, have suggested that surgery for highly selected, very early-stage c-SCLC patients may indeed improve outcomes. Other experts recommend resection for residual masses of NSCLC components after complete local tumor response to chemotherapy and/or radiotherapy in c-SCLC.

Although other combinations of drugs have occasionally been shown to be noninferior at various endpoints and in some subgroups of patients, the combination of cisplatin or carboplatin plus etoposide or irinotecan are considered comparable first-line regimens for SCLC. For patients who do not respond to first line therapy, or who relapse after complete remission, topotecan is the only agent which has been definitively shown to offer increased survival over best supportive care (BSC), although in Japan amirubicin is considered effective as salvage therapy.

Importantly, c-SCLC is usually much more resistant to CT and RT than "pure" SCLC. While the mechanisms for this increased resistance of c-SCLC to conventional cytotoxic treatments highly active in "pure" SCLC remain mostly unknown, recent studies suggest that the earlier in its biological history that a c-SCLC is treated, the more likely it is to resemble "pure" SCLC in its response to CT and RT.

All in all, small-cell carcinoma is very responsive to chemotherapy and radiotherapy, and in particular, regimens based on platinum-containing agents. However, most people with the disease relapse, and median survival remains low.

In "limited-stage" disease, median survival with treatment is 14–20 months, and about 20% of patients with limited-stage small-cell lung carcinoma live 5 years or longer. Because of its predisposition for early metastasis, the prognosis of SCLC is poor, with only 10% to 15% of patients surviving 3 years.

The prognosis is far more grim in "extensive-stage" small-cell lung carcinoma; with treatment, median survival is 8–13 months; only 1–5% of patients with extensive-stage small-cell lung carcinoma treated with chemotherapy live 5 years or longer.

Genetic changes are very high in SCLC and LCNEC, but usually low for TC, intermediate for AC.

In most series, LCLC's comprise between 5% and 10% of all lung cancers.

According to the Nurses' Health Study, the risk of large cell lung carcinoma increases with a previous history of tobacco smoking, with a previous smoking duration of 30 to 40 years giving a relative risk of approximately 2.3 compared to never-smokers, and a duration of more than 40 years giving a relative risk of approximately 3.6.

Another study concluded that cigarette smoking is the predominant cause of large cell lung cancer. It estimated that the odds ratio associated with smoking two or more packs/day for current smokers is 37.0 in men and 72.9 in women.

Although reliable and comprehensive incidence statistics are nonexistent, LCLC-RP is a rare tumor, with only a few hundred cases described in the scientific literature to date. LCLC's made up about 10% of lung cancers in most historical series, equating to approximately 22,000 cases per year in the U.S. Of these LCLC cases, it is estimated that about 1% will eventually develop the rhabdoid phenotype during tumor evolution and progression. In one large series of 902 surgically resected lung cancers, only 3 cases (0.3%) were diagnosed as LCLC-RP. In another highly selected series of large-cell lung carcinoma cases, only 4 of 45 tumors (9%) were diagnosed as the rhabdoid phenotype using the 10% criterion, but another 10 (22%) had at least some rhabdoid cell formation. It appears likely, therefore, that LCLC-RP probably comprises between 0.1% and 1.0% of all lung malignancies.

Similar to nearly all variants of lung carcinoma, large cell lung carcinoma with rhabdoid phenotype appears to be highly related to tobacco smoking. It also appears to be significantly more common in males than in females.

Large-cell carcinoma (LCC) is a heterogeneous group of undifferentiated malignant neoplasms that lack the cytologic and architectural features of small cell carcinoma and glandular or squamous differentiation. LCC is categorized as a type of NSCLC (Non-Small Cell Carcinoma) which originates from epithelial cells of the lung.

Adenosquamous lung carcinoma (AdSqLC) is a biphasic malignant tumor arising from lung tissue that is composed of at least 10% by volume each of squamous cell carcinoma (SqCC) and adenocarcinoma (AdC) cells.

Current consensus is that the long-term prognosis of c-SCLC patients is determined by the SCLC component of their tumor, given that "pure" SCLC seems to have the worst long-term prognosis of all forms of lung cancer. Although data on c-SCLC is very sparse, some studies suggest that survival rates in c-SCLC may be even worse than that of pure SCLC, likely due to the lower rate of complete response to chemoradiation in c-SCLC, although not all studies have shown a significant difference in survival.

Untreated "pure" SCLC patients have a median survival time of between 4 weeks and 4 months, depending on stage and performance status at the time of diagnosis.

Given proper multimodality treatment, SCLC patients with limited disease have median survival rates of between 16 and 24 months, and about 20% will be cured. In patients with extensive disease SCLC, although 60% to 70% will have good-to-complete responses to treatment, very few will be cured, with a median survival of only 6 to 10 months.

Some evidence suggests that c-SCLC patients who continue to smoke may have much worse outcomes after treatment than those who quit.

a) Surgical resection is mainstay of treatment, whenever possible. If tumor is completely removed, post-operative radiation therapy is typically not needed since acinic cell is considered a low-grade histology. Post-operative radiation therapy for acinic cell carcinoma is used if: 1) margins are positive, 2) incomplete resection, 3) tumor invades beyond gland, 4) positive lymph nodes.

b) Neutron beam radiation

c) Conventional radiation

d) Chemotherapy

This form of cancer is often seen in those who chew tobacco or use snuff orally, so much so that it is sometimes referred to as "Snuff dipper's cancer." Chewing betel nuts is an additional risk factor commonly seen in Taiwan.

Salivary gland–like carcinomas of the lung generally refers a class of rare cancers that arise from the uncontrolled cell division (mitosis) of mutated cancer stem cells in lung tissue. They take their name partly from the appearance of their abnormal cells, whose structure and features closely resemble those of cancers that form in the major salivary glands (parotid glands, submandibular glands and sublingual glands) of the head and neck. Carcinoma is a term for malignant neoplasms derived from cells of epithelial lineage, and/or that exhibit cytological or tissue architectural features characteristically found in epithelial cells.

This class of primary lung cancers contains several histological variants, including mucoepidermoid carcinoma of the lung, adenoid cystic carcinoma of the lung, epithelial-myoepithelial carcinoma of the lung, and other (even more rare) variants. .

Pulmonary neuroendocrine tumors are neuroendocrine tumors localized to the lung: bronchus or pulmonary parenchyma.

Pulmonary neuroendocrine tumors include a spectrum of tumors from the low-grade typical pulmonary carcinoid tumor and intermediate-grade atypical pulmonary carcinoid tumor to the high-grade pulmonary large cell neuroendocrine carcinoma (LCNEC) and pulmonary small cell carcinoma (SCLC), with significant clinical, epidemiologic and genetic differences.

Lung cancers have been historically classified using two major paradigms. Histological classification systems group lung cancers according to the appearance of the cells and surrounding tissues when they are viewed under a microscope. Clinical classification systems divide lung cancers into groups based on medical criteria, particularly their response to different treatment regimens.

Before the mid-1900s, lung cancer was considered to be a single disease entity, with all forms treated similarly. In the 1960s, small cell lung carcinoma (SCLC) was recognized as a unique form of lung cancer, based both on its appearance (histology) and its clinical properties, including much greater susceptibility to chemotherapy and radiation, more rapid growth rate, and its propensity to metastasize widely early on in its course. Since then, most oncologists have based patient treatment decisions on a dichotomous division of lung cancers into SCLC and non-small cell lung carcinomas (NSCLC), with the former being treated primarily with chemoradiation, and the latter with surgery.

An explosion of new knowledge, accumulated mainly over the last 20 years, has proved that lung cancers should be considered an extremely heterogeneous family of neoplasms with widely varying genetic, biological, and clinical characteristics, particularly their responsiveness to the large number of newer treatment protocols. Well over 50 different histological variants are now recognized under the 2004 revision of the World Health Organization ("WHO-2004") typing system, currently the most widely used lung cancer classification scheme. Recent studies have shown beyond doubt that the old clinical classification paradigm of "SCLC vs. NSCLC" is now obsolete, and that correct "subclassification" of lung cancer cases is necessary to assure that lung cancer patients receive optimum management.

Approximately 98% of lung cancers are carcinoma, which are tumors composed of cells with epithelial characteristics. LCLC's are one of 8 major groups of lung carcinomas recognized in WHO-2004:

- Squamous cell carcinoma

- Small cell carcinoma

- Adenocarcinoma

- Large cell carcinoma

- Adenosquamous carcinoma

- Sarcomatoid carcinoma

- Carcinoid tumor

- Salivary gland-like carcinoma

Squamous-cell carcinoma (SCC) of the lung is a type of non-small-cell lung carcinoma and is more common in men than in women. It is closely correlated with a history of tobacco smoking, more so than most other types of lung cancer. According to the Nurses' Health Study, the relative risk of SCC is approximately 5.5, both among those with a previous duration of smoking of 1 to 20 years, and those with 20 to 30 years, compared to never-smokers. The relative risk increases to approximately 16 with a previous smoking duration of 30 to 40 years, and approximately 22 with more than 40 years.

Clear-cell adenocarcinoma is a type of adenocarcinoma that shows clear cells.

Types include:

- Clear-cell adenocarcinoma of the vagina

- Clear-cell ovarian carcinoma

- Uterine clear-cell carcinoma

- Clear-cell adenocarcinoma of the lung (which is a type of Clear-cell carcinoma of the lung)

See also:

- Clear-cell squamous cell carcinoma of the lung